Review of the genus Malacoctenus (Actinopterygii: Labrisomidae) from the Southwestern Atlantic, with description of two new species
Author
Carvalho-Filho, Alfredo
Author
Sazima, Ivan
Author
Lima, Sergio Maia Queiroz
Laboratório de Ictiologia Sistemática e Evolutiva, Departamento de Botânica e Zoologia, Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.
Author
Almeida, Daniel
0000-0002-7178-2498
Universidade Federal do Rio de Janeiro, Museu Nacional, Setor de Ictiologia, Departamento de Vertebrados, Quinta da Boa vista, s / n, 20940 - 040, Rio de Janeiro, RJ, Brazil. & almeida. d @ gmail. com; https: // orcid. org / 0000 - 0002 - 7178 - 2498 & ricdias 77 @ gmail. com; https: // orcid. org / 0000 - 0003 - 1087 - 2227 & mrbritto 2002 @ yahoo. com. br; https: // orcid. org / 0000 - 0002 - 0611 - 6923 & almeida. d @ gmail. com; https: // orcid. org / 0000 - 0002 - 7178 - 2498 & Laboratório do Oceano, Departamento de Ecologia, Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.
almeida.d@gmail.com
Author
Mendes, Liana
0000-0002-7178-2498
almeida. d @ gmail. com; https: // orcid. org / 0000 - 0002 - 7178 - 2498 & Laboratório do Oceano, Departamento de Ecologia, Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.
almeida.d@gmail.com
Author
Dias, Ricardo Marques
0000-0002-7178-2498
Universidade Federal do Rio de Janeiro, Museu Nacional, Setor de Ictiologia, Departamento de Vertebrados, Quinta da Boa vista, s / n, 20940 - 040, Rio de Janeiro, RJ, Brazil. & almeida. d @ gmail. com; https: // orcid. org / 0000 - 0002 - 7178 - 2498 & ricdias 77 @ gmail. com; https: // orcid. org / 0000 - 0003 - 1087 - 2227 & mrbritto 2002 @ yahoo. com. br; https: // orcid. org / 0000 - 0002 - 0611 - 6923 & ricdias 77 @ gmail. com; https: // orcid. org / 0000 - 0003 - 1087 - 2227
almeida.d@gmail.com
Author
Britto, Marcelo R.
0000-0002-7178-2498
Universidade Federal do Rio de Janeiro, Museu Nacional, Setor de Ictiologia, Departamento de Vertebrados, Quinta da Boa vista, s / n, 20940 - 040, Rio de Janeiro, RJ, Brazil. & almeida. d @ gmail. com; https: // orcid. org / 0000 - 0002 - 7178 - 2498 & ricdias 77 @ gmail. com; https: // orcid. org / 0000 - 0003 - 1087 - 2227 & mrbritto 2002 @ yahoo. com. br; https: // orcid. org / 0000 - 0002 - 0611 - 6923 & mrbritto 2002 @ yahoo. com. br; https: // orcid. org / 0000 - 0002 - 0611 - 6923
almeida.d@gmail.com
Author
Gasparini, João Luiz
0000-0003-1087-2227
ricdias 77 @ gmail. com; https: // orcid. org / 0000 - 0003 - 1087 - 2227
ricdias77@gmail.com
text
Zootaxa
2020
2020-07-24
4819
3
499
520
journal article
8955
10.11646/zootaxa.4819.3.4
7026c184-1da2-4249-b0f1-083f2bf2cd90
1175-5326
4397065
84BBE642-5413-4AC5-A644-98D228844E98
Malacoctenus brunoi
Guimarães, Nunan & Gasparini, 2010
English Name: Trindade Scaled-Blenny
Portuguese (Brazilian) Name: Macaquinho de Trindade
(Figure 6-A)
Malacoctenus
sp.
Nunan 1992
;
Gasparini & Floeter 2001
.
Malacoctenus oceanicus
Guimarães
et al
. 2001
(
nomen nudum
).
Malacoctenus
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.