Enneanectes macrops, Rosenblatt, Richard H., Miller, Elizabeth C. & Hastings, Philip A., 2013

Rosenblatt, Richard H., Miller, Elizabeth C. & Hastings, Philip A., 2013, Three new species of triplefin blennies of the genus Enneanectes (Teleostei, Tripterygiidae) from the tropical eastern Pacific with a key to Pacific species of Enneanectes, Zootaxa 3636 (2), pp. 361-373 : 366-369

Enneanectes macrops sp. nov.

“Mexican Triplefin”

( Figs. 3 & 4 )

Enneanectes “species A”: Robertson & Allen 2008; Erisman et al. 2011.

A total of 399 specimens from 28 collections, all from the Pacific waters of Mexico.

Holotype. SIO 11-394 (formerly UCLA 58-10), 36.6 mm SL male; Mexico, Nayarit, Ensenada Chacala, off Punta Chacala; bottom of sand at foot of boulder slope at a depth of 12 m; collected 26 Jan. 1958 by F. Munz, J. Stephens & J. Quast.

Paratypes. Sinaloa: LACM 9333-5 (formerly UCLA 51-20), Mazatlán, 8 (29.3–37); SIO 11-397 (formerly UCLA 51-52), Mazatlán, Islas Venados, 10 (25–37); SIO 11-398 (formerly UCLA 51-29), Mazatlán, Islas Venados, S. end of Isla Lobos, 10 (25.7–37.4); SIO 11-399 (formerly UCLA 51-54), Mazatlán, Isla Venado, shoreward side of isthmus, 8 (26–36); SIO 11-400 (formerly UCLA 51-58), Mazatlán, Islas Venados, 10 (33–38).

Nayarit: SIO 11-394 (formerly UCLA 58-10), 1 (34.5), collected with the holotype; SIO 12-62 (formerly UCLA 58-2), Ensenada Chacala, N. side of Punta Chacala, 15 (12.9–37.5); SIO 11-393 (formerly UCLA 58-5), S. edge of small point inside larger point at Chacala Village, 70 (11–37); SIO 12-63 (formerly UCLA 58-11), ¾ mi. S. of point forming S. end of Ensenada Chacala 40 (9.5–28.5). Islas Tres Marias: SIO 62-19-61E, Isla Maria Madre, 18 (12–38); SIO 62-20-61F, Isla Maria Madre, 8 (21–35); SIO 62-55- 61 I, Isla Cleofas, 25 (20.5–38); SIO 62-56-61D, Isla Cleofas, 24 (13–38); SIO 62-58-61F, Isla Maria Magdelena, 4 (21–26); Jalisco: SIO 70-163, Bahia Navidad, 19 (11.3–41.5); SIO 70-165, Bahia Chamela, 12 (10–38); SIO 70-167, Bahia Chamela, 24 (12.5–38); UW 151894, same as SIO 70-167, 1 (34); SIO 70-169, Bahia Banderas, 11 (11.5–32.5); SIO 01-182, Puerto Vallarta, 22 (18–43). Colima: LACM 9051-32, N. of Manzanillo, 4 (23.5–37.3); LACM 50143 (formerly UCLA 56-231), Manzanillo, Ensenada Carrizal, across bay from Manzanillo, 1 (23.6); SIO 70-158, Manzanillo, 7 (19.5–32.5); SIO 12-64 (formerly UCLA 56-232), W. end of Playa de Santiago about 10 miles NW of Manzanillo, 10 (21.5–29.6). Guerrero: LACM 48727-6 (formerly UCLA 52-112), Puerto Marques, near Acapulco, 1 (34); LACM 49967-3 (formerly UCLA 56-18), Acapulco, Isla La Roqueta, 3 (20.8–32); SIO 70-155, Acapulco, White Friar, 31 (18–39.5); CAS 235203, same as SIO 70-155, 2 (33–40); LACM 58002-1, same as SIO 70-155, 2 (30–32); USNM 410091, same as SIO 70-155, 2 (32–36); USNM 65483, Acapulco, 1 (36).

Diagnosis. A thick-bodied species of Enneanectes with a large eye, no enlarged scale in pectoral axil, lower sides body with a prominent brown network outlining scales and lacking horizontal brown lines.

Description. First dorsal fin with three spines; second dorsal fin with 11–13 (11.9) spines; third dorsal fin with 8–10 (8.9) segmented rays. Anal fin with two spines and 16–18 (17) segmented rays. Pectoral fin with 14–16 (15.0) rays; central rays branched with upper 1–2 and lower 7–8 unbranched. Lateral line discontinuous with 16–18 (16.9) pored scales in upper portion and 17–20 (17.9) notched scales in lower portion. Lateral scale rows 31–33 (32.1); scales above pored lateral line 2½; scales below pored lateral line 5½.

