3 p. : 1 ill. ; 24 cm.Includes bibliographical references (p. 3)

Barton, Otis.

La Monte, Francesca Raimonde, b. 1895.

Nichols, John T. (John Treadwell), 1883-1958.

American Museum of Natural History Scientific Publications

AMERICAN MUSEUMNOVITATESPUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORYCITY OF NEW YORK JANUARY 20, 1953 NUMBER 1606A NEW ALESTES AND LITTLE-KNOWNBARB US FROM GABOONBY J. T. NICHOLS AND F. R. LA MONTEMr. Otis Barton has presented the Museum with a few smallfishes he obtained at Mouila, in the Ogowe Valley, Gaboon, inSeptember, 1951.They comprise one specimon each of four species of Alestes, oneof which seems to be undescribed and the other three we identifyas A. chaperi Sauvage, and the young of A. kingsleyi Gunther andA. schoutedeni Boulenger. There are also two specimens of a littleknown form of Barbus guirali Thominot (see beyond). Inciden-tally, Alestes schoutedeni is the only one of these five species rep-resented in the extensive collection of fresh-water fishes of theCongo Basin obtained by the American Museum Congo Expedi-tion of 1909 to 1915.Alestes bartoni, new speciesFigure 1An elongate Alestes (depth 3.4) with 34 scales in the lateral line,5 1/2 rows above it; the dorsal high and pointed, its origin im-mediately behind the base of the ventrals; 21 anal rays; a conspic-uous black blotch at the base of the caudal, and vague darkblotch behind the head at a level of the upper half of the eye.DESCRIPTION OF TYPE: No. 19654, the American Museum ofNatural Nistory, from Mouila, Ogowe Valley, Gaboon, Africa,September, 1951, collected by Otis Barton, our only specimen.Length to base of caudal, 89 mm. Depth in this length, 3.4;head, 3.9. Eye in head, 2.9; snout, 3.4; interorbital, 3.0; maxillary,2.8; greatest width of body, 2.3; depth of peduncle, 2.5; its length,2 AMERICAN MUSEUM NOVITATES NO. 16061.4; pectoral, 1.2; ventral, 1.5; longest anal ray, 2. Head in longestdorsal ray, 1.2.Dorsal, 10; anal, 21. Scales 34, 5 1/2 rows above lateral line.Gill-rakers (lower limb of arch), 12 or 14.Body well compressed, back little elevated, outline very shal-lowly convex from lower jaw to ventrals, thence slanting slightlydownward to anal origin, abruptly upward from anal origin topeduncle. Snout short, blunt, maxillary curving more downwardthan backward, and not reaching to under front margin of eye.FIG. 1. Alestes bartoni, type. Standard length, 89 mm.Dorsal high and pointed, when depressed its tip not reachingadipose by a distance equal to half eye, its origin immediately be-hind the base of ventrals, slightly nearer base of caudal than tip ofsnout. Pectorals reaching five-sixths of the distance to ventrals;ventrals, with a very short filamentous tip, to vent, and five-sixths to anal origin.A conspicuous black blotch covers the middle of the hind end ofpeduncle and base of caudal, extending narrowly back on themiddle caudal rays; there is a vague dark blotch behind the headat a level of the upper half of the eye; and a faint silvery band,dark along its upper margin, extends thence straight backwardonto the peduncle.This fish probably represents Alestes intermedius Boulenger ofSouth Cameroon, in the Ogowe Valley. Its differences therefromare slight, some correlated with being conspicuously longer bodied(as more slender peduncle, fewer scale rows above the lateral line).Its dorsal is high and of similar shape, but placed somewhat1953 ALESTES AND BARBUS 3farther back, and to judge from our single specimen there areslight color differences. It is likely that the half-grown A. interme-dius listed by Boulenger, 1909 (Catalogue of the fresh-waterfishes of Africa, vol. 1, p. 202) from Ogowe, should be referred tothis form.We take pleasure in naming an African fish for Mr. Otis Barton,whose unconquerable spirit of adventure has taken him manyplaces, and who has brought back to the American Museum var-ious new or little-known fishes from diverse parts of the world.Barbus guirali melanepiptera PellegrinTwo specimans of Barbus 57 and 76 mm. long (without caudal)are close to Barbus guirali Thominot, 1886, from Cameroon, butdiffer from his description, and the subsequent ones by Boulengerand by Pappenheim, 1911, of specimens from there, in that thewhole dorsal fin has a broad black margin, not covering merely thefirst three branched rays, though the black margin is somewhatnarrower and less intense posteriorly.Pellegrin published an incomplete description of melanepiptera,as a race of B. camptacanthus, in 1924, from Gaboon (Bull. Soc.Zool. France, vol. 49, p. 288), but in 1930 (Bull. Soc. Zool. France,vol. 55, p. 199) considered it the young of guirali. We are satisfiedthat the above specimens are referable to his melanepiptera, butat least suspect that the same is a valid race of guirali.Both our specimens are males (determined by dissection andsmear-C. Marzullo), and it is possible that the differently coloreddorsal is a sex character.Scales with a few conspicuous radiating striae. Last simple dor-sal ray rather slender, but well ossified and serrate for two-thirdsof its length; two barbels on each side. Scales 22, 12 around caudalpeduncle. Base of ventral entirely below the dorsal. Dorsalbranched rays, 8; anal, 5. Depth in standard length, 2.6 (2.5 in thesmaller); caudal peduncle as long as deep (slightly longer than deepin the smaller). Posterior barbel, 1.6 times eye. Head rather pointed,snout as long as eye. Head in length, 3.5 (3.2 in the smaller).Eye in head, 3.3 (3.2 in the smaller); interorbital, 3. Dorsal baseequidistant between the root of caudal and hind margin of eye(center of eye in the smaller).

Alestes and Barbus

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