The South American lizard genus Liolaemus comprises > 260 species, of which > 60 are recognized as members of the Liolaemus montanus group, distributed throughout the Andes in central Peru, Bolivia, Chile and central Argentina. Despite its great morphological diversity and complex taxonomic history, a robust phylogenetic estimate is still lacking for this group. Here, we study the morphological and molecular diversity of the L. montanus group and present the most complete quantitative phylogenetic hypothesis for the group to date. Our phylogeny includes 103 terminal taxa, of which 91 are members of the L. montanus group (58 are assigned to available species and 33 are of uncertain taxonomic status). Our matrix includes 306 morphological and ecological characters and 3057 molecular characters. Morphological characters include 48 continuous and 258 discrete characters, of which 70% (216) are new to the literature. The molecular characters represent five mitochondrial markers. We performed three analyses: a morphology-only matrix, a molecular-only matrix and a matrix including both morphological and molecular characters (total evidence hypothesis). Our total evidence hypothesis recovered the L. montanus group as monophyletic and included ≥ 12 major clades, revealing an unexpectedly complex phylogeny.

The genus Liolaemus is a group of lizards with more than 230 recognized species, which have been grouped in differentclades and subgroups. One of the monophyletic groups is the one of Liolaemus boulengeri or “the patch group”; this cladeitself is integrated by several monophyletic groups: the groups Liolaemus anomalus, Liolaemus wiegmanii, Liolaemusdarwinii and Liolaemus melanops. The latter group is constituted almost exclusively by Patagonian lizards, and it is ourfocal group. In the present work we describe three new species belonging to the Liolaemus melanops group. One of thenew taxon described, Liolaemus tromen sp. nov., is related to the Liolaemus fitzingerii clade, inhabits in the Center-Westof Neuquén Province, and was confused initially with Liolaemus hermannunezi, a mountain Chilean species. The secondspecies described, Liolaemus purul sp. nov., belongs to the Liolaemus telsen clade, inhabits in the center and north-westof Neuquén Province, and was confused first with Liolaemus boulengeri and then with Liolaemus loboi. While the thirdspecies, Liolaemus dumerili sp. nov., is basal of the L. goetschi group, inhabits in the center-south of Río Negro provinceand was considered as Liolaemus melanops. In addition, we present a phylogenetic analysis based in the morphology and we contribute with a dichotomic key for males of the Liolaemus melanops group.

Phymaturus is a clade of lizards that occurs at moderate to high elevations in western Argentina and the adjacent central region of Chile, as well as in various volcanic plateaus of the Patagonian region of Argentina. This genus had previously been divided into two groups: the patagonicus and the palluma groups. In this study, we analyzed relationships within the patagonicus group. The data set was built for 23 species plus nine other terminal taxa of undetermined taxonomic status. In total, 10,631 bp (ND4, Cytb, 12S, COI, five protein coding nuclear genes and seven anonymous nuclear loci) and 254 morphological characters were analyzed in a combined data set for 35 ingroup taxa and nine outgroups. We also ran separate DNA sequence and morphological data sets. We identified four main clades, and revealed congruencies and incongruences with previous studies. The indistinctus clade is recovered as the most basal within the patagonicus group in the strict parsimony analysis, while the somuncurensis clade is the most basal under Bayesian inference. The previously recovered calcogaster clade resulted paraphyletic in both analyses and part of their species are included in a redefined somuncurensis clade. We found low support at basal nodes provoked in part by contradictory evidence shown by rogue taxa. We show the phylogenetic information given by each partition/marker and how they contribute to relationships found in the total evidence analysis. We discuss the phylogenetic position of Phymaturus manuelae, Phymaturus tenebrosus, and Phymaturus patagonicus.