Measurements of 26– 46 specimens expressed as thousands of SL (means in parentheses). Head length 326–358 (337); postorbital length 151–177 (162); head depth 155–212 (188); head width 227–270 (251); snout length 97–112 (105); upper jaw length 145–165 (156); eye diameter 95–125 (106); first dorsal spine length 129–170 (147); second dorsal spine length 112–183 (134); third dorsal spine length 85–123 (116); length of third spine of second dorsal 154–191 (176); length of third ray of third dorsal 145–202 (167); length of second dorsal-fin base 286–332 (302); length of third dorsal-fin base 151–186 (172); length of anal-fin base 382–435 (410); distance from pelvic-fin insertion to anal-fin insertion 285–346 (302); pectoral-fin length 282–343 (317); pelvic-fin length 151–236 (176); caudal peduncle length 122–153 (144); caudal peduncle depth 89–112 (94).

Body relatively stout. Head broadly triangular when viewed from above; outline convex from opercle to anterior margin of orbit, slightly constricted at this point; snout broadly rounded. Upper lip well in advance of eye. Profile between upper lip and eye with a gradual slope when viewed from side; outline from eye to dorsal-fin origin flat.

Eye large and prominent, placed high on head; entire upper margin entering outline of head; lower margin opposite eighth or ninth pectoral-fin ray. Upper and lower jaws similar in length; upper jaw ending between a vertical from midpoint of eye and rear margin of pupil. Upper one-fourth to one-third of vertical limb of preopercle adnate to opercle. Upper limb of preopercle vertical and straight. Preopercular angle broadly rounded. Shape of rear margin of opercle variable, sometimes evenly rounded, but often flat or concave above level of pectoral-fin base. Rear margin of opercle spiny above pectoral-fin base, smooth below.

Top of head posterior to interorbital area covered with small, closely-set spines. Nasals and entire orbital margin (frontals, lateral ethmoids and infraorbitals) spinose in large specimens. Spination increases with growth: small specimens (25 mm SL and below) have fewer head spines; spines on nasals and infraorbitals present only in large specimens.

Supraorbital cirrus well developed, flaplike with a low distal fringe, a little broader than long, its length about equal to interorbital width. Anterior nostril with a short tube bearing a cirrus on its posterior margin; nasal cirrus flaplike, its length approximately equal to pupil diameter. Posterior nostril oval, lacking a tube or cirrus.

Teeth in jaws conical, recurved and sharply pointed, arranged in setiform bands. Teeth of outer rows in each jaw widely spaced and two or three times as large as inner teeth. Vomerine teeth small, conical and closely set, in two irregular V-shaped rows. No teeth on palatine.

First dorsal-fin spine inserted over level of anterior third of opercle. First dorsal fin low; first spine much shorter than third spine of second dorsal fin; spines graduated, third notably shortest. Small spinules sometimes present along anterior margin of first spine and distal tips of more posterior spines. Outline of second dorsal fin even; first spine only a little shorter than longest spine (third or fourth). Third through ninth spines about equal in length and succeeding spines shorter; last spine slightly less than half as long as third. Second ray of third dorsal fin longest. Middle five to seven dorsal soft rays usually branched, although there may occasionally be as few as four or as many as eight branched rays in third dorsal fin; last element typically double. Anal-fin spines set close together; first from two-thirds to three-fourths as long as second, which is a little more than half as long as first anal-fin soft ray. Posterior rays of anal fin longer than anterior rays. Antepenultimate ray longest, about one and one-eighth times as long as first ray. Longest ray, when depressed, falls about one-half scale short of caudal-fin base. Anal-fin membrane shallowly incised; distal one-fourth of anterior margin of each ray free. Last anal-fin element typically double. Pectoral fin short, extending posteriorly to under penultimate dorsal-fin spine. Though rather pointed in outline, pectoral fin more rounded than in most species of Enneanectes . Pectoral fin typically with one (rarely two) upper unbranched rays, seven branched rays and seven lower unbranched rays (rarely 6 or 8). Pelvic fin short, ending about one-half pupil diameter before anus.

Sides completely scaled; first two scales above lateral line equal in size. Opercular scale patch well-developed, extending ventrally to opposite fourth pectoral-fin ray insertion (opposite lower margin of pupil); three or four scales wide dorsally tapering to one scale wide ventrally. Cheek and pectoral-fin base naked. Belly squamation variable, from completely covered with cycloid scales (including the holotype) to scales present only along sides, to occasional specimens with no belly scales. No enlarged scale in pectoral axil.

Genital papilla of males short, conical, lacking tentacles. Urogenital region of females much folded with many fleshy processes.

