Campylomormyrus compressirostris (Pellegrin, 1924)

Translated from original description in Pellegrin (1924), pp. 7-8.

Body depth 4 1/5 times into length, minus the snout and the tail, HL at eye 5 ¼ times. Upper head profile descends in a pronounced curve. Snout is extended into a long tube, strongly laterally compressed, pointed downward and a little forward, its length 1 2/3 times postocular HL, its smallest vertical diameter is contained 5 1/3 times in its own length. Chin bears a conical, fleshy appendage measuring about half the eye diameter. Eye goes 4 1/3 times in snout length, 2 2/3 in postorbital region, about 1 times in the interorbital distance. Mouth is particularly small, with 3 teeth above, 4 below. 90 scales along lateral line, 18 / 20 in transverse line, 16 / 17 between dorsal and anal origins, 16 around caudal penduncle. Dorsal with 30 rays, beginning above 10^th anal ray; its base contained 1 ¾ times in the distance which separates it from the head. Anal with 36 rays, a little closer to the caudal origin than to that of the ventral. Pectoral obtusely pointed, extending to the middle of the latter. Caudal peduncle is 4 times as long as deep. Caudal, scaled at its base, has long and pointed lobes.

Color is olive brown on the back, yellowish and lighter on the sides and below. Indistinct traces of a large black bar between the dorsal and anal origins. The fins are grayish.

D. 30; A. 36; P. 12; V. 6; Sq. 18/19/20

A specimen from Boma (mouth of Congo) (Dr. Schouteden). Total Length: 165 +25 = 190 mm.

This Gnathonemus with compressed snout is somewhat close to Gnathonemus rhynchophorus Boulenger, also from Congo, but differs by its more elongate body, shorter snout, more reduced chin appendage, its narrower caudal peduncle, and fewer scales along the lateral line.

The G. Christyi Boulenger, of Leopoldville, is easily distinguished from the species described here by the number of scales around the caudal peduncle (12 instead of 16).

Dorsal spines (total): 0; Dorsal soft rays (total): 30; Analspines: 0; Analsoft rays: 36

Diagnosis: This species is different from Campylomormyrus rhynchophorus based on the following combination of characters: body more elongated, shorter snout, less developed mental lobe, fine caudal peduncle and less scales on the lateral line (Ref. 42477). It differs from Campylomormyrus christyi by more circumpeduncular scales, 16 vs. 12 (Ref. 42477).Description: Body depth 4.2 times in its length, without snout and caudal fin; head length 5.25 times in its length (Ref. 42477). Dorsal head profile clearly convex (Ref. 42477). Snout elongated, forming a long tube, laterally strongly compressed; its direction downward and slightly forward; its length 1.33 times in postocular length; its smallest diameter 5.33 times in its length (Ref. 42477). Mental lobe fleshy, conical, its length about half the eye diameter (Ref. 42477). Eye diameter 4.33 times snout length, 2.66 times in postocular length and about the same length of interorbital width (Ref. 42477). Mouth is very small; upper jaw with 3 conical teeth; lower jaw with 4 conical teeth (Ref. 42477). Caudal peduncle length 4 times its height (Ref. 42477). About 90 scales on the lateral line; 18/20 transversal scales; 16/17 scales between dorsal-fin origin and anal-fin origin; 16 circumpeduncular scales (Ref. 42477). Dorsal fin with 30 rays, anal fin with 36 rays (Ref. 42477).Colouration: Body is olive-brown on back, yellowish and more pale on flanks and ventral side (Ref. 42477). There are vague traces of a large black band between the origin of the dorsal fin and the origin of the anal fin (Ref 42477). Fins are greyish (Ref. 42477).