taxonID	type	description	language	source
03DBF911FFE6FFA8FEFCFB944BC4FBD6.taxon	materials_examined	Type locality: VENEZUELA; Nueva Esparta State; Margarita Island; La Restinga lagoon, 64 02 ' – 64 12 ' W 10 90 ' – 11 02 ' N (P. Penchaszadeh col.). Description: Shell (Figs. 10 – 12): Wide, somewhat flat, concave, outline oval; walls thin, transparent. Color cream, with pale brown, narrow, irregular spiral, radial bands. Periostracum absent, except very narrow portions in shell edges. Outer surface with weak growth lines. Anterior edge of septum with broad and shallow central notch, with edges almost straight, and another shallow notch in left end, narrower (Fig. 11). Inner surface glossy. Head­foot (Figs. 36, 42): Head differentiated, preceded by long, dorso­ventrally flattened, neck region, about half as long as foot. Proboscis short, cylindrical, can be entirely retracted within haemocoelic cavity (Fig. 36). Tentacles long, stubby, apex somewhat bifid. Eyes dark, small, located on very short ommatophores in basal region of tentacles lateral margin. Neck with pair of lateral, flattened lappets (nuchal lobes); left expansion narrower than right one; right expansion bringing low food groove along its dorsal­medial limit (Fig. 36: fg). Foot wide (occupies about 3 / 4 of shell ventral area, dorso­ventrally greatly flattened, thin; distinct longitudinal inner sinus runs in median line; shell septum as dorsal foot limit. Mantle fuses with dorsal surface of foot and protrudes beyond its borders. Furrow of pedal glands transverse, in anterior margin of foot; this anterior margin of foot covered dorsally by posterior region of neck ventral surface. Columellar muscle reduced, very small, contours anterior border of shell septum, more pronounced on right (Fig. 36: cm) in smaller specimens and almost absent in larger ones. Inner haemocoel cavity narrow, running approximately in center of neck region. Inner space almost all filled by great quantity of transverse, very slender muscular fibers; these fibers connect ventral surface of dorsal haemocoel wall with dorsal surface of its ventral wall, contouring salivary glands and esophagus (Fig. 42: tm). No vestiges of operculum even in very young specimens (smaller than 1 mm) inside egg capsules. Mantle organs (Figs. 35, 37 – 40): Mantle border thick, slightly hollow due broad collar sinuses (Fig. 40). Mantle border surrounds entire ventral margin of shell, free in anterior third and attached to foot margins in posterior 2 / 3, situated slightly away from foots edge, connected to it by a thin, semi­transparent portion. Mantle border without appendages, but filled entirely by series of minute repugnatorial glands, aligned inside mantle edge. Mantle border with special arrangement of folds in middle region of opening of pallial cavity, broad fold starting at anterior end of gill, running towards left, decreasing in width, disappearing abruptly at level of osphradium; its broader region possesses a central, broad furrow, its posterior edge expands beyond mantle border covering ventrally anterior region of gill, its anterior edge slightly projected outside (Fig. 37). Dorsal shell muscle well developed (Fig. 35: dm), origin small, in about middle­right region of shell, just anterior to septum; their fibers run fan­like anteriorly, insertion in adjacent anterior region of dorsal surface of pallial cavity. Lateral shell muscle (Figs. 35: lm) very small, fan­like, located close to mantle border on right side, just in region where pallial cavity penetrates shell septum chamber. Opening of pallial cavity occupies about 2 / 3 of anterior half of shell margin turned to right (if shell compared with a clock, in dorsal view and with head occupying 12 oclock, pallial aperture begins in 10 and finishes in 2 oclock) (Fig. 38). Pallial cavity deep, broad, triangular, arched and dorso­ventrally flattened. Anterior extremity of pallial cavity slightly larger than its opening due to closure in left and right extremities produced by fusion of mantle and foot (Figs. 38, 39: ml). Gradually, pallial cavity narrows towards posterior, extending at left of visceral mass (described below); cavity length about 2 / 3 of total length of animal (Figs. 35, 38, 39). Osphradium very small, monopectinate, located between anterior half of gill and mantle border, at some distance from gill anterior end, located about in left region of pallial aperture somewhat perpendicular to longitudinal axis of animal body (Figs. 38). Length of osphradium slightly more than 1 / 6 of length of pallial opening, shaped like a small fold, attached to mantle, separated from gill structures. Osphradium leaflets cylindrical, separated from each other, somewhat thick and tall, approximately 9 in number (Fig. 37). Osphradial ganglion narrow. Gill very large, its base somewhat narrow, surrounding anterior and left margin of pallial cavity [almost entire length of this cavity; anterior tip of gill in rightanterior region of opening of pallial cavity, close to its right limit, on thick mantle border; posterior margin of gill in posterior end of pallial cavity (Fig. 39). Basal region of gill filaments triangular, with very long, almost straight, narrow, stiff rod turned to right (Fig. 40); rods about three times as long as their triangular, membranous base; rods begin in ctenidial vein region, in left margin of cavity roof, touching food groove of head­foot, in right margin of cavity floor; rod apex rounded and preceded by thicker region. Gill filaments stay connected with each other by cilia, mainly of their thicker apical region, maintaining them in somewhat firm position. Gill filaments longer in central gill region, shortening gradually in both extremities; anterior tip of gill, with short filaments, suddenly turning forwards, located on mantle border (Figs. 37 – 39). Ctenidial vein narrow, of uniform width along its length. Endostyle well­developed (Figs. 37, 39: en), yellowish, in form of broad and flat glandular ridge located in middle level of ventral surface of ctenidial vein all along its length. Hypobranchial gland whitish, thin, weakly developed, surface smooth; occupies area between gill and visceral mass. About 1 / 3 of visceral mass encroaching on pallial cavity roof (Fig. 39), occupying about 1 / 3 of this cavity in posterior­right region; pericardium and kidney posteriorly; intestinal loop long, anus and pallial oviduct anteriorly (described below). Visceral mass (Figs. 35, 38, 39): Dorso­ventrally flattened, cone­shaped, housed in shell chamber produced by thin calcareous septum (Fig. 35); separating visceral mass from dorsal surface of foot. Left and anterior region of visceral mass occupied by pallial cavity (Figs. 35, 39). Remaining regions of visceral mass with stomach as central structure, immediately surrounded by digestive gland (except in some ventral and dorsal areas). Gonad surrounds externally digestive gland, more concentrated anteriorly. All structures described in more details below. Visceral mass also lies on right­posterior region of pallial cavity roof as described above, and possesses another ventral flap forming floor of pallial cavity. Anterior extremity of visceral mass ventral flap stays just in shell septum anterior border, covering columellar muscle (Figs. 38, 39). Circulatory and excretory systems (Figs. 39, 41): Pericardium somewhat triangular and broad, situated obliquely to longitudinal axis of animal (Fig. 35: pc). Left region of pericardium very narrow, forming a vein connecting gill with auricle, beginning just at posterior end of gill, in posterior­left end of pallial cavity; running along anterior margin of visceral mass (its portion in pallial roof), about in middle level of this region of visceral mass it connects to auricle, near median line. Remaining pericardium limits: 1) anterior and ventral pallial cavity; 2) posterior visceral mass (gonad generally); 3) dorsal mantle; 4) right kidney. Auricle thin­walled, long, narrow, runs all along broader region of pericardium, attached to its anterior and dorsal inner surfaces (Fig. 41); connecting with ventricle approximately in its middle portion; auricle having broad portion beyond ventricle connection as blind sac (Fig. 41: ab), bearing orifice to nephridial gland. Ventricle elliptical, very muscular; its connection with auricle located about in middle region of its anterior surface; on opposite side bears origin of aortas. Anterior aorta broad, running towards opposite side than posterior aorta. Anterior aorta running towards right, adjacent to posterior inner pericardium surface; penetrating head haemocoel. Kidney occupying about half of visceral mass within pallial cavity (Figs. 39, 41). Kidney limits: 1) dorsal mantle; 2) ventral pallial cavity; 3) posterior­right visceral mass (gonad generally); 4) posterior­left pericardium; 5) anterior an intestinal loop; 6) lateral­right intestine and oviduct (when present). Kidney central region hollow, with single lobe (Fig. 41). Kidney lobe slightly uniform, covers dorsal surface, intestinal region passing through kidney chamber, and about 1 / 4 of inner space of kidney adjacent to intestine. Nephridial gland in renal limit with pericardium, very small, presenting a series of triangular, transversal, narrow folds connected with dorsal renal lobe (Fig. 41: ng). Nephrostome a very small slit in left­anterior region of ventral wall (Figs. 