Enneanectes glendae, 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 : 362-366

Enneanectes glendae sp. nov.

“Slender triplefin”

( Figs. 1 & 2 )

Enneanectes “species C”: Robertson & Allen 2008, Erisman et al. 2011.

A total of 228 specimens from 16 collections, all from Pacific waters of Mexico.

Holotype. SIO 11-394 (formerly UCLA 58-10), 26.8 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. Nayarit: SIO 11-394, 6 specimens (14.6–26.4 mm SL), Ensenada Chacala, collected with the holotype; SIO 11-393 (formerly UCLA 58-5), 9 (12.8–22.4), Ensenada Chacala, S. edge of small point inside Punta Chacala, below village of Chacala; SIO 70-167, Nayarit, Bahia Chamela, 40 (25–30.5); CAS 235202, same as SIO 70-167, 2 (27–30); LACM 58001-1, same as SIO 70-167, 2 (28–29); USNM 410090, same as SIO 70-167, 2 (27–30). Islas Marías: SIO 62-19-61B, Isla María Madre, 5 (23–27); SIO 62-20-61E, Isla María Madre, 2 (24–25); SIO 10-134, Isla María Cleofas, 5(23–24); SIO 62-55-61L, Isla María Cleofas, 51 (12.5–27); SIO 10-142, Isla San Juanito, 4(15–22.5). Jalisco: SIO 01-182, Puerto Vallarta, 54 (12–29); SIO 70-169, Bahia Banderas, 7 (25–30); SIO 70-163, Bahia Navidad, 7 (25–30); UW 151893, same as SIO 70-163, 1 (28). Colima: SIO 70-158, Manzanillo, 12 (23–26.5). Guerrero: SIO 70-155, White Friars, 13 (25.5–29.5).

Additional material. SIO 10-139, Islas Marías, Isla María Madre, 2 (15.5–17); SIO 10-151, Islas Marías, Isla San Juanito, 1(15.5); SIO 10-150, Isla San Juanito, 9 (14–19).

Diagnosis. A slender-bodied species of Enneanectes with a large eye, no scales on opercle, 34–36 longitudinal scale rows, 19–20 segmented anal-fin rays, no dorsal soft rays branched at tip, females weakly barred and breeding males almost black.

Description. First dorsal fin with three spines; second dorsal fin with 12–15 (13.8) spines; third dorsal fin with 8–10 (9) segmented rays. Anal fin with two spines and 19–20 (19.2) segmented rays. Pectoral fin with 15–17 (16) rays; central rays branched with upper 1–2 and lower 7–8 unbranched. Lateral line discontinuous with 16–17 (16.9) pored scales in upper portion and 20–23 (21.1) notched scales in lower portion. Lateral scale rows 34–36 (34.9); scales above pored lateral line 2 or 2 ½; scales below pored lateral line 5.

Measurements of 16 specimens expressed as thousands of SL (means in parentheses). Head length 284–311 (299); postorbital length 126–149 (137); head depth 170–194 (183); head width 186–211 (197); snout length 85–104 (95); upper jaw length 99–116 (109); eye diameter 98–116 (106); first dorsal spine length 131–147 (138); second dorsal spine length 116–141 (127); third dorsal spine length 95–116 (106); length of third spine of second dorsal fin 180–205 (188); length of third ray of third dorsal fin 151–181 (167); length of second dorsal-fin base 295–338 (317); length of third dorsal-fin base 146–174 (162); length of anal-fin base 408–450 (434); distance from pelvic-fin insertion to anal-fin insertion 241–277 (263); pectoral-fin length 288–360 (320); pelvic-fin length 243–304 (256); caudal peduncle length 146–184 (159); caudal peduncle depth 84–96 (89).

Body slender, relatively elongate; dorsal and ventral outlines almost straight. Head narrowly triangular when viewed from above; outline from opercle to snout slightly convex and slightly constricted under orbits. Snout slightly pointed in lateral view, but not elongate. Profile gently convex between upper lip and orbit, then flat posteriorly to dorsal-fin origin.

