PROC. BIOL. SOC. WASH. 107(1), 1994, pp. 90-96 CREAGRUTUS MELASMA, A NEW SPECIES OF CHARACID FISH (TELEOSTEI: CHARACIFORMES) FROM UPLAND STREAMS OF NORTHERN VENEZUELA Richard P. Vari, Antony S. Harold, and Donald C. Taphom Abstract. — Creagrutus melasma, new species, occurs in a band across the northern headwaters of the Rio Orinoco from Tachira state in the west to Monagas in the east. The species is also known from several Caribbean versant drainages, including the Rios Tuy and Neveri. This small-bodied species, which barely exceeds 40 mm SL, is distinguished from congeners by its dorsal-fin and humeral pigmentation as well as a combination of meristic characters. Resumen.—Se describe una nueva especie de Creagrutus que habita una franja en el piedmonte norte de las cuencas altas afluentes del Rio Orinoco desde el estado Tachira en el oeste hasta Monagas en el este. La especie es tambien conocida desde varias cuencas del Mar Caribe, incluyendo los rios Tuy y Neveri. Esta especie tiene un cuerpo pequeiio que raramente excede los 40 mm de longitud estandar. Se distingue de sus congeneres por la pigmentacion en la aleta dorsal, la forma de la mancha humeral, y la combinacion de varias caracteres meristicas. The presence of Creagrutus Giinther in Lago de Valencia and adjoining drainages of northern Venezuela was first noted by Eigenmann (1920:12). Eigenmann, fol-lowed by Pearse (1920: 11), identified these populations as C beni, a species described by Eigenmann (1911:172) from the Rio Beni, northeastern Bolivia. Although Eigen-mann ( 1 920: 1 2) noted the darkly pigmented dorsal fin in material from Lago de Valencia and the Rio Bue, a feature absent in C. beni, he considered the pigmentation a juvenile condition. The absence of such pigmenta-tion in juveniles from elsewhere in the range of C beni (see Eigenmann 1927:421-423) was not discussed. The Lago de Valencia Creagrutus popu-lations with dark dorsal-fin pigmentation, described herein as C melasma, were in-dependently recognized as distinct from all congeners by two of the authors (RPV & ASH) during their revisionary study of the genus and by the third author (DCT) in the course of research on fishes of the Rio Apure basin (Taphom 1992:173-175). The ongo-ing review of Creagrutus by the first two authors indicates that the new species has distinctive derived pigmentation patterns of the dorsal fin and humeral mark and is fur-ther separable from congeners on the basis of a combination of various meristic and morphometric characters. It is broadly dis-tributed in northern headwaters of the Rio Orinoco and several Caribbean drainage ba-sins, being particularly common in the Lago de Valencia basin and northern headwaters of the Rio Apure. It is described herein to make its name available for an ongoing phy-logenetic study (RPV & ASH) of Creagrutus and putatively related taxa. Materials and methods.— Specimens are deposited in the following collections: Academy of Natural Sciences of Philadel-phia (ANSP); California Academy of Sci-ences (CAS), including former Indiana Uni-versity collections (lU); Illinois Natural
BioStor