39, 41), in anterior region of hollow portion of kidney; no inner glandular folds close to it. Adrectal sinus very broad, adjacent to externally intestine loop exposed in pallial cavity, connected to main kidney chamber by a narrow region presenting a branch of renal lobe; this branch runs a short distance inside adrectal sinus (Fig. 41). Digestive system (Figs. 42 – 49, 51): Proboscis short and broad, with capacity of retraction inside haemocoel in small rhynchocoel (Figs. 36, 42), but a short snout remains. Pair of narrow ventral proboscis retractor muscles very thin, immersed in proboscis wall. Mouth longitudinal, in center of anterior proboscis surface. Buccal mass very large, occupying most of proboscis inner space and short portion of haemocoel posterior to it. Jaw plates in dorsal wall of buccal mass, thin, almost vestigial, broad laterally, short longitudinally (Fig. 44). Pair of dorsal folds broad and tall, begin at some distance posterior to jaws; dorsal chamber between both folds shallow. Odontophore occupying about 1 / 4 of haemocoelic space, and most of buccal mass volume. Odontophore muscles (Figs. 43, 45 – 49: m 1) jugal muscles, several very narrow muscles connecting buccal mass with adjacent wall of snout, more concentrated anteriorly around mouth; m 1 a) pair of dorsal protractor muscles, narrow, thin and superficial, origin in anterior­dorsal region of mouth, close to median line, inserting in posterior­dorsal­lateral region of odontophore; m 2) pair of retractor muscle of buccal mass (retractor of pharynx), broad, origin in lateralventral region of haemocoel just posterior to snout, run towards anterior, insertion in lateral­posterior­dorsal region of odontophore cartilages; m 2 a) pair of dorsal tensor muscles of radula, continuation of m 2 after insertion in cartilages, run towards anterior, insertion in subradular cartilage in middle region of its dorsal inner surface; mt) dorsal transversal muscle or approximator muscle of cartilages, connects dorsally both posteriordorsal­lateral surfaces of cartilages, lies between superficial membrane which covers odontophore and tissue on middle region of radula (to); m 4) pair of median dorsal tensor muscle of radula, very large and thick, origin in ventral­middle­posterior region of odontophore cartilages, run towards medial, contours medial­ventral surface of cartilages, run on their dorsal surface, insertion in subradular cartilage dorsal­posterior­medial extremities; m 5) pair of median radular tensor muscle, thick, origin in median­posteriordorsal region of odontophore cartilages, just by side of m 2 insertion and m 2 a origin, cover perpendicularly m 4 middle region, run towards medial, insertion along radular sac in its both sides (each m 5 branch covers a side of radular sac, medially and dorsally); m 6) horizontal muscle, very thin, unites anterior half of odontophore cartilages, inserting on their dorsal margin; m 7) pair of ventral tensor muscle of radula, thin and narrow, origin inside radular sac ventral surface close to each other, run towards anterior separating gradually from each other, insertion in radula ventral border; m 8) pair of strong muscles origin in posterior­dorsal­lateral regions of odontophore cartilages just by side of insertion of m 2, run attached to dorsal margin of odontophore cartilages, insert in their anteriordorsal region close to horizontal muscle (m 6); m 9) pair of dorsal­medial tensor muscle of radula, broad and thin, origin along dorsal­median surface of radular sac (in its region internal to odontophore), cross to dorsal surface, insert in dorsal­ventral border of subradular cartilage; mj) jaws and peribuccal muscles, of moderate thickness, surround lateral and dorsal wall of buccal mass, origin around mouth, insertion in middle level of lateral and dorsal wall of odontophore; m 11) absent; m 14) pair broad and thin, origin in posterior­dorsal region of odontophore, close to m 2 and m 5 origins, runs towards ventral and anterior, insertion in snout inner ventral surface in about middle level of odontophore; to) tissue covering middle region of radula within odontophore, in its dorsal surface. Radula short, little longer than odontophore. Radula (Figs. 26, 27): rachidian tooth tall, narrow, strongly curved inwards, central cusp large and sharp, 3 to 4 similar sized pairs of secondary cusps, pair of lateral reinforcements on its borders somewhat weak; lateral tooth about 3 times as broad as rachidian, curved internally, with about 12 triangular cusps, fifth cusp larger, apical, turned towards median, cusps decrease towards lateral, disappear about in middle region of tooth, remaining a slight thick and arched border; inner marginal tooth long, curved, tall, tip sharp pointed, about 9 sub­terminal cusps along its inner­apical margin and up to 6 very small cusps along outer margin; outer marginal tooth similar to inner marginal tooth, except in being slender, and with 2 – 3 small cusps along its inner margin only. Pair of buccal ganglia large, close with each other near median line (Fig. 43), located between buccal mass and adjacent esophagus. Salivary glands narrow, slender, long; length about half of that of haemocoel (Figs. 42). Salivary glands do not pass through nerve ring. Ducts of salivary glands broad, run in dorsal surface of buccal mass, penetrate in adjacent buccal mass wall a short distance, openings small in anterior region of dorsal folds of buccal mass (Figs. 44). Esophagus (Figs. 42, 43, 51) narrow, long and somewhat coiled; inner surface of anterior esophagus with pair of broad folds. Stomach (Fig. 51) slightly conical, large, occupying about half of visceral mass size; esophagus inserting in left side of its posterior­left region, close to shell apex. Anterior duct to digestive gland about in middle region of stomach ventral surface; highly branched. Posterior duct to digestive gland very narrow, located in ventral region of stomach posterior end, turned posteriorly. Stomach gradually narrowing towards anterior and left, arriving close to left­posterior extremity of pallial cavity. Stomach inner surface with pair of longitudinal folds, posterior to esophagus insertion, separating intestine from style sac region of stomach. Digestive gland pale brown in color, surrounding stomach except some areas in dorsal and ventral surfaces. Intestine narrow and sinuous (Fig. 51); running along anterior border of visceral mass from left to right, initially in its ventral region, slightly near median line cross to its dorsal region and runs up to right­anterior extremity of visceral mass (Fig. 51); running towards left in this region, becoming broader and exposed in pallial cavity, surrounds right and anterior border of kidney, suddenly runs towards right in a U­shape, parallel to preceding loop. Anus small, siphoned, located in right region of pallial cavity close to mantle border. Intestine last loops replete of several somewhat small, elliptical fecal pellets. Genital system: Development: Protandric hermaphrodite, further details in Miloslavich & Penchaszadeh (2001). No male examined herein. Female (Fig. 50): Ovary yellow, surrounds digestive gland, more concentrated in anterior region of visceral mass (Fig. 38). Visceral oviduct formed by gradual decrease from right­anterior end of ovary. Gonopericardial duct narrow; origin in right­ventral extremity of pericardium, running ventral to visceral glands encroached in pallial cavity, inserting in posterior extremity of pallial oviduct joined with insertion of visceral oviduct. Pallial oviduct relatively small, located in right­anterior end of pallial cavity (Figs. 35, 38). Visceral oviduct preceding pallial oviduct somewhat broad. A pair of seminal receptacles located in right side of last portion of visceral oviduct; each one as a small sac; duct very narrow and long; their insertion preceding albumen gland, in right surface. Albumen gland long, narrow, whitish, walls thick glandular; located in anterior­right extremity of visceral mass. Capsule gland as continuation of albumen gland, broad, spherical; walls thick glandular, pale brown; inner duct narrow, U­shaped. Genital pore in form of tall, long papilla close to mantle border and at right of anus. This papilla has a broader base and a somewhat conical form; a pair of low folds runs close to each other along its posterior side; both start gradually in papilla base and finish at some distance from pore; right fold slightly longer than left one. Habitat: Attached to the mangrove oyster Crassostrea rhizophorae (Guilding, 1828), that is attached to mangrove roots of Rhizophora mangle Linné, 1753, from 0.5 to 1.0 m depth.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFE6FFA8FEFCFB944BC4FBD6.taxon	distribution	Distribution: Venezuela.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFE6FFA8FEFCFB944BC4FBD6.taxon	description	Measurements of shells (in mm): MZSP 36329, ♀: 1: 17.8 by 12.0; ♀ 2: 16.3 by 10.6.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFE6FFA8FEFCFB944BC4FBD6.taxon	materials_examined	Material examined: types.