Xylergatoides asper (Bates, 1864)

Xylergatoides asper (Bates, 1864) View in CoL

( Figs 73 View FIGURES 71–80 –94)

Description

Larva ( Figs 71–89 View FIGURES 71–80 View FIGURES 81–89 ). Length: 19–21 mm.

Body ( Figs 81–83 View FIGURES 81–89 ) soft, smooth, yellowish white, subcylindrical, slightly depressed dorsoventrally; narrowed from mesothorax to abdominal segment VI abdominal segments VII–IX wider forming a flattened flap on each side. Coloration based in other specimen; Figs 83–85 View FIGURES 81–89 represent larva just moulted. Head light yellow on distal third (exposed area), brownish laterally and ventrally; mouth frame brown; mandibles dark brown; labrum brown on basal 2/3; maxillae and labium membranous, partially brownish with brown palpi. Pubescence dense, fine and yellowish to ferruginous, denser and longer dorsally and ventrally on prothorax, and laterally on meso-, metathorax and all abdominal segments including abdominal apex. Ambulatory ampullae irregularly rounded, tuberculate.

Head ( Figs 71–72 View FIGURES 71–80 ) moderately convex, deeply retracted into prothorax, only anterior third exposed, longer than wide, narrowed and slightly prominent posteriorly; posterior margin slightly prominent and rounded. Median frontal endocarina short, not reaching epistomal margin; dorsomedian cranial duplicature visible; one longitudinal narrow groove on each side reaching almost whole head length. Frontal suture distinct only at antennal base. Epistomal margin ( Figs 71, 73 View FIGURES 71–80 ) almost straight; three pairs of epistomal setae of different sizes: two shorter laterally near each epistomal lobe, and one longer more internally, distant from middle; dorsally, each side with four pairs of frontal setae (one shorter); three lateral setae below each antenna and a group of three short setae on each side, near anterior part of longitudinal sclerotized grooved band. Stemmata absent, even translucent lens. Foramen entire. Hypostomal line elongate, almost reaching foramen. Gular lines absent; gular area with two pairs of setae. Antennae ( Fig. 75 View FIGURES 71–80 ) short, extensible, slightly sclerotized and with two wide and slightly elongate antennomeres; distal antennomere with one dorsal campaniform sensillum near base, and apex with one cupuliform membranous sensorium, sclerotized basally, and two long and four short thick setae. Clypeus ( Fig. 73 View FIGURES 71–80 ) short, band-shaped with a transverse median irregular brownish band. Labrum ( Fig. 73 View FIGURES 71–80 ) 1.6 times wider than long; anterior margin widely rounded; lateral margins slightly narrowed on basal half; long and thick setae marginate on distal fourth. Epipharynx ( Fig. 74 View FIGURES 71–80 ) densely covered with thick setae directed to middle; median basal region with microspines and campaniform sensilla; basal half with one sclerite on each side (tormae). Mandibles ( Figs 84–89 View FIGURES 81–89 ) strongly sclerotized, symmetrical; apex widely rounded, declivous dorsally; one subapical, rounded, weak dorsal lobe; internally keeled near apex and striated at base; distal external half with two irregular, rounded, striate concavities; external face striate and with two setae near base. Maxillolabial complex ( Figs 72, 76, 77 View FIGURES 71–80 ) partially membranous; submentum, maxillary articulating areas and cardines fused; maxillary articulating areas with setae (broken and represented by punctures in Fig. 77 View FIGURES 71–80 ). Distal part of maxilla: stipes with wide brownish, inclined, transverse band; long setae above inclined band and lateral margins; mala slightly sclerotized, wider and shorter than palpus, with rounded apex and numerous long and thick apical setae dorsally and ventrally. Palpifer slightly sclerotized, except apex, with long setae more concentrated ventrally and with microspines dorsally. Maxillary palpi trimerous; palpomeres with complete rings pigmented; first palpomere elongate with crown of setae near apex; second palpomere almost as long as wide, with five setae and one campaniform sensillum ventrally and one seta dorsally; distal palpomere ( Fig. 78 View FIGURES 71–80 ) with one campaniform sensillum ventrally, one laterointernal dorsal seta, one dorsal palpiform seta, and some peg-shaped sensoria at apex. Distal part of labium: mentum short, transverse, with six pairs of short setae near base. Prelabium well separated; prementum longer than mentum, narrowed and sclerotized at basal half; palpiger partially membranous, rounded laterally with many long setae; ligula elongate, narrow, with distal margin rounded, almost as long as palpi covered with thick short setae. Labial palpi dimerous; palpomeres elongate, with complete rings pigmented; first palpomere with crown of long setae near apex and one ventral campaniform sensillum; distal palpomere with one ventral campaniform sensillum and some peg-shaped sensilla at apex. Hypopharynx ( Fig. 78 View FIGURES 71–80 ) soft and swollen, marginate anteriorly by long setae; one anterior band of long setae near middle, parallel anterior margin; several campaniform sensilla near middle; one longitudinal, wide band of microspines near middle; one lateral sclerite each side on basal half (tormae).

