Alabes obtusirostris, Hutchins & Morrison, 2004

Hutchin, Barry & Morrison, Sue, 2004, Five New Fish Species of the Genus Alabes (Gobiesocidae: Cheilobranchinae), Records of the Australian Museum 56 (2), pp. 147-158 : 152

Alabes obtusirostris n.sp

Fig. 1 ; Tables 1, 4

Type material. HOLOTYPE: CSIRO H.4462-01, 46 mm SL, Victoria, east of Lakes Entrance (between 37°52.8'S 148°11.8'E and 37°51.7'S 148°13.8'E), benthic sled at 28 m, FRV Southern Surveyor , 24 November 1996 . PARATYPE: AMS I.37755-001, 21 mm SL, Western Australia, east of Binningup (33°09'S 114°49'E), depth 65 m , CSIRO, 10 August 1962 (field number G3/176/62) .

Diagnosis. The diagnostic characters of Alabes obtusirostris are listed in Table 1. It differs from all other species of Alabes by a combination of its moderately large gill opening (3.1– 4.3 in HL), lack of a pelvic-fin rudiment, absence of all cephalic pores in the lateral-line system, and its large number (40) of epineural ribs. It possesses a short, blunt head with wide lips (giving it a rather pugnacious appearance), and short dorsal and anal fins.

Description. Measurements of the holotype and paratypes are presented in Table 4. Body almost cylindrical, reaching a maximum depth about middle of body, then tapering posteriorly, body depth 13.6 (17.6) in SL, maximum body width (= width at level of gill slit) 14.3 (19.2) in SL; head rounded to somewhat blunt anteriorly, a little wider than body (head width 1.6 [1.9] in HL), HL 8.4(8.5) in SL; snout rather truncate in dorsal view, length 4.6 (4.1) in HL; diameter of orbit 4.8 (3.8) in HL, noticeably greater than bony interorbital width (6.9 [10.3] in HL); lateral-line sensory system lacking cephalic pores; gill opening a moderately narrow slit, length 3.1 (4.3) in HL; mouth terminal or lower jaw slightly projecting over upper jaw, upper and lower lips both fleshy and wide, producing a somewhat pugnacious appearance, rear corner of mouth reaching almost to below anterior margin of eye (pigmented area); teeth in holotype worn and more incisorform, those of paratype smaller, conical, caninelike, 1 row in upper and lower jaws; caudal fin with 8 fin rays; bases of dorsal and anal fins relatively short, insertion of dorsal fin well posterior to vertical through urogenital opening (snout to insertion 1.7 [2.0], snout to urogenital opening 2.5, both in SL); anal fin very short, insertion almost at caudal fin (snout to insertion 1.2 [1.1]in SL); total vertebrae could not be counted for holotype but cleared and stained paratype has a total of 70 vertebra (23 precaudal), with last epineural on 40th vertebra.

Preserved coloration (in alcohol). Head and body overall pale brown, fins more translucent; very faint indication of 3–5 reddish crossbands or blotches on body, more obvious on lower half of body.

Live coloration. Unknown but bands described above could have been blackish (see colour description of A. scotti n.sp. below).

Distribution. Alabes obtusirostris is known from only two locations: off Lakes Entrance in Victoria and off Binningup in southwestern Western Australia.

Remarks. This species has only been collected from coastal waters at depths between 28 and 65 m. Like Alabes scotti (described below), it appears to inhabit sandy bottoms. However, morphologically, it has more in common with A. dorsalis and A. elongata (described above); its body anteriorly is rather cylindrical in cross-section and it possesses a large gill opening, but it lacks the prominent rudimentary pelvic fin that characterizes the latter two species. This species is named obtusirostris with reference to its blunt snout.

Figures

Fig. 1. Alabes obtusirostris. Holotype, CSIRO H.4462-01, 46 mm SL, Lakes Entrance, Victoria (drawn by S. Morrison).