Pseudoscopelus astronesthidens Prokofiev & Kukuev, 2006

Melo, Marcelo R. S., 2019, A revision of the genus Pseudoscopelus Lütken (Chiasmodontidae: Acanthomorphata) with descriptions of three new species 2710, Zootaxa 2710 (1), pp. 1-78 : 55

Pseudoscopelus astronesthidens Prokofiev & Kukuev species group

Composition. The Pseudoscopelus astronesthidens species group is composed of three species: P. astronesthidens , P. australis , and P. odontoglossum .

Diagnosis. The Pseudoscopelus astronesthidens species group is diagnosed from its congeners by the unique photophore and dentition patterns: luminescent tissue present as discrete photophores (vs. completely absent in P. aphos and as vestigial white lines in P. parini ); mxf short, restricted to area below orbit, not connected to apf posteriorly (vs. mxf absent or if present connected to apf posteriorly); elongate canine teeth present on basihyal and second basibranchial (vs. teeth absent on basihyal; small conical teeth present on second basibranchial); palatine teeth type 4, with considerable ability to bend caudally (vs. palatine teeth of type 1, firmly attached to bone).

Ontogenetic changes. Pseudoscopelus australis has a negative, statistically significant allometric growth of the pectoral fin (P<0.05, Fig. 8 C ); because of limited samples available, it could not be determined if this is also true in P. astronesthidens and P. odontoglossum ( Fig. 21 ). Dentition pattern of specimens was formed in specimens as small as 31.9 mm (CAS-SU 66492).

Figures

FIGURE 8. Graphic of the species of Pseudoscopelus which allometric pectoral-fin growth is allometric in relation to the standard length is statistically significant: (A) positive growth (P=0.001) in P. scriptus (blue squares); (B) negative growth (P=0.042) in P. obtusifrons (black triangles); (C) negative growth (P<0.001) in P. australis (red dots)

FIGURE 21. Schematic drawing of the photophore pattern in lateral and ventral vies of (A) Pseudoscopelus scutatus, ISH 567b-c/1966, 80.4 mm, paratype; (B) P. bothrorrhinos, SIO 07-6, 39.6 mm, paratype.