Reticulate phylogeny: a new tetraploid parthenogenetic whiptail lizard derived from hybridization among four bisexual ancestral species of aspidoscelis (reptilia: squamata: teiidae)

We describe the only known tetraploid parthenogenetic species of amniote that has haploid genomes from four distinct ancestral bisexual (gonochoristic) species. These genomes were brought together through three hybridization events that occurred over a time span of hundreds or thousands of years, the last of which occurred recently in captivity without any experimental manipulation. Inheritance of alleles at seven microsatellite deoxyribonucleic acid loci and DNA sequence data for adenosine deaminase intron 9 in the new tetraploid species confirms its parentage and, together with DNA quantification, demonstrates that tetraploidy and high heterozygosity are maintained parthenogenetically generation after generation. Comparisons of univariate and multivariate variation in scalation between the tetraploids and their parental taxa reveal a strong maternal similarity in morphological characters, with little to no significant differences, suggesting that such tetraploid females may exist in old museum samples misidentified as the maternal ancestor. This research on specimens of known parentage adds support to earlier papers that provide important insights for taxonomic treatment of many parthenogenetic clones of teiid lizards that occur in the Western Hemisphere.