ABSTRACT
Neoscopelids are small to medium in size (<30cm) with a compressed head and body. Jaws are large, extend to the back of the orbit, and bear villiform teeth. An adipose fin is present. The fins are large; the dorsal fin origin lies above the pelvic fin and the anal fin origin is well behind the dorsal fin insertion. The large pectorals extend posteriad to the anus or anal fin origin. The eyes are small (eye diameter >7 times in head length) in Scopelengys and larger (eye diameter 3-5 times in head length) in Neoscopelus. Scopelengys has an elongate body covered with large, highly deciduous cycloid scales, and lacks light organs. Neoscopelus is moderately stout, covered with large cycloid somewhat deciduous scales, and has ventrolateral rows of photophores and a series of light organs on the periphery of the tongue (Figure 1). The bathypelagic Scopelengys is brown to black, weakly ossified, and lacks a gas bladder. In contrast, the benthopelagic Neoscopelus is reddish to dark red on the upper regions of the head and body and silvery below, with pinkish fins; members of the genus are well ossified with firm musculature, and the gas bladder is large and well developed. The two species of Neoscopelus that occur in the region can be distinguished as follows: 1) in N. microchir the lateral series of photophores (LO series) extends posteriad to or beyond a vertical from the anal-fin insertion whereas in N. macrolepidotus the series stops short of the analfin origin; 2) N. microchir has 14-16 total gill rakers whereas N. macrolepidotus has 10-12 (Nafpaktitis 1977; Hulley 1984a, 1986).
