Chromosomal Heteromorphism in Some Male Lizards of the Genus Anolis

Abstract

Two distantly related species groups in the lizard genus Anolis have evolved a complex form of male chromosomal heteromorphism. At kiakinesis there are 14 valents, 13 bivalents and 1 sex trivalent. Male diploid number is 29. There are 13 pairs of chromosomes, and an unpaired metacentric (Y), unparied acrocentric (X1) and unpaired microchromosome (X2). Females have a diploid number of 30. Their sex chromosomes are X1X1X2X2. Other species of Anolis fail to show chromosomal heteromorphism. These are characterized by a diploid number of 36 in both males and females. A more typical X-Y heteromorphism also appears to be present in the genus. In A. conspersus males, the diploid number is 30. Fourteen pairs are evident but 2 chromosomes, a metacentric and an acrocentric are unpaired. In this species a female was not studied.