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFE6FFA8FEFCFB944BC4FBD6.taxon	discussion	Discussion: Crepidula margarita was previously identified as C. aplysioides Reeve, 1859 in some previous papers (Hoagland, 1977; Simone et al. 2000; Miloslavich et al. 2001, 2003). However, further examination of the type specimens of C. aplysioides at BMNH revealed some important conchological differences. They share the external fashion, flat, wide, with terminal apex (Figs. 119 – 121). However, C. aplysioides type specimens (Figs. 119 – 122) possess a large muscle scar just dorsal to the right insertion of the septum (Figs. 119, 122 arrow). This feature is not found in the Crepidula plana complex, with normally has this muscle scar small and inconspicuous. Larger dorsal muscle scars are found in the western Atlantic species only in C. convexa (commented below) and Bostrycapulus aculeatus that I have examined. C. margarita additionally differs from C. aplysioides in having longitudinal colored bands, by apex closer to the posterior shell edge, and by loss of periostracum. The type locality of C. aplysioides is Rio de Janeiro. However, the imprecision of the South American localities in the middle of 19 th century is well known, and “ Rio de Janeiro ” can be any city located in Atlantic coast of that mainland. Hoagland (1977) had commented on the systematic problems related to C. aplysioides, but she could not resolve them because of the absence of the types. Anyway, based on the description, the examined species of that paper appears to be of C. margarita. C. aplysioides has the shell apex somewhat projected posteriorly and slightly away from the shell base, which approaches it from C. convexa (see below). On the other hand, C. aplysioides has a well developed beige periostracum, that show some similarity with C. carioca and C. pyguaia described below.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFECFFB4FEFCFB44489BFD16.taxon	description	Synonymy part in Hoagland (1977: 389). Complement:	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFECFFB4FEFCFB44489BFD16.taxon	materials_examined	Type: Neotype ANSP 19186 (designed by Collin [2000]); UNITED STATES OF AMERICA, Massachusetts, Woods Hole, 41 º 30 ' N 70 º 40 ' W.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFECFFB4FEFCFB44489BFD16.taxon	diagnosis	Differential Diagnosis: Shell (Figs. 1, 2): Wide and flat, convex or concave, outline oval. Color white. Outer surface smooth except for weak growth lines. Septum deep and bulged ventrally; anterior edge with a broad median notch and others in each side, just in insertion in the remaining shell. Other details in Collin (2000). Head­foot (Figs. 53, 58, 63): Tip of tentacles simple. Eyes dark, small, located on very small ommatophores between basal and middle third of tentacles lateral margin. Left neck lappet (nuchal lobe) broader than right one; right lappet brings low food groove along its dorsal limit with head; sperm groove of males (described below) running externally along food groove (Fig. 63). Foot occupying about 3 / 4 of shell concavity. Columellar muscle very small, contouring anterior border of shell septum, more concentrated at right (Figs. 53, 63) in smaller specimens and almost absent in larger ones. Mantle organs (Figs. 52, 54 – 57): Mantle border thick, slight hollow due broad collar sinuses (Fig. 56). Mantle border without appendages, but entirely surrounded by series of minute repugnatorial glands; these glands arranged in elliptical form. Mantle border with special arrangement of folds in middle region of pallial cavity opening, a broad fold located from gill anterior end running towards left, decreasing and disappearing suddenly at level of osphradium; its broader region possessing a central furrow, its posterior edge expanding beyond mantle border covering ventrally anterior region of gill, its anterior edge slightly projecting outside (Fig. 57); a central, low fold, beginning in median region of above described fold, appearing gradually, becoming gradually weak at level of osphradium, producing a narrow furrow with posterior edge of main fold. Dorsal shell muscle well developed (Fig. 52: dm), origin small, in about middle­right region of shell, just anterior to septum; its fibers run anteriorly like a fan, insertion in adjacent anterior region of dorsal surface of pallial cavity. Lateral shell muscle (Fig. 52: lm) very small, fanlike, located close to mantle border right side, just in region where pallial cavity penetrates shell septum chamber. Pallial cavity aperture occupies about 2 / 3 of anterior half of shell border turned to right (if shell compared with a clock, in dorsal view and with head occupying 12 oclock, pallial aperture begins in 10 and finishes in 2 oclock) (Fig. 54). Pallial cavity length about 2 / 3 of total length of animal (Figs. 52, 55). Osphradium very small, monopectinate, located between anterior half of gill and mantle border, at some distance from gill anterior end, located about in left region of pallial aperture somewhat perpendicular to longitudinal axis of animal body (Figs. 54, 55, 57). Osphradium length little more than 1 / 10 of pallial aperture length, in form of a small fold, attached to mantle, separated from gill structures. Osphradium leaflets rounded, close to each other, somewhat thick and tall, varying around 8 in number (Fig. 57). Osphradium ganglion narrow. Gill filaments triangular in their base and with very long, almost straight, narrow, stiff rod turned to right (Fig. 56); rods extend about three times longer than their triangular, membranous base; these rods begin in ctenidial vein region, in left margin of cavity roof and touches food groove of head­foot, in right margin of cavity floor; rod apex rounded and preceded by thicker region. Ctenidial vein narrow, with uniform width along its length. Endostyle (Figs. 55, 57: en) yellowish, in form of somewhat narrow glandular ridge located in middle level of ventral surface of ctenidial vein all along its length. Endostyle divided along its length by a narrow, middle furrow, into 2 similar ridges (Fig. 57). Hypobranchial gland whitish, thin, weakly developed, surface smooth; occupies area between gill and visceral mass. About 1 / 3 of visceral mass encroaches in pallial cavity roof (Fig. 55), occupying about 1 / 3 of this area in posterior­right region; pericardium and kidney posteriorly; a long intestinal loop, anus and pallial oviduct anteriorly (described below). Visceral mass (Figs. 52, 54, 55): Morphological attributes similar to those of C. margarita, proportionally longer only. Circulatory and excretory systems (Fig. 59): Pericardium very long, situated oblique to longitudinal axis of animal (Fig. 52); begins very narrow, just in posterior extremity of gill, in posterior­left end of pallial cavity; runs edging anterior margin of visceral mass part encroached in pallial roof, gradually enlarges; finishes in about middle level of this region of visceral mass, near median line. Auricle thin walled and very long, runs all along pericardium length attached to its anterior and dorsal inner surfaces (Fig. 59); connecting with ventricle approximately between its middle and right third parts; auricle has, then, broad portion beyond ventricle connection (Fig. 59: ab). Kidney occupying about half of area of visceral mass within pallial cavity (Figs. 55, 59). Kidney central region hollow, with single, irregular lobe (Fig. 59). Kidney lobe rich in transversal, folds not uniform in size, covering entire intestinal region passing through kidney chamber, and about half of inner space of kidney adjacent to intestine. Nephridial gland in renal limit with pericardium, very small, presenting a series of triangular, transversal, narrow folds connected with dorsal renal lobe. Nephrostome a very small slit in left region of ventral wall (Fig. 59), in middle region of hollow portion of kidney; no inner glandular folds close to it. Adrectal sinus narrow, edging externally intestine loop exposed in pallial cavity, becoming slightly broader towards posterior; connecting directly to kidney chamber anterior­left edge. Digestive system (Figs. 60 – 62): Buccal mass very large, occupying most of proboscis inner space and about 1 / 3 of haemocoel posterior to it. Jaw plates thinner. Pair of dorsal folds broad and tall. Odontophore muscles (Figs. 60, 61): mj) jaws and peribuccal muscles, somewhat thick, surround lateral and dorsal wall of buccal mass, origin around mouth, insertion in middle level of lateral and dorsal wall of odontophore; m 10) pair of ventral protractor muscles of odontophore, forming median edge of mj and fused with these; m 14) pair narrow and thin. Radula short, little more than odontophore length. Radula (Fig. 28, 29): rachidian tooth secondary cusps vary from 3 to 6 pairs, considerably smaller than central cusp; lateral tooth with about 12 triangular cusps, fifth cusp very larger; inner marginal tooth with about 8 cusps in its inner­subapical margin and 4 – 6 in its outer­subapical margin; outer marginal tooth with about 4 small cusps in inner margin. Salivary glands long, slender, coiled (Fig. 58), with about 2 / 3 of haemocoel length, do not pass through nerve ring. Ducts of salivary glands broad, running in dorsal surface of buccal mass, penetrating in adjacent buccal mass wall in short distance, apertures small in middle region of dorsal folds of buccal mass. Esophagus (Figs. 54, 58, 62, 65) narrow, long and coiled; anterior esophagus inner surface with pair of broad folds as continuation of those of buccal mass dorsal wall, located in opposite side from each other. Middle and posterior esophagus inner surface with only 4 – 5 