Stomatorhinus patrizii Vinciguerra, 1928
Species overview
Very small fish, body moderately short, rather deep, head slightly shorter than or as long as body depth, longer than its depth, snout rounded or truncate, slightly protruding mouth which is slightly subterminal; caudal peduncle slim. Brown, whitish dotted on head and neck. Size observed: 61 mm SL, 72 mm TL.
S. patrizii(measurements)
Taxonomic description
-Body moderately short, laterally compressed, body depth 28-33 % SL, greatest depth between pelvic and anal fin.
-Head length 27-31 % SL; head depth 22-26 % SL, 72-86 % body depth.
-Outline of back rather straight, upper profile of head convex, underside of head concave, outline of belly slightly convex.
-Snout truncate to rounded, 14-20 % head length, 24-35 % postorbital length.
-Mouth width 13-19 % head length, slightly subterminal, its edge below anterior rim of the eye, upper jaw on a level with lower edge base of pectoral fin.
-Chin inconspicuous.
-Teeth notched, 6-7/7-8.
-Nostrils clearly separate, both oval, anterior nostril on a level with centre of eye, posterior nostril close to edge of mouth.
-Eye diameter 14-17 % head length, 23-30 % postorbital length.
-Opercular cleft curved 24-32 % head length, 30-38 % head depth.
-Dorsal fin 15-16 fin-rays, base of D 20-24 % SL, anal fin 18-21 rays, base of A 22-28 % SL, origin of D behind origin of A, end of D more or less opposite end of A; predorsal length 59-65 % SL, preanal length 54-59 % SL.
-Pectoral fin pointed, extending more or less to tip of pelvic fin or even beyond. V is closer to P than to A.
-Caudal fin obtusely pointed, the scaled lobes short and rounded, about 1/5 the length of the fin. 44-48 scales in lateral line, only 32-40 with pores; 14 scales round caudal peduncle.
-Caudal peduncle 16-21 % SL, its depth 4-6 % SL, 23-35 % its length.
-Coloration »Uniform chestnut-brown with some whitish dots on head and anterior part of back«. Preserved specimens without the electroreceptor epidermis show numerous small dark spots on head and belly.
The white dots on head and back are the site of sensory organs, mostly electroreceptors, but they might be free neuromasts, mechanoreceptors, or true lateral line organs. Which of them, shown here, belong into which category cannot be decided on a picture.
Type locality
»Buta«. (2° 48 ‘ N 24° 44 ‘ E) Haut-Zaïre, district of Democratic Republic of Congo.
Distribution
Congo basin (Uélé and Yangambi)« (Uele river: 4° 09 ‘ N 22° 26 ‘ E; Yangambi: 0° 47 ‘ N 24° 28 ‘ E.) Democratic Republic of Congo.