| Data on new specimens of the rare subterranean catfish Phreatobius cisternarum are reported. Specimens were collected from hand-dug wells in the region of the mouth of the Amazon river, Brazil. A revised diagnosis of Phreatobius is proposed, and P. cisternarum is redescribed on the basis of new and previously available material. Included are data on coloration, both in life and preserved, SEM observations of external morphology, morphometric and meristic data. One juvenile specimen, the first known of the species, is reported and illustrated. The new and previously available material reveal considerable intraspecific variation in several morphological traits of P. cisternarum. Despite its rarity in collections, P. cisternarum seems to be common in wells in... |