longitudinal, narrow, similar sized folds. Stomach (Figs. 62, 65) somewhat slender. Anterior duct to digestive gland about in middle region of stomach ventral surface; highly dichotomic. Stomach gradually narrowing towards anterior and left, arriving close to left­posterior extremity of pallial cavity. Posterior duct narrow, strongly turned posteriorly. Stomach inner surface (Fig. 62) with square gastric shield located in right­posterior region, opposite to esophageal insertion; a narrow fold starts in right side of esophageal insertion and runs towards anterior, surrounding left and anterior edges of gastric shield; another fold, transversal, somewhat tall, located just anterior to posterior duct to digestive gland; this fold suddenly runs towards anterior in left gastric surface originating a pair of longitudinal folds dividing gastric surface into intestinal and style sac portions. No preserved crystalline style found. Digestive gland greenish brown in color, surrounding stomach except some areas in dorsal and ventral surfaces (Figs. 52, 65). Intestine narrow and sinuous (Fig. 62) differing by ampler middle loop, approaching first free portion of intestine from style sac, and renal portion from rectum. Anus small, siphoned, located in right region of pallial cavity close to mantle border. Genital system. Development: See Collin (2000). Male (Figs. 63 – 65, 67): Larger examined male with 9.7 mm. Testis pale yellow in color, located in anterior region of visceral mass (Fig. 65). Seminal vesicle convoluted, thick, broad, cream in color, located in anterior­right extremity of visceral mass, gradually narrows and becomes very slender tube that opens in right­posterior­ventral region of pallial cavity (Figs. 64, 65); in this portion, passing close to vestigial pallial oviduct. Shallow groove running from this aperture up to penis base, in pallial floor near right margin of head. Sperm groove more clear and deep anteriorly. Penis large (several times tentacle length and width), curved; suddenly narrows before tip producing a very long papilla (Figs. 63, 67), with about half of penis length and about 1 / 10 of its width. Penis duct opened (groove), running about in middle region of penis ventral surface until papilla tip. A small, somewhat spherical, incipient oviduct found in some males (Figs. 64, 65: vt), in region preceding aperture of visceral vas deferens in pallial cavity. Female (Fig. 66): Ovary yellow, surrounding digestive gland, more concentrated in anterior region of visceral mass (Fig. 54). Visceral oviduct very narrow, running from left to right in anterior border of visceral mass. Gonopericardial duct well­developed, weakly broader than visceral oviduct; originating in right­ventral extremity of pericardium, running ventral to visceral glands encroached in pallial cavity, inserting in posterior extremity of pallial oviduct joined with insertion of visceral oviduct. Pallial oviduct relatively small, located in right­anterior end of pallial cavity (Figs. 52, 55). Albumen gland long, slight broad, whitish, walls thick glandular; located in anterior­right extremity of visceral mass. About 5 seminal receptacles inserted in right side of albumen gland, successively larger towards anterior. Seminal receptacles duct broad and very short. Capsule gland broad, thick, occupying about half of pallial oviduct volume; walls thick glandular; inner duct narrow, flat, straight. Vaginal tube originating from anterior­left corner of capsule gland; running towards left, after a short distance suddenly twist and runs towards right, parallel to capsule gland; form somewhat thick and broad (about ¼ of capsule gland width); length about same of that of capsule gland. Genital papilla very tall, situated close to anterior region of albumen gland, at some distance from anus. Papilla with a pair of longitudinal folds along posterior surface; left fold longer, starts gradually in papilla base, and finishes in a conspicuous fold situated parallel to pore; right folds short, starts as a low fold of middle region of papilla, finishes in posterior edge of pore. Genital pore a small, transversal, terminal slit. Habitat: See Collin (2000), subtidal, in shells occupied by hermit crabs.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFECFFB4FEFCFB44489BFD16.taxon	distribution	Distribution: East coast of North America, from New Brunswick (Canada) to Georgia (USA).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFECFFB4FEFCFB44489BFD16.taxon	description	Measurements of shells (in mm) MZSP 36327 ♀ 1: 19.4 by 12.2; ♀ 2: 16.5 by 9.5; ♀ 3: 8.4 by 6.0 (immature); ♀ 4: 17.0 by 13.5; ♂ 5: 8.7 by 6.8; ♀ 6: 8.8 by 6.3 (mature); ♂ 7: 9.7 by 6.0; ♂ 8: 6.1 by 6.3; ♂ 9: 9.0 by 7.3.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFECFFB4FEFCFB44489BFD16.taxon	materials_examined	Material examined: UNITED STATES OF AMERICA; Georgia; Saint Catherines Island, MZSP 36327, 4 ♀, 5 ♀ (R. Collin col.). South Carolina, ANSP 19495. 3 shells (Mrs. Say col.)	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF0FFB6FEFCFC844BE3FA46.taxon	materials_examined	Type: Holotype ANSP 19188; UNITED STATES OF AMERICA; Florida, Sanibel Island, Wolfert Point, 26 º 29 ' N 82 º 10 ' W. Paratypes FMNH 282203, 282206, 282217.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF0FFB6FEFCFC844BE3FA46.taxon	diagnosis	Differential diagnosis: Shell (Figs. 3, 4): growth lines stronger, producing a rougher outer surface. Other details in Collin (2000). Head­foot (Figs. 69, 75, 79): Color darker, with grey or black spots in foot sole and neck ventral surface. Tentacles tip weakly bifid. Eyes dark, very small, located on very short ommatophores in level between basal and middle thirds of tentacles lateral margin. Head and neck little shorter than foot length. Columellar muscle reduced, contours anterior border of shell septum, more concentrated at right (Fig. 69, 79), as in smaller specimens as in larger ones. Mantle organs (Figs. 68, 71 – 73): Mantle border special arrangement of folds in middle region of pallial cavity aperture with main fold narrower, located from gill anterior end running towards left, decreasing and disappearing gradually; anterior edge of this fold short, disappearing at short distance from gill anterior end; posterior edge continuing with inner edge of mantle border (Fig. 73). This broader fold with a weak central furrow. Dorsal shell muscle well developed (Fig. 68: dm), although thin. Lateral shell muscle (Figs. 68: lm) very small, located slightly posteriorly. Pallial cavity aperture occupies about 2 / 3 of anterior half of shell border turned to right (if shell compared with a clock, in dorsal view and with head occupying 12 oclock, pallial aperture begins in 9: 30 and finishes in 2: 30 oclock) (Fig. 70). Pallial cavity length about 4 / 5 of total length of animal (Figs. 68, 71). Osphradium very small, monopectinate, located between anterior half of gill and mantle border, at some distance from gill anterior end (Figs. 71, 73). Osphradium length about 1 / 10 of pallial aperture length, in form of a small fold, attached to mantle, separated from gill structures. Osphradium leaflets rounded, close to each other, somewhat thick and tall, varying around 7 in number (Fig. 73). Gill filaments triangular base somewhat longer, extending by about half of filament length (Fig. 72). Endostyle (Figs. 71, 73: en) yellowish, divided along its length by a narrow, middle furrow, into 2 similar ridges. Hypobranchial gland very thin, almost absent. Visceral mass (Figs. 68, 70, 80): broader and longer area of pallial cavity. Circulatory and excretory systems (Figs. 74, 77): Kidney central region mostly hollow, with single, irregular lobe, rich in longitudinal vessels (Fig. 77). A very broad vessel running in center, coming from adrectal sinus; a ventral branch coming from haemocoel; also several other smaller vessel branches covering dorsal, anterior and left surface of renal chamber, and local portion of intestine. Nephridial gland in renal limit with pericardium, very small, presenting a series of triangular, transversal, narrow folds connected with dorsal renal lobe (Fig. 77: ng) in anterior region, and longitudinal folds in posterior region. Nephrostome a very small slit in left region of ventral wall (Fig. 74), in middle region of hollow portion of kidney, protected at left by larger longitudinal vessel. Adrectal sinus broad, edging externally intestine loop exposed in pallial cavity almost all along its length; connecting directly to kidney chamber anterior­left edge. Digestive system (Figs. 76, 78): Buccal mass occupying most of proboscis inner space and a short portion of haemocoel posterior to it. Pair of dorsal folds broad, their inner edge closer to median line. Odontophore muscles (Fig. 76): m 11) pair of ventral tensor muscles of radula, originating in haemocoel ventral surface in region of proboscis base, running towards anterior, penetrating in odontophore ventral, middle region; inserting in subradular membrane in ventral end of radula. Radula extending little beyond odontophore length. Radula (Figs. 30, 31) similar to that of C. margarita, distinction and notes: rachidian tooth secondary cusps varying from 4 to 6 pairs; lateral tooth with about 14 – 16 triangular cusps, fifth cusp very larger; inner marginal tooth with 6 – 10 cusps along its inner­subapical margin and about 4 in outer subapical