Color in alcohol. Body ground color light, almost white. Sides with five dark brown bars. First bar under first to fourth spines of second dorsal fin, second under sixth to ninth spines of second dorsal fin, third under posterior half of interdorsal space, fourth under fourth or fifth to seventh or eighth rays of third dorsal fin, last covering posterior third to half of caudal peduncle. Anterior three bars extend ventrally slightly below level of notched lateral line; fourth bar may reach anal-fin base or may end one or two scales above it. Caudal peduncular bar complete and usually widest medially with anterior margin curved to straight. Melanophores between lateral bars and on nape, aligned so as to outline scales. Interspaces between last four bars with melanophores concentrated in narrow secondary bars, especially posteriorly. No horizontal lines on lower sides. Top of head with two main concentrations of melanophores: one just behind eyes roughly in a diamond-shaped patch of dark brown, and a second along a strip-like arc of brown between orbits; this pattern quite striking in some, but obscured with additional pigmentation in others. No large black spot on nape. Interorbit, snout, and upper lip lightly dusted with melanophores. Posterior half of first infraorbital and upper lip just in advance of tip of maxilla lightly pigmented to immaculate. Anterior half of first infraorbital densely pigmented in some, but no well-defined bar present. Coloration of lower lip and chin variable from almost immaculate to dusky. Lower jaw with three or four bar-like pigment concentrations in some, first two extending across chin. Branchiostegal membrane clear, or with a few black dots laterally. Nasal cirrus lightly spotted; supraorbital cirrus densely spotted with black. Lower cheek with a brown bar, which begins beneath pupil and runs down and posterior to rear corner of mouth. A light, diffuse mark just dorsal to cheek bar. Dark brown spot on last infraorbital and a dark brown spot on middle third of preopercular margin. Remainder of cheek with black spots marginally and some clear areas centrally. Opercle lightly spotted with black superficially, and with a deeper brown circular botch on central third. Pectoral-fin base with irregular brown blotches. Pectoral-fin rays with three to five broad, ill-defined brown bars. Pelvic fins clear. Belly white or with some dark brown spots. Membrane of first dorsal fin blotchy posterior to first two spines, with irregular light and dark areas; clear posterior to third spine. Membrane of second dorsal fin lightly spotted; spots tending to line up as faint oblique bars. Spines of second dorsal fin banded with brown. Three black dots along second dorsal-fin base: first dot between second and third spines, second between sixth and seventh spines, third between eight and ninth spines. Third dorsal fin lightly and rather evenly dusted with melanophores. Anal fin evenly and lightly spotted with melanophores. In some specimens, anal fin appears barred when folded. Caudal fin of most males black basally, then with a narrow light zone, followed by a black area covering posterior two-thirds. Light area variable in size; width may be one-third of the caudal-fin length. Caudal fin of females basically light, either with three or four narrow brown bars or with brown reticulations.

Color in life (from photograph, Fig. 4 ). Live specimens similar to preserved specimens except that most dark colors more brown than black, white areas more vibrant and other areas tinged with yellow. Fine melanophores and yellow outlining lateral body scales especially evident. Lateral bars on body tinged with yellow. Iris with radiating yellow-orange lines. Two subocular bars: one angled forward to middle of jaw; second, more prominent, vertical, angled toward posterior tip of jaw.

Comparisons. Within the eastern Pacific species of Enneanectes , E. macrops is most similar to E. reticulatus , but the two can be distinguished by several features. First, they differ in cheek squamation. Although there is considerably variation in E. reticulatus , that species typically has some scales on the cheek while scales are always absent from the cheek of E. macrops . Second, in E. reticulatus the first scale above the lateral line is much larger than the scale above it, and there is an enlarged scale in the pectoral axil; in E. macrops the first two scales above the lateral line are the same size, as are the scales in the pectoral axil. Third, the snout of E. macrops is longer, flatter, and less blunt in outline, the eye is larger, and the head bars are not as well developed. Finally, E. reticulatus has a series of narrow lines of pigmentation on the body above the anal fin that are lacking in E. macrops . Among the western Atlantic Enneanectes species, E. macrops most closely resembles E. boehlkei and E. atrorus in lacking enlarged scales above the lateral line and none (or few) scales on the belly. It differs from those species in growing to a larger body size and having the central rays of the second dorsal fin branched (Rosenblatt 1959).

Range. Coastal eastern Pacific Ocean from Mazatlán, Sinaloa, southward to Acapulo, Guerrero, Mexico, including Islas Tres Marias.

Etymology. From the Greek macros, long, and ops, eye, in reference to the comparatively large eye of this species.

Figures

FIGURE 3. Holotype of Enneanectes macrops sp. nov. (SIO 11 - 394, 36.6 mm SL).

FIGURE 4. Color photograph of Enneanectes macrops sp. nov. (photograph by D. R. Robertson).