Xiphophorus-Hybriden aus Nord-Mexiko, mit einer Revision der Taxa X. kosszanderi und X. roseni (Osteichthyes, Poeciliidae)

" The genus Xiphophorus HECKEL, 1848 was recently revised by Rosen (1979) and made some important changes, and with the discovery of new Xiphophorus taxa it was extended (MEYER & SCHARTL, 1980; MEYER & WISCHNATH, 1981). The present work should split off the genus of natural hybrids, namely kosszanderi and roseni. Rose4n (1979) reported for the first time a Xiphophorus natural hybrid from the Rio Usumacinta system (Guatemala), X. alvarezi x helleri. As a result, three Xiphophorus natural hybrid populations from Northern Mexico are presented "