margin; inner marginal tooth with about 4 very small cusps along its inner subapical margin. Salivary glands very narrow and small (Fig. 75), with about 1 / 6 of haemocoel length. Salivary glands aperture a transversal slit in anterior region of dorsal folds of buccal mass. Esophagus (Figs. 75, 78, 80) narrow, long; anterior esophagus inner surface with pair of broad folds as continuation of those of buccal mass dorsal wall, located in opposite side from each other. Stomach (Fig. 78) somewhat more curved. Anterior duct to digestive gland about in middle region of stomach ventral surface; highly dichotomic. Stomach gradually narrowing towards anterior and left, arriving close to left­posterior extremity of pallial cavity. Posterior duct narrow, strongly turned towards posterior. Stomach inner surface (Fig. 78) with a very small gastric shield located in middle­right region of right surface of stomach, by side of esophageal insertion; a narrow fold starting in right side of posterior duct to digestive gland insertion, running towards anterior, along gastric ventral surface; bifurcating in a Y­ shape in region just anterior, and right of posterior duct to digestive gland, raising a transversal fold separating gastric chamber from style sac chamber; on opposite side, this transversal fold suddenly runs towards anterior in left gastric surface, originating a pair of longitudinal folds dividing gastric surface into intestinal and style sac portions. No preserved crystalline style found. Digestive gland pale beige in color. Intestine narrow (Fig. 78) differing by ampler and more separated loops. Anus small, siphoned, located in right region of pallial cavity close to mantle border. Genital system: Development: See Collin (2000). Male (Figs. 79 – 81): Largest male examined was 6.6 mm. Testis white in color, located in anterior and left regions of visceral mass. Seminal vesicle convoluted, narrow, cream in color, located in anterior­right extremity of visceral mass (Fig. 80). Penis large (about 4 times tentacle length, and about double width), curved; suddenly narrows before tip producing a very long papilla, with about 1 / 3 of penis length, papilla base somewhat broad, narrowing gradually towards distal (Figs. 79, 81). Penis furrow runs about in middle region of penis ventral surface until papilla tip. Female (Fig. 82): Ovary cream in color. Albumen gland narrower. About 5 seminal receptacles inserted in right side of albumen gland, successively smaller towards anterior. Seminal receptacles duct broad and short. Capsule gland narrower, inner duct narrow, flat, straight. Vaginal tube originating from anterior­left corner of capsule gland; running parallel to capsule gland towards right; form somewhat thick and broad (about 1 / 2 of capsule gland width); length about same as that of capsule gland. Genital papilla very tall, situated close to anterior region of albumen gland, at some distance from anus. Papilla with a single longitudinal fold along posterior surface, starting gradually in papilla base, finishing surrounding pore. Genital pore a small, transversal, terminal slit. Habitat: See Collin (2000), on oyster shells near mangrove roots, up to 1 m depth.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF0FFB6FEFCFC844BE3FA46.taxon	distribution	Distribution: North Carolina, Gulf and Atlantic coast of Florida, Florida Keys.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF0FFB6FEFCFC844BE3FA46.taxon	description	Measurements of shells (in mm): MZSP 36328 ♀ 1: 15.2 by 11.7; ♂ 2: 4.9 by 4.6; ♀ 3: 15.0 by 11.8; ♂ 4: 6.5 by 3.4; ♀ 5: 6.6 by 5.4 (mature).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF0FFB6FEFCFC844BE3FA46.taxon	materials_examined	Material examined: UNITED STATES OF AMERICA; Florida; Harbor Branch, MZSP 36328, 2 ♂, 3 ♀ (R. Collin col.)	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF2FFB0FEFCF9C64BF3FA46.taxon	diagnosis	Differential diagnosis: Shell (Figs. 5, 6): growth lines stronger, producing a rougher outer surface. Color entirely white. Anterior edge of septum with a deeper notch in left side. Other details in Collin (2000). Head­foot (Figs. 84, 89, 91): Tentacles tip simple. Eyes dark, very small, located on very short ommatophores in level between basal and middle thirds of tentacles lateral margin. Head and neck with about same foot length. Columellar muscle reduced, contours anterior border of shell septum, more concentrated at right (Fig. 84). Anterior edge of foot, with pedal gland furrow, presenting projected edges in both sides. Mantle organs (Figs. 83, 85 – 88): Mantle border special arrangement of folds in middle region of pallial cavity aperture with very broad main fold, located from gill anterior end running towards left, decreasing gradually (Figs. 87, 88); both edges of this fold unite at level of osphradium by a short distance, and connect to mantle border. This fold possesses a broad and shallow central furrow. Dorsal shell muscle well developed (Fig. 83: dm), relatively large. Lateral shell muscle (Figs. 83: lm) very small, almost absent. Pallial cavity aperture occupies about 2 / 3 of anterior half of shell border turned to right (if shell compared with a clock, in dorsal view and with head occupying 12 oclock, pallial aperture begins in 9: 30 and finishes in 3 oclock) (Fig. 86). Pallial cavity length about same of total length of animal (Figs. 83, 87). Osphradium very small, length about 1 / 10 of pallial aperture length. Osphradium leaflets rounded, slightly far from each other, somewhat thick and tall, varying around 8 in number (Fig. 88). Gill filaments triangular base somewhat longer, extending by about half of filament length, but narrower than that of C. atrasolea. Endostyle (Figs. 87, 88: en) divided along its length by a narrow, middle furrow, into 2 similar ridges. Hypobranchial gland very thin. Visceral mass (Figs. 83, 93): relatively shorter. Circulatory and excretory systems (Figs. 87): renal lobe slightly thicker attached to intestine. Digestive system (Figs. 89, 90, 92): Buccal mass occupying most of proboscis inner space and a short portion of haemocoel posterior to it. Pair of dorsal folds somewhat notched (Fig. 90) and narrow. Odontophore muscles: m 7 pair with insertion inside radular sac strongly connected with each other; m 11 pair also present; m 14, very narrow, almost filiform. Radula extending little beyond odontophore length. Radula (Fig. 32): rachidian tooth with 3 – 4 secondary cusps; lateral tooth with about 12 triangular cusps, forth cusp very larger; inner marginal tooth with about 8 cusps along its inner­subapical margin and 4 in along its outer subapical margin; inner marginal tooth with about 3 small and pointed cusps long its inner subapical margin. Salivary glands very narrow (Figs. 89), length little longer that half of haemocoel length. Salivary glands aperture an oblique slit in anterior region of dorsal folds of buccal mass (Fig. 90). Esophagus (Figs. 89, 92) very narrow, long. Stomach (Fig. 92) very similar to that of C. atrasolea, except for anterior and posterior ducts to digestive gland dichotomic at their base, practically double. Digestive gland greenish beige in color. Intestine very similar in attributes to that of C. atrasolea (Fig. 92). Genital system: Development: See Collin (2000). Male (Figs. 91, 93): Testis cream in color, located in anterior and left regions of visceral mass. Seminal vesicle proportionally larger, highly convoluted, narrow, cream in color, located in anterior­right extremity of visceral mass. Penis large (about 5 times tentacle length, and about 3 times its width), curved; narrowing gradually towards tip, lacking a clear separation with terminal papilla. Penis furrow runs in middle region of penis ventral surface until papilla tip. Female (Figs. 95, 96): Ovary pale yellow in color. Albumen gland narrower. About 4 seminal receptacles inserted in right side of albumen gland, successively larger towards anterior. Seminal receptacles duct narrow and long. Capsule gland narrower, inner duct narrow, flat, straight. Vaginal tube originating from left region of capsule gland; running parallel to capsule gland towards right; form very thick and broad (little slender than capsule gland width); length about same as that of capsule gland; vaginal tube inner surface with 7 – 8 longitudinal, irregular folds, starting just in region after capsule gland. Genital papilla very tall, situated close to anterior region of albumen gland (part covering it), at some distance from anus; its inner surface with vaginal tube folds converging and becoming only 3 broad longitudinal folds. Papilla with about 5 longitudinal folds along posterior and left surfaces, starting gradually in papilla base, finishing at short distance from pore; those more posterior folds taller, forming a deep furrow between their distal end as genital pore lips. Genital pore a small, transversal, terminal slit. Central nervous system (Figs. 89, 94): With normal characters as in other described Crepidula (Simone 2002), located posterior, far removed from buccal mass, ganglia somewhat concentrated, statocyst with statolith. Habitat: See Collin (2000), on oyster shells and shells occupied by hermit crabs, 3 – 5 m depth.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF2FFB0FEFCF9C64BF3FA46.taxon	distribution	Distribution: Gulf coast of Texas, Gulf and Atlantic coasts of Florida.