Detection of cryptic diversity in lizards (Squamata) from two Biosphere Reserves in Mesoamerica Author Castiglia, Riccardo Dipartimento di Biologia e Biotecnologie ' Charles Darwin', Universita di Roma ' La Sapienza', via A. Borelli 50, CAP 00151, Rome, Italy castiglia@uniroma1.it Author Flores-Villela, Oscar Alberto Museo de Zoologia Fac. de Ciencias, Universidad Nacional Autonoma de Mexico, A. P. 70 - 399, Mexico D. F. 04510, Mexico Author Bezerra, Alexandra M. R. https://orcid.org/0000-0002-7972-5535 Mastozoologia / COZOO, Museu Paraense Emilio Goeldi, Campus de Pesquisa, Av. Perimetral 1901, CEP 66077 - 830, Belem, PA, Brazil Author Gornung, Ekaterina Dipartimento di Biologia e Biotecnologie ' Charles Darwin', Universita di Roma ' La Sapienza', via A. Borelli 50, CAP 00151, Rome, Italy Author Annesi, Flavia Dipartimento di Biologia e Biotecnologie ' Charles Darwin', Universita di Roma ' La Sapienza', via A. Borelli 50, CAP 00151, Rome, Italy Author Munoz-Alonso, Luis Antonio El Colegio de la Frontera Sur. Conservacion de las Biodiversidad. Carretera Panamericana y Periferico Sur s / n. C. P. 29290, San Cristobal de las Casas, Chiapas, Mexico Author Solano, Emanuela Dipartimento di Biologia e Biotecnologie ' Charles Darwin', Universita di Roma ' La Sapienza', via A. Borelli 50, CAP 00151, Rome, Italy text Comparative Cytogenetics 2020 2020-12-22 14 4 613 638 http://dx.doi.org/10.3897/CompCytogen.v14i4.57765 journal article http://dx.doi.org/10.3897/CompCytogen.v14i4.57765 1993-078X-4-613 04B277A57E704E0682C5174C5016B74B 01E70616F49857EF8DF1A970E5672D08 Holcosus undulatus (Wiegmann, 1834) Note. Meza-Lazaro and Nieto-Montes de Oca (2015) , in a molecular phylogenetic study, proposed the elevation of 9 of the 12 H. undulatus subspecies to species rank. However, this change has not been widely accepted by other authors. Therefore, we formally use the previous classification, but we also take in account the results of the Meza-Lazaro and Nieto-Montes de Oca (2015) study. Distribution. The species is distributed along both coasts of Mexico from southern Nayarit to northern Costa Rica Pacific coast) and from southern Tamaulipas to central Nicaragua (Atlantic coast) including the peninsula of Yucatan. Samples. RCMX77 (female*) from La Sepultura, Chiapas, Mexico. DNA taxonomy. The MT-ND2 sequence (556-bp) obtained from the individual from Chiapas has a 99% match to two GenBank sequences of H. undulatus parvus Barbour et Noble, 1915 (KR058051 and KR058063). According to Meza-Lazaro and Nieto-Montes de Oca (2015), this subspecies, distributed in the Pacific coast region of Southern Mexico and Northern Guatemala, should be elevated to species rank. Chromosomes. The specimen analyzed shows a 2n = 50 chromosome number (Fig. 5C ). The karyotype comprises a gradual series of acrocentric chromosomes (26M + 24m), as previously described in Castiglia et al. (2010) for H. undulatus from Chamela, Biological Station (Jalisco). In the genus Holcosus , only H. festivus (Chiapas, Castiglia et al. 2010 ) and H. undulatus (Jalisco, present data) have been karyotyped. In Cnemidophorus , a possible sister group of Holcosus ( Pyron et al. 2013 ), 2n = 50 chromosome complement with one biarmed pair has been reported ( Carvalho et al. 2015 ). Different species of Kentropyx Spix, 1825 and Ameiva show a 2n = 50 all-acrocentric karyotype, similar to the one found in Holcosus ( Carvalho et al. 2015 ). Since these genera span the entire phylogenetic tree of Teiidae , we hypothesize that 2n = 50 all-acrocentric karyotype may represent an ancestral condition. However, to reveal more reliable pattern of chromosomal change, an ancestral state analysis combining karyotype and molecular phylogeny should be made (e.g. Castiglia et al. 2013a ).