Eye large and prominent, placed high on head. Maxilla extending posteriorly to level just under middle of eye. Jaws subequal; lower jaw slightly included in upper. Preopercle free from opercle except for upper one-third of vertical limb. Vertical limb of preopercle inclined posteriorly, gently sloping into horizontal limb. Margin of opercular bone evenly rounded and smooth. Top of head covered with closely set, short slender spinules. Dorsal margin of orbit with a row of spinules extending from level of upper edge of opercle forward to level of posterior nostril; remainder of interorbital margin smooth. Posterior margin of supratemporal canal of cephalic sensory system spinulose. Upper margin of opercle smooth or with a few feeble spines.

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 and closely set, in three irregular V-shaped rows. No teeth on palatine.

Eye with a small, narrowly triangular supraorbital cirrus, set on posterior edge of upper margin, its length less than or equal to interorbital width. Anterior nostril with a short tube surmounted by a simple cirrus, its length about equal to interspace between nostrils. Posterior nostril elliptical, without a tube or cirrus, its opening about twice as large as opening of anterior nostril.

Head pores in double rows on margin of preopercle, infraorbitals and lower jaw. A single median pit on chin, just posterior to symphysis. Two enlarged pores at anterior end of first infraorbital, and two small pores just above upper lip, one at end of each nasal bone. A pair of small interorbital pores, just behind level of posterior nostrils.

First dorsal-fin spine inserted just behind level of mid-opercle. First two spines subequal and set close together; third spine more widely spaced and shorter. Membrane between spines shallowly incised. Membrane between spinous dorsal fins deeply incised. Outline of second dorsal fin more or less even; first spine about two-thirds as long as longest, second to seventh or eighth similar in length, with more posterior spines decreasing in length; last spine about one-fourth length of third spine. Interspace between second and third dorsal fins two or three scales wide. First to fourth rays of third dorsal fin about equal in length; succeeding rays decreasing in length; last ray just less than one-half length of third ray. All dorsal-fin rays unbranched. Anal-fin spines set close together; first about two-thirds as long as second, which is about one-half as long as first anal-fin segmented ray. Outline of anal-fin even with anterior rays somewhat shorter than posterior rays. Antepenultimate ray longest, longer than first ray by one-third. Longest ray, when depressed, falls two scales short of caudal-fin base. Anal-fin membrane shallowly incised, distal one-fourth of anterior margin of each ray free. Pectoral fin extending to a point under last third of second dorsal fin. Pectoral-fin formula variable. In specimens larger than 20 mm SL, upper two to four rays unbranched, succeeding five to seven rays branched, and lower seven or eight rays unbranched. In specimens less than 20 mm SL, a greater number of rays are unbranched. Pectoral fin pointed in outline; upper margin of fin almost flat, lower margin considerably more rounded; lower unbranched rays thickened. Pelvic fin long, inner ray extending to or almost to anal-fin origin; outer ray about two-thirds as long as inner ray.

Sides completely scaled. Belly and pectoral-fin base naked. No scales on cheek or opercle. Five or six cycloid scales on base of caudal-fin rays. Pored portion of lateral line ending under penultimate dorsal-fin spine. Notched portion of lateral line commencing one to three scales before end of pored lateral line and two scale rows below it.

Genital papilla of males short, conical, surmounted by two thin tentacles. Urogenital region of females much folded with many fleshy processes.

Color of males in alcohol. Body posterior to second dorsal fin dark, almost black. A band under third dorsalfin slightly lighter. Dark coloration extends forward on lower sides below pored lateral line. Above lateral line body ground color light, with the scales outlined in dark brown by a line passing through outer third of each scale. Pectoral-fin base dark. Lower portion of head dark; head above midline lighter, with scattered melanophores. Snout, underparts of head, and belly light with dark punctulations. Pectoral fins clear, spotted with rather evenly spaced melanophores; spots densest basally and ventrally. Pelvic fins lightly dusted with black. Dorsal-fin rays outlined in black; fin membrane clear, or lightly dusted with melanophores; first dorsal fin darkest. Anal fin dusky. Caudal fin dusky, with basal and distal third darker. Juvenile males similar in coloration to females.