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF2FFB0FEFCF9C64BF3FA46.taxon	description	Measurements of shells (in mm): MZSP 36326 ♀ 1: 14.1 by 10.5; ♂ 2: 4.8 by 3.6; ♀ 3: 9.7 by 7.2.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF2FFB0FEFCF9C64BF3FA46.taxon	materials_examined	Material examined: UNITED STATES OF AMERICA; Florida; Sanibel Marina, MZSP 36326, 10 specimens (R. Collin col.); St. Petersberg, MZSP 35844, 16 specimens (T. Bert col. 1977, R. Collin leg & id.).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	description	Santo; off Vitória, MNRJ 8989, 5 shells (P. M. Costa col. otter trawl, 2001). RIO DE JANEIRO; Rio de Janeiro, Governador Island, Centro de Instrução da Marinha, MNRJ 2338, 1 ♀ (Adolfo Emigdio col. Iii / 1957). São Paulo; off Ubatuba (Integrated Project IOUSP, R. V. Veliger II col.), 23 ° 30 ' S 44 ° 54 ' W, 42 m depth, MZSP 30790, 5 specimens (Sta. 26, 21 / iv / 1986); 23 ° 25 ' S 44 ° 52 ' W, 21 m depth, MZSP 30803, 13 specimens (Sta. 27, 21 / iv / 1986); 23 ° 29 ' S 44 ° 52 ' W, 38 m depth, MZSP 30798, 2 specimens (Sta. 8, 28 / x / 1985); 23 ° 33 ' S 44 ° 50.5 ' W, 43 m depth, MZSP 30799, 2 ♀ (Sta. 7, 28 / x / 1985); 23 ° 34 ' S 44 ° 48 ' W, 44 m depth, MZSP 30801, 4 specimens (Sta. 17, 22 / i / 1986); 23 ° 34 ' S 45 ° 06 ' W, 21 m depth, MZSP 30802, 24 specimens (Sta. 12, 20 / i / 1986), 20 m depth, MZSP 30800, 1 specimen (Sta. 39, 21 / x / 1986); 23 ° 34 ' S 45 ° 07 ' W, 20 m depth, MZSP 30797, 2 specimens (Sta. 21, 18 / iv / 1986); 23 ° 38 ' S 44 ° 49 ' W, 47 m depth, MZSP 30795, 1 ♀ (Sta. 16, 22 / i / 1986); 23 ° 38 ' S 45 ° 14 ' W, 16 m depth, MZSP 30805, 1 specimen (Sta. 42, 22 / x / 1986); 23 ° 39 ' S 45 ° 04 ' W, 36 m depth, MZSP 30792, 2 ♂ (Sta. 11, 20 / i / 1986); 23 ° 44 ' S 45 ° 00 ' W, 42 m depth, MZSP 30796, 2 ♀ (Sta. 37, 21 / x / 1986); 23 ° 44 ' S 45 ° 15 ' W, 32 m depth, MZSP 30804, 10 ♀, MZSP 36325, 2 ♀ (sta. 5, 27 / x / 1985); 23 ° 47 ' S 45 ° 10 ' W, 35 m depth, MZSP 30793, 2 ♂, 1 ♀ (Sta. 14, 21 / i / 1986). Rio Grande do Sul, off Albardão, 33 ° 32 ' S 52 ° 18 ' W, 35 m depth, MZSP 19034, 10 ♀ (GEDIP­RS, R. V. W. Besnard sta. 571, 13 / iii / 1969).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	materials_examined	Type locality: BRAZIL; São Paulo; off Ubatuba, 23 ° 29 ' S 44 ° 52 ' W, 38 m depth (Integrated Project IOUSP, R. V. Veliger II, Sta. 8, 28 / x / 1985). A complete conchological and anatomical description of this species is provided elsewhere (Simone 2002). In present paper only a formal description for naming this species is presented.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	description	Description: Shell (Figs. 13 – 15): Medium to large size (up to 40 mm), color white, periostracum deciduous. Dorsal surface plane to concave, arched, opaque. Sculpture lacking, except for concentric, low, narrow somewhat uniform undulations and growth lines. Protoconch 1 whorl, inlaid, located approximately in center of posterior edge. Borders sharp, fragile, with weak remains of pale brown, hairy periostracum. Ventral surface smooth, glossy, white. Septum triangular, protruding ventrally; lateral edges almost straight, at some distance from shell edges; posterior end normally with a shallow concavity and at some distance from shell posterior end. Septum anterior free edge concave, presenting a shallow central notch from which edges diverge gradually towards anterior and lateral, somewhat straight; left insertion in shell simple; right insertion marked by a somewhat deep and narrow notch. No clear muscle scar. Inner anatomy: Already described in Simone (2002). The some complements follows. 1) Odontophore muscle m 12, a small pair of muscles, originating in odontophore cartilages in a small portion by side of m 6 (horizontal muscle) anterior region, running free towards ventral and lateral, inserting in short distance in subradular membrane inner surface. 2) Female genital papilla somewhat tall, in posterior surface a pair of broad folds running longitudinally close from each other, between both a narrow furrow, each one surrounding distal, narrow genital pore; an additional left­dorsal, longitudinal, low fold, originating gradually in papilla base, disappearing gradually at some distance lateral from genital pore (Fig. 112). Habitat: Almost invariably within empty gastropod (bivalve sometimes) shells, from intertidal to 73 m depth.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	distribution	Distribution: Central and Southeast coast of Brazil (Bahia to Rio Grande do Sul).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	description	Measurements of shells (in mm): MZSP 36325: 1) 18.4 by 14.0, 2) 19.1 by 15.3; MZSP 30795: 24.1 by 18.0; MZSP 30790: 27.3 by 20.0. Holotype see type list.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	etymology	Etymology: The specific epithet refers on the living habit inside empty shells, being intra meaning inside, and testa meaning shell from the Latin.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	materials_examined	Material examined: Types and those listed in Simone (2002).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF4FFB2FEFCF9D44AF9F9A6.taxon	discussion	Discussion: Crepidula intratesta has been considered as the Brazilian occurrence of C. plana. However, based on the anatomical difference with the C. plana specimens collected from the neotype locality, and further arguments given by Collin (2000), the specific separation becomes necessary. This description was considered premature in by Simone (2002), but is provided here. A more complete morphological differentiation is given in the section of discussion of characters. However, the more outstanding differences are the C. intratesta longer osphradium, with more filaments; endostyle simple (not divided along its length); kidney with larger hollow chamber, lacking solid dorsal lobe; the thinness of the peri­oral and jaw muscles (mc); the presence of an auxiliary ventral tensor muscle of the radula (m 7 a); salivary gland very shorter, forming a single mass (instead of being coiled); a different arrangement of gastric inner folds; the penis with shorter terminal papilla; pallial oviduct with fewer seminal receptacles; papilla of female pore with different folds (Figs. 66, 112). Although all species of the “ C. plana complex ” potentially can show a concave dorsal surface, this apparently is rare. I have not seen any specimen with this shell morphology, except some specimens of C. plana. Crepidula intratesta almost invariably has the concave dorsal surface, which easily differentiate it from the other species. This shell morphology has the shell septum protruding by the ventral shell surface. It is undoubtedly a consequence of the habitat inside empty shells (mostly gastropods). Further anatomical discussion and distinction is provided by Simone (2002) and herein, in the following section. However, it is interesting to establish that the anatomical difference between C. intratesta, and particularly with C. protea, is relatively small. The differences remain in the conchological features and in developmental attributes (C. protea most probably is not a protandric hermaphrodite, but a dioic).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	materials_examined	Type locality: BRAZIL; Santa Catarina; Bombinhas, Enseada de Zimbros 27 º 06 S 48 º 30 W (otter trawl, 2 – 5 m depth, xii / 1993, Tarasconi leg.).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	diagnosis	Diagnosis: Shell occurring intertidal in Santa Catarina coast. Shell whitish, with periostracum persistent covering most of shell. Siphonal pallial fold broad and wide. Pericardium constricted in middle portion, being narrow in its posterior half. Osphradium occupying about 5 % of pallial aperture, bearing about 10 filaments close from each other. Pallial oviduct having 7 seminal receptacles connected to albumen gland almost in same region. Female genital papilla lacking folds, broad, irregular, inflated.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	description	Description: Shell (Figs. 7 – 9): Of medium size (up to 20 mm), white, convex, flat, surface opaque. Protoconch not seen (eroded). Periostracum heavy, rich in hair, color pale brown, lost in older regions but generally covering most of shell. Sculpture lacking, except concentric undulations and growth lines. Septum somewhat short, wide, triangular, curved septum lateral insertions slightly far from shell outer edges, mainly at right. Septum anterior edge with a wide central notch, its right edge almost straight, its left edge curved, convex; another narrower notch in left end weakly deeper. Inner surface glossy, white, smooth. Head­foot (Figs. 97, 103): General characters similar to those of C. margarita, differences and notable features following. Tentacles tip weakly bifid. Eyes dark, very small, located on very short ommatophores in level between basal and middle thirds of tentacles lateral margin. Head and neck little shorter than foot length. Columellar muscle very reduced, contours anterior border of shell septum, more concentrated at right (Fig. 97). Anterior edge of foot, with pedal gland furrow, simple. Mantle organs (Figs. 98 – 101): Characters similar to those of C. plana, remarks following. Mantle border special arrangement of folds (in middle region of pallial cavity aperture) very broad, covering anterior end of gill, and exceeding