Arrowhead Batfish

description

Description. Morphometric and meristic values are provided in Tables 1. Body depressed, disc markedly triangular in dorsal view, cranium elevated above surface of other parts of disc; caudal peduncle cylindrical, tapering posteriorly, ventral surface slightly flattened; rostral small and blunt, directed rather more upward than forward (Fig. 5 B), its length much less than half of eye diameter; eye median in size (14.3 – 17.5 % SL, mean = 15.8 % SL), directed dorsolaterally; no pupillary operculum; interorbital space relatively narrow (4.3 – 7.0 % SL, mean = 5.4 % SL), slightly concave, forming a groove between frontals (Fig. 5 A); illicial cavity a small triangular cave, its width equal to its height; esca a single medial bulb bearing two small cirri on dorsal margin; mouth small, terminal; small villiform teeth on jaws forming narrow bands, those on ceratobranchial V forming two large, closely spaced and elongated patches, and quadrangular tooth patches on vomer and palatines. Scales on body surface in the form of relatively blunt bucklers (Figs. 4 A, 5 A – B), few in number, mostly associated with lateral line, skeleton and body margins; a few small bucklers may be present betwee

Revision of batfishes (Lophiiformes: Ogcocephalidae) of New Zealand and adjacent waters, with description of two new species of the genus Malthopsis

description

Non-type: NMNZ P. 027540 (1, 39.4, in poor condition), N. O. Alis, Beryx 2 stn. 2, 24 ° 53 ’ S, 168 ° 22.3 ’ E, ' Seamount B', northern Norfolk Ridge, south of New Caledonia, 23 Oct 1991, coll. C. D. Roberts.

Revision of batfishes (Lophiiformes: Ogcocephalidae) of New Zealand and adjacent waters, with description of two new species of the genus Malthopsis

diagnosis

Diagnosis. A member of Malthopsis with a fully naked ventral surface and interspaces of principal bucklers on dorsal surface lacking dermal spinules. It is distinguished from congeners by having 5 – 6 (mainly 6) dorsal-fin rays; 13 pectoral-fin rays; the subopercular buckler blunt, with a stout anterior-directed spinelet usually present; rostral spine directed rather more upward than forward; relatively few and loosely arranged bucklers; all bucklers blunt; appressed anal fin reaches caudal fin base. In addition, it is the smallest species of the genus reaching 51.1 mm SL in adults.

Revision of batfishes (Lophiiformes: Ogcocephalidae) of New Zealand and adjacent waters, with description of two new species of the genus Malthopsis

discussion

Remarks. Malthopsis parva sp. nov. is most similar to M. jordani in having ventral surface usually naked, but different in having the rostral spine directed upward and forward (vs. nearly upward vertically); a relatively large eye (14.3 – 17.5 % SL vs. 12.5 – 14.9 %); an anterior-directed spine on subopercular buckler usually present. It is also similar to M. annulifera but different in having the rostral spine directed rather upward (vs. nearly forward horizontally); bucklers usually absent from abdomen (vs. usually present), no rings on dorsal surface (present and up to 20 in number), and a relatively small adult body size.

Revision of batfishes (Lophiiformes: Ogcocephalidae) of New Zealand and adjacent waters, with description of two new species of the genus Malthopsis