Variation in External Morphology of the Glans Penis of Australian Native Rodents

Abstract

In a scanning electron microscopical study of the surface of the glans penis from some Australian rodents, it was found that most species had a long, thick structure with small dorsally projecting spines. In Pseudomys apodemoides, P. delicatulus and P. novaehollandiae the glans was smaller and thinner, with longer spines, and had a prominent bacular mound. The most divergent penes were found in Notomys alexis, N. fuscus and N. mitchelli, in which the glans was small, with very large spines, and tapered to a narrow tip. By contrast, in N. cervinus and N. longicaudatus the glans was more cylindrical and had a prominent bacular mound. The possible significance of these findings is discussed.