Breeding, Larval Morphology and Experimental Hybridization of Taiwanese Brown Frogs, Rana longicrus and R. sauteri

Abstract

Two endemic brown frogs, R. longicrus and R. sauteri, occur in Taiwan. R. longicrus lives in northern lowlands and breeds in still water during Dec. and Jan. Its tadpole is of a generalized type. R. sauteri lives in the central mountainous regions and breeds in streams and ponds from Oct.-April. It lays fewer and larger eggs than does R. longicrus. Its tadpole has a large abdominal sucker with which it clings to rocks in streams. Almost all artificial hybrids between female R. longicrus and male R. sauteri died at gastrula or neurula stages; only a few survived to late larval stages. All of the hybrids between female R. sauteri and male R. longicrus died as early gastrulae. R. sauteri is unique among the brown frogs in its larval morphology and habitats, and these characters suggest some relationship to the genus Amolops.