grassy flathead

description

Description. Counts and measurements shown in Table 1. Data for all specimens presented first, followed by holotype condition in parentheses. Head and body subcylindrical, elongate, only slightly depressed. Snout, area anteroventral to eye, interorbit, and occipital and lower half of suborbital regions naked. Snout short, subequal or slightly longer (subequal in holotype) than orbital diameter. Interorbit much narrower than orbital diameter. Upper iris lappet simple, triangular; lower simple, weakly convex. Dorsal and lateral surfaces of head mostly smooth, but with preopercular (2) and opercular spines (2). One supracleithral spine usually present (absent on left side, present on right side). Upper preopercular spine longer than lower, not reaching opercular margin. Small or finger-like interopercular flap usually present (finger-like flap present); margin of interopercle smooth. Maxilla reaching slightly beyond anterior margin of pupil to slightly beyond middle of eye (reaching to middle of eye). Anteromedial portion of upper jaw with moderate to large conical or small caniniform (moderate conical) teeth. Palatine teeth irregularly arranged in two to four (three) rows, tending to

Taxonomic revision of the flathead fish genus Platycephalus Bloch, 1785 (Teleostei: Platycephalidae) from Australia, with description of a new species

diagnosis

Diagnosis. A species of Platycephalus with the following combination of characters: second dorsal- and analfin rays usually 14; interorbital width 3.4 – 7.8 % HL; postorbital length 51.4 – 65.2 % HL; head and body subcylindrical, elongate and only slightly depressed; occipital region naked; dorsal and lateral surfaces of head mostly smooth, with preopercular (2), opercular (2) and supracleithral (1) spines; upper preopercular spine longer than lower; upper jaw without large caniniform teeth; head with two dark brown bands from anterior of snout to posterior margin of opercle on both sides, area between bands whitish-brown, pale brown or brown, area below each band pale brown in specimens 159 mm SL or smaller.

Taxonomic revision of the flathead fish genus Platycephalus Bloch, 1785 (Teleostei: Platycephalidae) from Australia, with description of a new species

discussion

Remarks. Platycephalus laevigatus is easily separable from congeneric species in having the head and body subcylindrical, elongate and only slightly depressed (well depressed in others), occipital region naked (vs. scaled, except in P. chauliodous), dorsal and lateral surfaces of the head mostly smooth, only two distinct preopercular, two opercular and one supracleithral spine [vs. some or many other spines and ridges, including lachrymal and preocular spines (but preocular spine rarely absent in P. chauliodous)] and the upper preopercular spine longer than the lower [vs. lower spine longer than upper, except in some smaller specimens of P. caeruleopunctatus and P. chauliodous (upper spine about equal to or longer than lower)]. Although P. laevigatus and P. chauliodous share several other characters setting them apart from other species, P. laevigatus is further distinguished from P. chauliodous in having the upper jaw without large caniniform teeth (such teeth medially on the anterior part of the upper jaw in the latter). In addition, the head coloration in 159 mm SL or smaller specimens of P. laevigatus is unique, thereby allowing distinction from other members of the genus (Fig.

Taxonomic revision of the flathead fish genus Platycephalus Bloch, 1785 (Teleostei: Platycephalidae) from Australia, with description of a new species

distribution

Distribution. Known from southern Australia, from NSW (31 ° 01 ’ S), across SA, Vic and Tas, to Local Waters, WA (32 ° 03 ’ S), occurring on weed-covered reefs and sea-grass beds in depths from 0.5 to 20 m (e. g., Last et al., 1983; Kuiter, 1993, 1994; Hoese et al., 2006; this study). Size. Maximum length 80.8 cm (Hutchins & Swainston, 1986). The largest specimen examined during this study was 484 mm SL (573 mm TL) (Fig. 1 A, B).

Taxonomic revision of the flathead fish genus Platycephalus Bloch, 1785 (Teleostei: Platycephalidae) from Australia, with description of a new species