beyond mantle border (Figs. 99, 100); decreasing gradually towards left, disappearing in middle level of osphradium. This fold possesses a broad and shallow central furrow. Dorsal shell muscle well developed (Fig. 98: dm), relatively large. Lateral shell muscle reduced, almost absent. Pallial cavity aperture occupies almost half of anterior half of shell border turned to right (if shell compared with a clock, in dorsal view and with head occupying 12 oclock, pallial aperture begins in 9: 30 and finishes in 3 oclock) (Figs. 98, 99). Pallial cavity length about same of total length of animal (Figs. 98). Osphradium small, length about 1 / 6 of pallial aperture length. Osphradium leaflets tall, tip rounded, close from each other, somewhat thick, varying around 11 in number (Fig. 100). Gill filaments triangular base short, extending by about 1 / 5 of filament length (Figs. 100, 101). Endostyle (Figs. 99, 100: en) simple. Hypobranchial gland thin, white, more developed in left side of intestine. Visceral mass (Figs. 98, 99): Shorter and broader than that of C. margarita. Circulatory and excretory systems (Fig. 102): Characters very similar to those of C. atrasolea, remarks following. Pericardium right region broader, with auricle curved, possessing a blunt angle in its middle anterior region. Kidney posterior­right region with 2 – 3 broad, tall, longitudinal folds in dorsal surface; these folds running towards anterior covering left surface of rectum, bearing longitudinal folds; in anterior­left region renal issue covering only dorsal surface, having oblique folds, some penetrating in adrectal sinus. Adrectal sinus continuous to kidney, surrounding rectum up to short distance of anus, gradually decreasing. Digestive system (Figs. 103 – 105):. Buccal mass extending little posterior to proboscis. Odontophore muscles (Fig. 104): m 7 pair with insertion inside radular sac, connected with each other by about half of their length; m 11 pair present. Radula extending little beyond odontophore length. Radula (Fig. 34): rachidian tooth tall, narrow, central cusp large and sharp, single secondary cusps, no basal cusps but pair of lateral reinforcements on its borders; lateral tooth broad, curved internally, with about eight triangular cusps, medial cusp larger, apical, turned towards median, cusps somewhat similar sized, disappearing about in middle region of tooth, remaining a slight thick border; both marginal teeth long, curved, tall, sharp pointed tip, about seven cusps in their inner­apical margin; inner marginal tooth with about double width than outer marginal tooth. Salivary glands narrow, (Fig. 103), length longer than of haemocoel length, running almost straight along haemocoel, becoming broader in region posterior to nerve ring. Stomach (Fig. 105) similar to that of C. atrasolea, except for 1) insertion of esophagus somewhat close to posterior end of stomach; 2) posterior duct to digestive gland very much narrow, simple, running towards posterior; 3) anterior duct to digestive gland broad, dichotomic only after some distance. Stomach inner surface with a single, narrow, pair of folds running along ventral surface of style sac; these folds running in opposite side from each other in region just anterior to anterior duct to digestive gland, surrounding origin of style sac, fading in dorsal surface. Digestive gland pale beige in color. Intestine similar in attributes than that of C. atrasolea, except for strongest U­shaped loop of rectum exposed in pallial cavity (Figs. 100, 105). Genital system: Development: All examined specimens females and larger than 15 mm. No males available. Female (Fig. 106): Albumen gland narrower, differing little from visceral oviduct. About 7 seminal receptacles inserted in right side of albumen gland, reunited in a short region. Seminal receptacles duct slender and long. Capsule gland narrower, somewhat triangular, inner duct broad, flat, straight; walls slightly thin. Vaginal tube originating from anterior­left region of capsule gland; running obliquely to capsule gland towards right, narrow; length little shorter of that of capsule gland; vaginal tube inner surface with 7 – 8 longitudinal, very narrow folds. Genital papilla tall, situated at sort distance of anterior region of albumen gland, at long distance from anus; its inner surface continuous with vaginal tube folds. Papilla broad, blunt, anterior half semispherical, posterior surface with irregular folds Genital pore a transversal, terminal slit with edges tall and thick. Central nervous system: With normal characters as remainder known Crepidula (Simone 2002), located posterior, far removed from buccal mass, close to visceral mass. Habitat: Intertidal rocks.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	distribution	Distribution: Brazilian coast of Santa Catarina.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	description	Measurements of shells (in mm): MZSP 35831: 16.3 by 14.0; MZSP 35832, ♀ 2: 16.0 by 13.4; ♀ 3: 19.4 by 14.0.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	etymology	Etymology: The specific epithet came from the Tupy language, pyguaia, meaning concave, and allusion to the possible extreme form of some specimens.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	materials_examined	Material examined: Types.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF6FFBDFEFCF9744BC4FAE6.taxon	discussion	Discussion: Crepidula pyguaia is similar to the other congeneric species from Western Atlantic. Differs mainly in flat, concave shell, somewhat rounded outline, and by heavy periostracum preserved in youngest region. The characteristic uniform white color is also distinctive, since the remaining species are usually brownish. The anatomical characters also corroborate with the specific separation, mostly explored above. The most important are the longer osphradium, with filaments closer to each other; the shorter triangular base of the gill filaments; the curved fashion of the auricle; the longer salivary glands; the different conformation of gastric ducts to digestive gland (simpler and narrower); and the strongest curve of the U­shaped portion of rectum. However, the deeper differences are in the characters of the pallial oviduct, such as the narrow albumen gland situated almost perpendicularly to the capsule gland; the seminal receptacles in a larger number, reunited forming a single mass, and the genital papilla blunt, almost spherical. C. pyguaia has been identified as C. protea, a species re­described in Simone (2002) occurring in deeper waters (generally on other shells), with taller and more convex shell, lacking periostracum, and more colorful.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	description	Paratypes: BRAZIL. Rio de Janeiro; ANSP 19462, 1 shell (ex­Smithsonian, USEE); Casemiro de Abreu, Rio das Ostras, Joana beach, MNRJ 9517, 5 specimens (A. Coelho col. ii / 1971); Búzios, Raza beach, MNRJ 9516, 1 shell (L. R. Tostes & A. Coelho col., xii / 1974); Cabo Frio, Arraial do Cabo, MNRJ 3366, 4 shells (H. S. Lopes col., iii / 1950), Forno Beach, MNRJ 2337, 2 ♀ (A. Coelho & S. Ypiranga col., i / 1960), Prainha, MZSP 42053, 10 ♀ (Simone & Costa col., 18 / iii / 2003); Niterói, Boa Viagem beach, MNRJ 5480, 1 shell (H. S. Lopes col.), MNRJ 7464, 18 ♀ (H. Travassos & H. S. Lopes col., 9 / iii / 1953), Itaipu beach, MNRJ 2336, 1 ♂, 4 ♀ (A. Coelho col., 1959), MZSP 28737, 1 ♀ (Simone col., 12 / vii / 1997); Rio de Janeiro, off Santana Island, 22 º 30 ' S – 41 º 23 ' W 22 º 43 ' S – 41 º 40 ' W, 48 m depth, MNRJ 9518 (B. Prazeres & O. Silva col. 15 – 25 / x / 1963).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	materials_examined	Type locality: BRAZIL; Rio de Janeiro; Niterói, Boa Viagem beach, 22 ° 56 ' S 43 ° 12 ' W.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	diagnosis	Diagnosis: Shell occurring intertidal in Rio de Janeiro coast. Shell whitish, with periostracum persistent covering most of shell. Siphonal pallial fold low and narrow. Pericardium constricted in middle portion, being narrow in its posterior half. Osphradium occupying about 15 % of pallial aperture, bearing about 20 filaments close from each other. Pallial oviduct with 5 seminal receptacles connected to albumen gland almost in same region. Female genital papilla with a pair of folds in posterior side, disappearing at some distance from pore; papilla tip pointed.