Color of females in alcohol. Body ground color light. Upper sides with three ill-defined dusky bars; first extending from end of first dorsal fin posteriorly to about fourth spine of second dorsal fin, second under middle third of second dorsal fin, and last extending from posterior end of second dorsal fin to middle of third dorsal fin. Caudal peduncle black. Variable number of olive spots outlined in black present along lateral midline. Head generally light, with dusky areas similar to dark areas in males. Belly and underside of head immaculate. Pectoral fin similar to, but lighter than, in males. Pelvic fins clear. First dorsal fin dark; second and third dorsal fins clear. Anal fin evenly and lightly dusted with melanophores. Caudal fin dark distally.

Color in life. The following description is paraphrased from field notes by Boyd W. Walker, based on the holotype and the largest paratype from the same collection, after they had been in formalin for four hours: general color black on lower three-fourths of head and body except for an olive-green bar under posterior one-third of third dorsal fin. Upper one-fourth flushed with red and with brick-red bars. A spot of brick-red over upper anterior margin of eye and one on posterior one-third of eye. First dorsal fin yellow with some brick-red overwash. Second and third dorsal fins clear, with faint, narrow brick-red bars. Anal fin almost black. Caudal fin dark distally, fading at base to olive-yellow, sometimes darker.

Color from photographs ( Fig. 2 ). Males are general very dark compared to females: ground color light with dense concentrations of melanophores, especially on the lateral body. Body mostly covered with dense melanophores with lighter areas (corresponding to those in females) under the anterior and posterior portions of the second dorsal fin, under the posterior portion of the third dorsal fin. Lateral line scales outlined with melanophores, but obscured in heavily pigmented areas. Dorsum with irregular blotches of pale red and yellow, somewhat obscured by melanophores. Caudal peduncle completely covered by a dark saddle, with a light notch at midline of its posterior margin. Caudal fin white proximally, with a dusting of melanophores on distal half. Head with black smudge on opercle, an indistinct subocular bar extending toward tip of snout, a faint spot of melanophores under eye, and pale reddish blotches on nape. First dorsal fin yellow-orange, with scattered melanophores mostly along spines. Second and third dorsal fins light. Anal fin and pectoral-fin base with dense melanophores. Females are more colorful than males: ground color light, with most scales outlined by melanophores, and orange saddles and orange and yellow blotches on body; lower body above anal fin with four orange blotches. Caudal peduncle saddle reddish brown anteriorly, grading to black posteriorly, with a light notch at midline of posterior margin, followed posteriorly by a distinct orange bar covering base of caudal fin, a distinct white bar covering proximal half of fin, and a broad, orange bar covering posterior half of fin. Head coloration similar to that of males, but less dark, with a subocular bar extending toward snout, a blotch of melanophores under eye and reddish blotches on nape. First dorsal fin similar to that of males: yellow-orange with melanophores along anterior spines. Second and third dorsal fins light with faint diagonal stripes formed by pigment on spines and rays. Anal fin yellow to yellow-orange posteriorly. Pectoral-fin base with scattered melanophores.

Comparisons. Among the eastern Pacific tripterygiids, Enneanectes glendae is most likely to be confused with the young of Crocodilichthys gracilis , but differs from that species in the lower dorsal- and anal-fin counts, spinose head, larger scales and lack of strong barring on the sides. In addition, the ranges of the two forms probably do not overlap, C. gracilis being restricted to the Gulf of California. It is possible that very young of Lepidonectes would lack scales on the cheeks and opercles and could be confused with E. glendae , but Lepidonectes species have a much longer pored lateral line and a much shorter notched lateral line. Enneanectes glendae is quite distinctive compared to other species of Enneanectes (Rosenblatt 1959) . Its slender body and head, large eye, lack of scales on the opercle, small scales, and simple dorsal-fin rays immediately distinguish it from all other eastern Pacific species of the genus. In addition, breeding males of E. glendae are black, while those of other eastern Pacific Enneanectes species are red ventrally. Similarly, E. glendae differs from all western Atlantic species in the genus in having a relatively slender body and high scale counts.

Range. Known from coastal areas of the eastern Pacific from Ensenada Chacala, Nayarit, Mexico southward to Guerrero and Islas Tres Marias, Mexico.

Etymology. Named in honor of Glenda Rosenblatt, wife of the senior author.

Figures

FIGURE 1. Holotype of Enneanectes glendae sp. nov. (SIO 11 - 394, 26.8 mm SL).

FIGURE 2. Color photographs of male (above) and female (below) of Enneanectes glendae sp. nov. (photographs by D. R. Robertson).