Malacoctenus brunoi Guimarães, Nunan & Gasparini, 2010

Malacoctenus brunoi Guimarães, Nunan & Gasparini, 2010 View in CoL

English Name: Trindade Scaled-Blenny

Portuguese (Brazilian) Name: Macaquinho de Trindade

(Figure 6-A)

Malacoctenus View in CoL sp. Nunan 1992; Gasparini & Floeter 2001.

Malacoctenus oceanicus Guimarães et al. 2001 ( nomen nudum).

Malacoctenus View in CoL sp. n. Gasparini 2004.

Diagnosis. Malacoctenus brunoi can be distinguished from its southwestern Atlantic congeners by the following combination of characters: body elongated (depth 19–22 % SL versus 22–26 % SL in M. lianae sp. n. and M. zaluari sp. n., and 24–28 % SL in M. delalandii ), lateral line scales 60–66 ( versus 51–53 in M. zaluari , 54–68 in M. lianae , and 48–56 in M. delalandii ), and the presence of two longitudinal rows of dark brown spots aligned on sides of body ( versus presence of dark, triangular-shaped, saddle-like bars on body in M. lianae sp. n. and M. zaluari sp.n. and presence of irregular saddle-like bars in M. delalandii ).

Description: Proportional measurements and counts in Guimarães et al., (2010). Complementary description based on holotype, two paratypes and 64 non-type specimens. Body elongated. Head moderate, snout pointed, forehead steep; eye 25–30% in head length; upper lip separated from snout by deep groove; jaws subequal with about 11 pairs of pointed, slightly curved teeth; a crescent patch of villiform teeth on vomer; palatine toothless; maxillary barely reaching orbit; gill rakers on first arch 3–4 + 7–8; nasal cirrus simple or bifid (rarely triple or absent), arising from posterior border of short tube of anterior nostril and not reaching to posterior nostril when depressed; supra orbital cirri branches 3 (rarely 2 or 4) over each eye, its length varies from smaller to larger than half orbit diameter; nuchal cirri 6–8 (rarely 9) on each comb, paired or with one cirrus less, 13–18 in total, the longest reaching beyond dorsal-fin origin; space between nuchal cirri combs contained 2–3 times in comb´s base. One pore from preopercular canal onto opercle, rarely absent. Pores on ventral side of head: 3–4 mental, 1–2 symphysial and 4–6 interopercular.

Dorsal fin continuous, with three sections: first three spines decrease in length, followed by fourth to eighth or ninth spines progressively longer behind which last spines are successively shorter, the antepenultimate longer than penultimate; last spine length varying from one third to slightly less than half length of first and longest soft ray; soft rays decreasing in height, last one joined to body by a membrane for most of its length. Caudal fin slightly emarginate to slightly rounded with 11 unbranched, segmented rays, followed above and below by a single non-segmented ray and several procurrent spines. Anal fin continuous, the 16 th to 18 th rays the longest; first anal spine length 2/3 to 3/4 of second anal spine; first anal ray almost 1/3 longer than second anal-fin spine; anal-fin membrane notched at tip of each ray; last anal-fin ray not attached to body by membrane. Pectoral fin elongate, fifth or sixth lower rays usually longest. Pelvic fin second ray longer than third, not reaching anus; length of third, inner, shortest pelvic-fin ray, contained 2.5 to 3.0 times in second pelvic-fin ray.

Body covered with cycloid scales except pre-pelvic and immediate surrounding area. Head naked. Breast fully scaled in males and usually naked in females, as in the holotype; breast and belly scales much smaller than body scales. Scales on midline before dorsal fin absent; base of pectoral fin without scales; lateral line complete, running high anteriorly, down-curved below 10 th to 12 th dorsal-fin spines and straight along mid-body posteriorly. All fins naked.

Coloration. Color pattern varies considerably between individuals. Males usually more brightly colored than females.

Color in alcohol: Background varies from grey to tan, five or six dark, rarely seven, triangular saddle-like bars on body, extending to spiny dorsal fin, rarely on fin-rayed dorsal fin. Saddles vary from dark to light brown usually not outlined by dark spots; lower apices of saddles often somewhat constricted below the midline of the body. Interspaces below body-midline rarely uniformly light, often with dark irregular patches and those, with constricted lower apices of saddles, may form a horizontal row of large, irregular blotches. Lower sides of body light to tan often dark reticulated, or irregular markings. Vertical fins membranes transparent, dark, and/or pale dots on soft rays. Head peppered with dark dots or irregular blotches; snout dark often with two faint pale lines from eye to lip; two, rarely one, dark bars from eye to lower part of head. A light bordered ocellus usually present at the lower portion of the opercle, more conspicuous on males. Pre-pectoral area with faint dark irregular markings.

Color in life: Background varies from white to yellowish or light tan, head and body with many white dots (or without), often with a light green cast overall. Saddle-like bars peppered with green, orange, blue and/or red dots, brighter on males, often outlined by pale dots. Dorsum with interspaces between saddle-like bars varying from greenish to tan. Lower part of body usually with reticulations of same color as saddles, often with dark dots and/or irregular blotches. Two somewhat rectangular whitish bars or lines may be present from eye to upper lip. Eye dark often with a faint to conspicuous white area on lower border, sometimes split in two. A dark somewhat triangular spot behind eye, often with an iridescent blue lower margin, more prominent on males. Opercular ocellus outlined with a bright pale line on upper part, more colorful on males and paler on females, on which occasionally are dull to bright yellow. Top of head often with greenish, red and/or blue reticulation. Dorsal fin transparent, the soft rays of vertical fins often with dark and/or pale marks, usually arranged in series. Pelvic fins light yellow to tan on females, orangish to yellowish on males; pectoral fins pale with series of darks dots, lower-fin rays darker on females and orangish to yellowish on males.

As a final remark, we follow the hypothesis of four distinct lineages for the Malacoctenus triangulatus group ( sensu Dias et al., 2019) and regard the oceanic Malacoctenus brunoi as a taxonomic entity distinct from the coastal Malacoctenus zaluari sp. n. as described herein.