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	description	Description: Shell (Figs. 22 – 25): Of medium size (up to 20 mm), white, convex, flat, surface opaque. Protoconch eroded. Periostracum heavy, rich in hair, color pale brown, lost in older regions but generally covering most of shell. Sculpture lacking, except shallow concentric undulations and growth lines. Septum somewhat short, wide, triangular, curved septum lateral insertions slightly far from shell outer edges, mainly at right. Septum anterior edge with a wide central notch, its right edge almost straight, its left edge curved, convex; another narrower notch in left end weakly deeper. Inner surface glossy, white, smooth. Head­foot (Fig. 108): Similar features to those of C. pyguaia, tentacles more clearly bifurcated, having a somewhat deep furrow at tip. Mantle organs (Fig. 107): Characters closely similar to those of preceding species. Remarkable features following. Pallial cavity length of larger specimens about 90 % of total animal length. Siphonal fold at mantle border shorter and narrower, its right end low, fused with remaining mantle edge. Osphradium with about 20 filaments; length about 15 % of pallial cavity aperture; each filament slightly cylindrical, close with each other. Endostyle posterior half running separated from ctenidial vein, running along mantle surface adjacent to it, slightly ventral to ctenidial vein up to gill end. Visceral mass and circulatory­excretory systems: Same characters than those of C. pyguaia, including sudden narrowing in its left half. Digestive system: Morphological attributes similar to those of C. pyguaia. Radula (Fig. 33) also similar, except by rachidian slightly narrower, having two pairs of secondary cusps; marginal with seven cusps, second cusp larger and terminally disposed; marginal teeth with six secondary cusps in sub­terminal inner edge. Genital system: Male (Figs. 108, 109): General features similar to those of preceding Crepidula. Remarkable characters following. Testis whitish, located in anterior region of ventral branch of visceral mass, additionally extending towards posterior along its left side, this region forming successive and decreasing digitiform acina. Seminal vesicle slightly small, bearing 3 – 4 whorls, narrowing gradually. Penis somewhat long, terminal papilla slender and long, with about half of remaining penis length (Fig. 108). Female (Fig. 110): General organization similar to those of preceding species. Remarks following. Albumen gland narrow and short. Seminal receptacles rounded, number of 5 decreasing towards anterior; ducts very narrow, connected to albumen gland anterior­right side almost in same region. Capsule gland narrow. Vaginal tube broad and long. Internally low longitudinal, narrow folds. Genital papilla tall, with a pair of longitudinal folds running at some distance from each other along posterior surface, finishing at some distance from pore. Papilla tip somewhat pointed. Genital pore a narrow, sub­terminal slit. Anus in basal level of pallial oviduct. Measurements (in mm): MNRJ 7464> ♀: 34.0 by 23.5; <♀: 11.0 by 9.0;> ♂: 15.0 by 9.7; ♂ 3: 12.9 by 10.0; ♂ 4: 22.7 by 17.4.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	distribution	Distribution: Known for coast of Rio de Janeiro. Habitat: Intertidal rocks up to 48 m depth.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	etymology	Etymology: The specific epithet refers to the geographic occurrence of the species, i. e., the region of the Rio de Janeiro. The people from the city of Rio de Janeiro are known as “ carioca ”.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	materials_examined	Material examined: Types.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFF9FFBFFEFCFAA64D95F9CE.taxon	discussion	Discussion: Crepidula carioca is closely similar to C. pyguaia, both, in conchological and anatomical features. In the shell they are almost indistinguishable. Crepidula carioca normally has less periostracum, but this feature disappears in dead samples. The number and type of anatomical character, most explored above, based the specific separation of C. carioca from C. pyguaia. The considered more important are: 1) the longer osphradium (about 15 % of pallial cavity aperture in C. carioca, wile C. pyguaia has about 5 %); 2) osphradium bearing more filaments (about 20 in C. carioca and about 10 in C. pyguaia in larger specimens of equivalent size); 3) fewer seminal receptacles (5, while C. pyguaia has 7); 4) anus closer to pallial oviduct; 5) female genital papilla with different fashion, having a pair of longitudinal papillae in posterior surface and a pointed tip. Crepidula pyguaia and C. carioca are close related species, but they are apparently separated geographically, since no Crepidula of similar feature occur in São Paulo coast, as I have consulted in all local collections. Crepidula pyguaia and C. carioca differ from the other congeneric species in having a persistent periostracum, whitish shell color, and in occurring in shallow waters (intertidal), these characters can easily and quickly identify any sample. But for differentiating both only based on shell samples it is necessary taking into consideration the locality.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFBFFB8FEFCF95C4B7FFD8E.taxon	description	Synonymy see Simone (2002: 32). Complement:	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFBFFB8FEFCF95C4B7FFD8E.taxon	materials_examined	Additional material examined: BRAZIL; Rio Grande do Sul; off Sarita, ANSP 244118. 5 shells (Fishing boats col. 1959. E. C. Rios leg.); off Rio Grande, 32 º 30 S 52 º 00 W, ANSP 355327, 35 specimens (voucher material of Hoagland; Hoagland, Hoagland & Davis col., 20 / xii / 1981). URUGUAY; Rocha; La Paloma, 34 º 40 S 54 º 09 W, ANSP 410440, 2 shells (Naide & Naide col., iii / 1959; E. I. Duarte leg.); off Maldonado, ANSP 220712, 1 shell (B. R. Bales col.; 1958).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFCFFB8FEFCFD1C4895FB19.taxon	materials_examined	Additional material examined: ARGENTINA; off Mar del Plata, on commercial mussel banks, 20 – 30 m depth, ANSP 338926, 2 shells (Victor Scarabino col. vi / 1975; E. Hoagland leg.)	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFCFFB9FEFCFAF64C08FA46.taxon	description	Synonymy see Simone (2002). Complement:	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFCFFB9FEFCFAF64C08FA46.taxon	description	The examined specimens have been erroneously identified as Crepidula convexa Say, 1822 in my previous paper (Simone, 2002), which is here corrected. The change of the concept was based on the examination of voucher specimens at BMNH as explained following. There are some samples of Crepidula convexa in the visited museums; however, coincidently few them have precise locality data. Voucher material of Reeve (1859) (BMNH 1829) has no locality at the label. Some samples (BMNH, ANSP 357830) show that the species occur in the north­western Atlantic, sometimes referred for estuary. The shell of C. convexa is very characteristic (Figs. 126 – 1295) in being small (about 10 mm), dark reddish colored, highly convex (tall for the genus) and with a projected posterior beak, keeping the protoconch away from substrate and normally distant from the posterior shell border (Fig. 127). The shell septum is weakly and centrally concave at its edge (Fig. 128). Additionally, a conspicuous feature is the large muscle scar present in right side, just dorsal to right septum insertion (Fig. 126). A sample with soft parts was examined (BMNH from New Jersey), revealing a huge dorsal muscle. These characters show that C. convexa is not actually close to the C. plana complex, and some distinctive anatomical attributes are present. On the other hand, Crepidula glauca, which has been considered a form of C. convexa (e. g., Warmke & Abbott, 1961; Abbott, 1974), appears to be a separated species. This conclusion is based on the examination of voucher lot of Reeve (1859) (BMNH no locality) (Figs. 123 – 125). The shells are flat, wide, whitish, with apex fused with shell edge, sigmoid septum edge, and with the muscle scar shallow and small. These characters are common in the C. plana complex. In being the examined specimens virtually identical to the Reeves lot, the systematics of these species can be resolved, considering C. glauca a valid species, separated from C, convexa, possessing the shell and anatomical attributes described here and by Simone (2002). Additional material examined: No locality, BMNH, 4 shells (voucher of Reeve, 1859). VENEZUELA; Isla Margarita, off Morro de Pto. Moreno, 13 – 17 m depth, ANSP 240085, 1 dry specimen (Wesley M. Heilman leg. 16 / ii / 1959; sta. 28). Material examined of Crepidula convexa: No locality; BMNH 1829, 4 shells (Voucher of Reeve, 1859); BMNH, 3 shells (Van Couvers Lsd); BMNH, 4 shells (figured specimen; H. Cuming collection). UNITED STATES OF AMERICA; Massachusetts; Plymouth, BMNH, 12 shells. Connecticut; Bridgeport, Fairfield county, Long Island sound, St. Marys estuary, 41 º 10 N 73 º 10 W, ANSP 357830, 1 shell (Hoagland & Hoagland col. 1982). New York; Northport, BMNH 1838, 9 shells (Winckworth colln.). New Jersey; Cape May, Wildwood, BMNH 20020070, 6 specimens (R. Collin col. 13 / vi / 1999).	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFDFFBAFEFCF9D4484DFD3E.taxon	description	Synonymy see Simone (2002: 38). Complement:	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFDFFBAFEFCF9D4484DFD3E.taxon	materials_examined	Additional material examined. UNITED STATES OF AMERICA; Florida; St. Petersberg, MZSP 35843, 14 ♀ (T. Bert col. 1997, R. Collin leg. & id.). N. B.: The lot ANSP 411047 is 3 shells almost certainly of C. fornicata, however, the collect data is URUGUAY; Rocha, La Paloma 34 º 40 S 54 º 09 W (E. Duarte leg iii / 1959). It is possible that some change of data happened and this species does not occur in the south Atlantic.	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
03DBF911FFFEFF94FEFCFCEC4BA6FB96.taxon	discussion	Discussion of the characters	en	Simone, Luiz Ricardo L. (2006): Morphological and phylogenetic study of the Western Atlantic Crepidula plana complex (Caenogastropoda, Calyptraeidae), with description of three new species from Brazil. Zootaxa 1112 (1): 1-64, DOI: 10.11646/zootaxa.1112.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1112.1.1
