Pseudopataecus Johnson 2004, n.gen.

Type species. Pseudopataecus taenianotus n.sp.

Diagnosis. Dorsal fin XIII–XV, 14–15; anal fin I, 11–13; pectoral fin 11; pelvic fin I, 3; all fin rays unbranched. Dorsal fin high, with membrane not or only slightly incised, anterior portion distinctly raised, originating on cranium almost one eye diameter before anterior margin of eye. Pelvic fins long and slender, reaching about two-thirds distance to anus. Head and body highly compressed, body width 6.4–6.9 in SL; frontal bone with non-prominent laterally-bowed ridges, a shallow fleshy depression in their interspace; fleshy cirri densely arranged on margin and ventral surface of mandible; anterior tip of isthmus free; modified scales densely arranged on head and body; bands of minute villiform teeth in jaws and on vomer; no teeth on palatines; vertebrae 30.

Discussion. Pseudopataecus can readily be distinguished from all other aploactinid fishes in having a combination of high numbers of dorsal-fin rays, anal-fin rays and vertebrae, markedly compressed head and body, welldeveloped velvety scales, and shallow fleshy depression present between the laterally-bowed fleshy frontal ridges (Table 1). It has the dorsal fin inserted far forward (almost one orbital diameter before a vertical from anterior margin of eye) and containing 28 or 29 elements, and 30 vertebrae. Of all known aploactinids, only the monotypic Aploactis Temminck & Schlegel, 1843 and Aploactisoma Castelnau, 1872 have a total of both 28 or more dorsal fin elements and 29 or more vertebrae. Species of the latter are easily distinguished from this genus by their more robust head and body, more prominent and sculptured cranial ridges (interorbital ridges slightly divergent in Aploactis, strongly convergent in Aploactisoma), more posteriorly inserted dorsal fin (above posterior margin of eye in Aploactis, anterior margin of eye or just before in Aploactisoma), much shorter dorsal- and anal-fin rays (longest dorsal- and analfin rays 1.7–2.1 and 2.0– 2.5 in Aploactis, 1.8–2.3 and 2.0– 2.5 in Aploactisoma, versus 1.2–1.4 and 1.6–1.8 in head length respectively in Pseudopataecus), and two versus three pelvic-fin rays. Some species of Erisphex Jordan & Starks, 1904 may have up to 27 dorsal fin elements and 31 vertebrae (Poss, 1999), however members of this genus have a considerably more robust head and body, pungent lachrymal, preopercular and dorsal-fin spines, smooth scaleless skin, and only two pelvic fin rays. The broadly defined Cocotropus Kaup, 1858 is superficially similar to Pseudopataecus, but has parallel interorbital ridges, with no more than a narrow shallow groove within the interspace, 25 or fewer dorsal fin elements including 11 or fewer rays, 11 or fewer anal-fin ray elements, 9–12 lateral-line tubes (versus 13–14), and 28 or fewer vertebrae. The frontal bones of Paraploactis Bleeker, 1865 have prominent ridges diverging posteriorly to form a bony pyriform depression. They are more elaborately sculptured, not covered in skin, and their depression deeper and more angular than in Pseudopataecus. Paraploactis also has no more than 25 dorsal fin elements and 28 vertebrae (Poss & Eschmeyer, 1978). Ptarmus Smith, 1947 shares a notably compressed head and body and forward-placed dorsal-fin insertion, but more closely resembles the tetrarogin scorpaenids, with smooth, ill-defined head ridges, a larger mouth, more prominent snout, pungent lachrymal, preopercular, and dorsal-, anal- and pelvic-fin spines, significantly fewer dorsal-, anal- and pectoral-fin rays, and no scales other than in the lateral line (densely arranged in Pseudopataecus).