4 NEW SPECIES OF SPINY RATS OF THE GENUS PROECHIMYS (RODENTIA, ECHIMYIDAE) FROM THE WESTERN AMAZON OF BRAZIL

A total of eight species of spiny rats of the genus Proechimys are inc luded within a collection of mammals assembled during a year-long surv ey of vertebrates along the Rio Jurua in the western Amazon Basin of B razil. Four of these are the well-recognized taxa in western Amazonia, P. simonsi, P. brevicauda, P. cuvieri, and P. steerei, but the remain ing four are new (P. echinothrix, P. kulinae, P. pattoni, and P. gardn eri). The diagnoses and descriptions of the new taxa are provided here in on the basis of genetic (chromosomes and DNA sequences) and morphol ogical data. The latter include bacular characters, qualitative and qu antitative features of the cranium and external morphology.