Prothorax trapezoidal, convex dorsally and flat ventrally; dorsally with wide band of yellowish setae anteriorly and laterally; one small yellowish patch on each side anteriorly; larger transverse basal patch covered with microtrichia on basal third of pronotum. Ventrally prothorax with one small yellowish patch on each side and covered with short setae (shorter than dorsal). Meso- and metathorax transverse, together shorter than prothorax; each with one dorsal and one ventral transverse band of setae and one rounded setose area on each side. Mesothorax with a lateroanterior elliptical spiracle with many lateral marginal chambers in both sides ( Fig.79 View FIGURES 71–80 ).

Abdominal segments, each with one dorsal and one ventral transverse band of setae and one rounded setose area on each side; segments VII–VIII wider; abdominal segments VII–IX with lateral flat and lateral rounded tubercle, slightly sclerotized; segment IX ( Fig. 80 View FIGURES 71–80 ) slightly narrower than VIII, subtriangular, with a lateral constriction near middle; setose near apex and with one tiny sclerotization near each constriction; segment X apical, rounded with trilobed apex. Segments I–VIII with an elliptical spiracle on each side; segments I–VII, each with one dorsal and one ventral pair of irregular rounded tuberculate ampullae; dorsal and ventral abdominal intersegmental zones do not meet each other and overlap.

Pupa (female) ( Figs 90–91 View FIGURES 90–92 ). Length: 16 mm.

Coloration yellowish cream. Head partially visible from above. Integument with sclerotized spines, each with one basal ferruginous seta; spines increasing in size to body apex. Frons with five pairs of setigerous spines on each side and one pair at base of each antenna; clypeus with three pairs of setigerous spines, labrum with four smaller setigerous spines with thinner setae; trochanter with a crown near apex. Antennae separately looped back, loop shorter than elytra, reaching ventrite III.

Pronotum transverse, narrowed anteriorly; lateral margins forming one rounded and prominent tubercle near basal third and another smaller on hind angles; grooved longitudinal-medially; a transverse row of setigerous spines at middle near anterior margin; setigerous spines dispersed below previous row; a well-developed setigerous spine on each lateral rounded lobe and spines dispersed on basal third. Mesonotum transverse with posteromedial area slightly prominent, slightly grooved longitudinal-medially, with four small setigerous spines on each side. Metanotum almost as wide as long, grooved longitudinal-medially; one irregular inclined band of setigerous spines. Elytra surpassing ventrite III.

Abdomen. Tergites I–VI transverse, grooved longitudinal-medially, decreasing in length apicad, with one wide band of well-developed setigerous spines near distal margin, interrupted on middle; tergites II–VI also with spines in a rounded area at middle, near anterior margin; basal band increasing in length apicad; tergite VII narrower and elongate, narrowed apicad with rounded apex, with many setigerous spines near middle; segment VIII narrower, transverse, with two setigerous spines on each side, near middle of lateral margins and four longer dorsal; ventrally segment VIII with 3–4 small setigerous spines; segment IX narrower than anterior, almost as wide as long, dorsally with two couples of setigerous setae (one setae shorter), and ventrally with two short spines on each side and three tiny setigerous setae at middle; X short, transverse with apex trilobed, dorsally with one pair of dorsal spines on each side (apical longer) and ventrally with four curved setigerous spines on each side. Functional spiracles laterally on tergites I–VI.

Material examined. Brazil. São Paulo: Peruíbe , 27–29.IV.1981, Exp. MZUSP col., 1 larva reared to adult, 2 larvae and 1 pupa fixed ( MZSP 8730 View Materials ) .

Remarks. Larvae of Xylergatoides asper is characterized especially by the head slightly narrowed posteriorly, with two longitudinal dorsal narrow grooves; epistomal setae not equidistant: two shorter laterally near each epistomal lobe, and one longer more internally, distant from middle; antennae with two antennomeres; ambulatory ampullae irregularly tuberculate; body narrowed from mesothorax to segment VI; abdominal segments VII–IX wider forming lateral flaps; and tergite IX with one tiny sclerotization near each lateral constriction.