Chromosomes of Bipes, Mesobaena, and other amphisbaenians (Reptilia), with comments on their evolution. American Museum novitates ; no. 2869

Abstract

"Karyotypes of three amphisbaenians (Bipes tridactylus, the monotypic Mesobaena, and Amphisbaena gonavensis) are presented for the first time. The karyotypes of all three species of Bipes are compared, using new material for each species, and all published karyotypes for representatives of the Amphisbaenia (approximately 20% of the Recent species, worldwide) are reviewed. Diploid chromosome numbers vary from 25 to 50, and centric fission of macrochromosomes appears to have been a major type of karyotypic evolution in these animals. Bipes tridactylus is the only amphisbaenian known to have recognizable sex chromosomes, with a ZZ([male]):ZW([female]) system (female heterogamety)"--P. [1].