Cintia Débora Medina

Hacia una Taxonomía Integral: poniendo a prueba especies candidatas relacionadas a Liolaemus buergeri Werner 1907 (Iguania: Liolaemini) mediante análisis morfológicos

Traditional taxonomy has usually been based mainly on characters of external or internal morphology to delimit morpho-species. Recent years have seen the emergence of “integrative taxonomy”, with the objective of integrating the basic concepts and methods of traditional taxonomy with new concepts and methodologies. In this conceptual framework, species are treated as hypotheses and stable species’ hypotheses are those supported by different types of independent characters. The lizard genus Liolaemus has the highest species richness of southern South America, and several clades and complexes have been proposed. One of these is the kriegi group, which includes the species L. buergeri, L. ceii and L. kriegi. Based on three mitochondrial markers, three haploclades closely related to L. buergeri have been proposed as candidate species: L. sp. A, L. sp. B and L sp. C. The aim of this paper is to analyze the morphological variation in the proposed clades and individuals from the type locality of L. buergeri, in order to provide a source of new and independent evidence for the analysis of candidate species proposed for this group. We studied individuals across all the distributional range of L. buergeri and the candidate species. For each specimen we registered morphometric and meristic characters, and precloacal pores in males. We found significant differences among taxa for the analyzed variables, as well as in the degree of sexual dimorphism. The results of these analyzes indicate that the candidate taxa can be identified morphologically and therefore support, based on independent evidence, the “candidate species” hypotheses proposed based on mitochondrial DNA.

Molecular phylogeny of the New World gecko genus Homonota (Squamata: Phyllodactylidae)

The genus Homonota was described by Gray (1845) and currently includes 10 species: Homonota andicola, H. borellii, H. darwinii, H. fasciata, H. rupicola, H. taragui, H. underwoodi, H. uruguayensis, H. williamsii & H. whitii and one subspecies of H. darwinii (H. darwinii macrocephala). It is distributed from 15° latitude south in southern Brazil, through much of Bolivia, Paraguay, Uruguay and Argentina to 54° south in Patagonia and across multiple different habitats. Several morphological taxonomic studies on a subset of these species have been published, but no molecular phylogenetic hypotheses are available for the genus. The objective of this study is to present a molecular phylogenetic hypothesis for all the described species in the genus. We sequenced two mitochondrial genes (cyt‐b & 12S: 1745 bp), seven nuclear protein coding (RBMX, DMLX, NKTR, PLRL, SINCAIP, MXRA5, ACA4: 5804 bp) and two anonymous nuclear loci (30Hb, 19Hb: 1306 bp) and implemented traditional concatenated analyses (MP, ML, BI) as well as species‐tree (*beast) approaches. All methods recovered almost the same topology. We recovered the genus Homonota as monophyletic with strong statistical support. Within Homonota, there are three strongly supported clades (whitii, borellii and fasciata), which differ from those previously proposed based on scale shape, osteology, myology and quantitative characters. Detailed morphological analyses based on this highly resolved and well‐supported phylogeny will provide a framework for understanding morphological evolution and historical biogeography of this phenotypically conservative genus. We hypothesize that extensive marine transgressions during Middle and Late Miocene most probably isolated the ancestors of the three main clades in eastern Uruguay (borellii group), north‐western Argentina‐southern Bolivia (fasciata group), and central‐western Argentina (whitii group). Phylogeographic and morphological/morphometric analyses coupled with paleo‐niche modelling are needed to better understand its biogeographical history.

Lagartijas de la provincia de Santa Cruz (Argentina): distribución geográfica, diversidad genética y estado de conservación

En este trabajo se presenta una actualizacion de las caracteristicas geograficas, geneticas y de conservacion de la herpetofauna de la provincia de Santa Cruz. Utilizando ~ 1500 registros de presencia, se realiza un inventario biologico actualizado y se incluyen mapas de distribucion, fotos a color, comentarios geneticos y estatus de conservacion para las lagartijas de Santa Cruz. El numero de especies de lagartijas distribuidas en esta provincia es de 29, sin embargo tres de estas no presentan registros actuales. En base a los patrones geneticos se identifican al menos diez especies candidatas, linajes no descriptos con suficiente diferenciacion genetica como para representar especies nuevas y que necesitan otras fuentes de evidencia para avalar su estatus especifico. En este trabajo se combina la informacion tradicionalmente presentada en inventarios biologicos con datos geneticos, de distribucion y estatus de conservacion; mas alla de la novedosa integracion realizada, este trabajo tiene la potencialidad de guiar el desarrollo de estudios detallados, en los que se puedan identificar (entre otras) zonas tanto para conservacion como para explotacion sustentable, asi como tambien puede acelerar la descripcion de nuevos taxa llenando los vacios en el conocimiento de la taxonomia alfa.

Molecular phylogenetic relationships of the lizard clade Liolaemus elongatus (Iguania: Liolaemini) with the description of a new species from an isolated volcanic peak in northern Patagonia

A new species of the Andean-Patagonian Liolaemus elongatus clade is described. Liolaemus crandalli sp. nov. differs from other members of its clade by a combination of coloration characters, scale counts and genetic traits. Liolaemus crandalli sp. nov. is known only from an isolated volcanic mountain in northwestern Patagonia above 1500 m.a.s.l. unconnected with other habitat suitable for species of the Liolaemus elongatus clade.

