Multiple sex chromosome system and Robertsonian rearrangements involved in the chromosome evolution of the Phymaturus palluma group (Iguania: Liolaemidae)

GROSSO, JIMENA RENEÉ; CARDOZO, DARIO; BALDO, DIEGO; LOBO, FERNANDO

JOURNAL OF HERPETOLOGY

SOC STUDY AMPHIBIANS REPTILES

Lugar: Salt Lake City; Año: 2017

0022-1511

The Liolaemid genus Phymaturus is a clade of saxicolous lizards with 44species recognized, grouped in the P. palluma and the P. patagonicus groups. The chromosome data about this genus are extremely scarce; however unpublished evidence suggests a great karyotypic diversity, mainly in the P. palluma group. In this work, we describe the karyotypes of six species of the P. palluma group (one of them unnamed), and report a multiple chromosome sex determination system with heterogametic males (X1X1X2X2 / X1X2Y). This sex-system represents a putative synapomorphy for the group. In accordance with the literature previously published and the data obtained in this work we report a wide variability for the diploid number of the P. palluma group (2N = 26 to 2N= 36), but same autosomic fundamental number in all the species of the clade (FNa = 32). Such variation is a consequence of different numbers of telocentric macroautosome pairs among karyotypes (2 to 10), which suggest chromosomalevolution of the group, driven mainly by successive Robertsonian rearrangements.