Paired Frontal Foramina in Living Teleosts: Definition of a New Family of Characoid Fishes, the Crenuchidae

Abstract

Crenuchus spilurus Günther¹ (order Cypriniformes) is a small characoid fish, from Guiana and the Amazon basin, possessing a number of unusual features. First, its dentition, most of its skull structures (Fig. 1) and its general appearance would place it near the cheirodonts (including Aphyocharax), and possibly also near Characidium^2,3. But its rather long dorsal fin (about 18 rays) is characteristic for remotely related groups (with the exception of some Characidiidi; see following): the Serrasalminae (piranhas and others) among the Characidae, and only one genus, Hoplias, among the Erythrinidae. All other forms (at least 1,000 species in South America) have 9–13 rays, generally 10–11.