Pseudoscopelus aphos Prokofiev & Kukuev, 2005

Family:  Chiasmodontidae (Snaketooth fishes)
Max. size:  14.5 cm SL (male/unsexed)
Environment:  bathypelagic; marine; depth range 940 - 1200 m
Distribution:  Nowthwestern Atlantic: Vvicinity of Angular Rise, 34°N, 50°W.
Diagnosis:  Dorsal spines (total): 10-10; Dorsal soft rays (total): 23-23; Anal spines: 2-2; Anal soft rays: 22-22. Diagnosis: Differs from its congeners in having complete absence of photophores and other luminescent formations (Ref. 56658). Description: D1 VIII; D2 II, 23; A II, 22; P 15 (I, 14); V I 5; C x I, 8 + 7, xi; LL 71; vertebrae about 36 (after prolonged storage in formalin, the bones of the holotype strongly decalcinated and the vertebrae of the anterior half of the vertebral column were poorly discernible). Body elongated, narrowing towards caudal peduncle; greatest body depth about 7.3 times SL. Length of caudal peduncle 1.7 times longer than its least depth. Head of moderate size, about 3.5 times SL. Snout 3.4 times head length (HL), noticeably longer than diameter of a rather small orbit, which is 8.2 times HL. Interorbital space about 3.2 times HL. Mucous pit dumbbell-like, opens outside by 3 pores along its posterior edge, of which the middle pore almost twice as large as marginal pores. The bones of head are solid with skin covering them rather thick. Emargination of anterior tip of snout between symphyseal ends of praemaxilla is narrow and poorly developed; antero-dorsal angles of praemaxillaria only slightly protruding. Posterior end of praemaxillare and maxillare bent at 20° to longitudinal axis of the bone; toothed surfaces of praemaxillaria situated at an angle to horizontal body plane. Jaws are equal in size. Praeoperculum at left side fully hidden in skin, at right side its angular margin just slightly protrudes outside. Opercular lobe is well-developed, upper-posterior edge of operculum without emargination. The tongue is long and without teeth. Gill rakers are like small spines, longer than in other examined species of this genus (Ref. 56658).
IUCN Red List Status: Data deficient (DD); Date assessed: 12 October 2018 Ref. (130435)
Threat to humans:  harmless

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