Taxonomic analysis of Paraguayan samples of Homonota fasciata Duméril & Bibron (1836) with the revalidation of Homonota horrida Burmeister (1861) (Reptilia: Squamata: Phyllodactylidae) and the description of a new species

Homonota is a Neotropical genus of nocturnal lizards characterized by the following combination of characters: absence of femoral pores, infradigital lamellae not dilated, claws without sheath, inferior lamellae laterally not denticulate, and presence of a ceratobranchial groove. Currently the genus is composed of 10 species assembled in three groups: two groups with four species, and the fasciata group with only two species. Here, we analyzed genetic and morphologic data of samples of Homonota fasciata from Paraguay; according to Maximum Likelihood and Bayesian inference analyses, the Paraguay population represents an undescribed species. Additionally, morphological analysis of the holotype of H. fasciata (MNHN 6756) shows that it is morphologically different from the banded, large-scaled Homonota commonly referred to as “H. fasciata”. Given the inconsistency between morphological characters of the name-bearing type of H. fasciata and the species commonly referred to as H. fasciata, we consider them as different taxa. Thus, H. fasciata is a species inquirenda which needs further studies, and we resurrect the name H. horrida for the banded, large-scaled Homonota. The undescribed species from Paraguay is similar to H. horrida, but can be differentiated by the high position of the auditory meatus relative to the mouth commissure (vs. low position in H. horrida); and less developed tubercles on the sides of the head, including a narrow area between the orbit and the auditory meatus covered with small granular scales with or without few tubercles (vs. several big tubercles on the sides of the head even in the area between the orbit and the auditory meatus). The new species is distributed in the Dry Chaco in South America. With the formal description of this species, the actual diversity of the genus Homonota is increased to 12 species. Furthermore, we infer phylogenetic relationships for 11 of the 12 described species of the genus, based on 11 molecular markers (two mitochondrial and nine nuclear genes), with concatenated and species tree approaches.

Molecular Phylogeny of the Liolaemus kriegi Complex (Iguania, Liolaemini)

Abstract:  We provide a well-supported phylogenetic hypothesis for all recognized lineages of the Liolaemus kriegi complex based on a multilocus dataset. We used 29 individuals from the eight taxa included in this complex for which we sequenced eight gene regions (two mitochondrial and six nuclear). We implemented maximum likelihood and Bayesian inference methods for the mitochondrial, nuclear, and concatenated sequences and employed BEAST to estimate the species tree. The all genes concatenated analyses and the species trees recovered the L. kriegi complex as monophyletic with high support, including three described species (L. kriegi, Liolaemus ceii, and Liolaemus buergeri) and three previously identified candidate species (Liolaemus sp. A, Liolaemus sp. C, and Liolaemus sp. D), with Liolaemus tregenzai as a closely related taxon. Another previously proposed candidate species (L. sp. B) has a labile topological position that varies depending on the type of markers and analytical methods used. In the mitochondrial gene tree, L. sp. B is recovered within the L. kriegi complex whereas in the “all genes concatenated” analyses and in the nuclear species tree analyses, it is recovered outside of this complex as sister to Liolaemus petrophilus (a representative of the L. petrophilus group). Morphologically, L. sp. B is indistinguishable from L. austromendocinus (also included in the L. petrophilus group); thus, we do not consider L. sp. B as part of the L. kriegi complex. We estimated divergence times for the major clades of the complex based on the species tree hypothesis, and all were inferred to have a Pleistocene origin.

Alternative methods of phylogenetic inference for the Patagonian lizard group Liolaemus elongatus-kriegi (Iguania: Liolaemini) based on mitochondrial and nuclear markers

We present different approaches to a multi-locus phylogeny for the Liolaemus elongatus-kriegi group, including almost all species and recognized lineages. We sequenced two mitochondrial and five nuclear gene regions for 123 individuals from 35 taxa, and compared relationships resolved from concatenated and species tree methods. The L. elongatus-kriegi group was inferred as monophyletic in three of the five analyses (concatenated mitochondrial, concatenated mitochondrial + nuclear gene trees, and SVD quartet species tree). The mitochondrial gene tree resolved four haploclades, three corresponding to the previously recognized complexes: L. elongatus, L. kriegi and L. petrophilus complexes, and the L. punmahuida group. The BEAST species tree approach included the L. punmahuida group within the L. kriegi complex, but the SVD quartet method placed it as sister to the L. elongatus-kriegi group. BEAST inferred species of the L. elongatus and L. petrophilus complexes as one clade, while SVDquartet inferred these two complexes as monophyletic (although with no statistical support for the L. petrophilus complex). The species tree approach also included the L. punmahuida group as part of the L. elongatus-kriegi group. Our study provides detailed multilocus phylogenetic hypotheses for the L. elongatus-kriegi group, and we discuss possible reasons for differences in the concatenation and species tree methods.

New species of Liolaemus (Reptilia, Squamata, Liolaemini) of the Liolaemus donosobarrosi clade from northwestern Patagonia, Neuquén province, Argentina

Two new species of the Liolaemus donosobarrosi clade are described. Liolaemus tirantii sp. nov. and Liolaemus calliston sp. nov. differ from other members of their clade by a combination of coloration characters, morphometric and molecular traits. Liolaemus tirantii sp. nov. is known from three localities separated only a few kilometers from each other and Liolaemus calliston sp. nov. is known only from the type locality. Both species inhabit a region strongly impacted by oil and gas extraction but their conservation status is unknown.

Clelia rustica (Jan, 1863) (Serpentes: Dipsadidae): distribution extension

A new record of the snake Clelia rustica is reported for the province of Neuquen in northwestern Patagonia, extending the distribution by more than 200 km north from previous records; it was known before only from the southernmost regions of the province.