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Triatoma maculata (Hemiptera, Reduviidae, Triatominae) occurs across dry‐to‐semiarid ecoregions of northern South America, where it transmits Trypanosoma cruzi, causative agent of Chagas disease. Using 207 field‐caught specimens from throughout the species' range, mitochondrial(mt) DNA sequence data, and cytogenetics, we investigated inter‐population genetic diversity and the phylogenetic affinities of T. maculata. Mitochondrial DNA sequence analyses (cytb and nd4) disclosed a monophyletic T. maculata clade encompassing three distinct geographic groups: Roraima formation (Guiana shield), Orinoco basin, and Magdalena basin (trans‐Andean). Between‐group cytb distances (11.0–12.8%) were larger than the ~7.5% expected for sister Triatoma species; the most recent common ancestor of these T. maculata groups may date back to the late Miocene. C‐heterochromatin distribution and the sex‐chromosome location of 45S ribosomal DNA clusters both distinguished Roraima bugs from Orinoco and Magdalena specimens. Cytb genealogies reinforced that T. maculata is not sister to Triatoma pseudomaculata and probably represents an early (middle‐late Miocene) offshoot of the 'South American Triatomini lineage'. In sum, we report extensive genetic diversity and deep phylogeographic structuring in T. maculata, suggesting that it may consist of a complex of at least three sibling taxa. These findings have implications for the systematics, population biology, and perhaps medical relevance of T. maculata sensu lato. [ABSTRACT FROM AUTHOR]

The article discusses a study which provides data on the sexual maturity, sexual dimorphism and reproductive output of Liophis anomalus across its distribution area. It describes the reproductive pattern of Liophis anomalus based on examination of museum specimens from its entire distribution area. It tackles the occurrence of multiple clutches, correlation of testicular volume with male size, and the influence of phylogeny and climate on the reproductive patterns of the Xenodontini snake.

The genus Liolaemus is one of the most ecologically diverse and species-rich genera of lizards worldwide. It currently includes more than 250 recognized species, which have been subject to many ecological and evolutionary studies. Nevertheless, Liolaemus lizards have a complex taxonomic history, mainly due to the incongruence between morphological and genetic data, incomplete taxon sampling, incomplete lineage sorting and hybridization. In addition, as many species have restricted and remote distributions, this has hampered their examination and inclusion in molecular systematic studies. The aims of this study are to infer a robust phylogeny for a subsample of lizards representing the Chilean clade (subgenus Liolaemus sensu stricto ), and to test the monophyly of several of the major species groups. We use a phylogenomic approach, targeting 541 ultra-conserved elements (UCEs) and 44 protein-coding genes for 16 taxa. We conduct a comparison of phylogenetic analyses using maximum-likelihood and several species tree inference methods. The UCEs provide stronger support for phylogenetic relationships compared to the protein-coding genes; however, the UCEs outnumber the protein-coding genes by 10-fold. On average, the protein-coding genes contain over twice the number of informative sites. Based on our phylogenomic analyses, all the groups sampled are polyphyletic. Liolaemus tenuis tenuis is difficult to place in the phylogeny, because only a few loci (nine) were recovered for this species. Topologies or support values did not change dramatically upon exclusion of L. t. tenuis from analyses, suggesting that missing data did not had a significant impact on phylogenetic inference in this data set. The phylogenomic analyses provide strong support for sister group relationships between L. fuscus , L. monticola , L. nigroviridis and L. nitidus , and L. platei and L. velosoi . Despite our limited taxon sampling, we have provided a reliable starting hypothesis for the relationships among many major groups of the Chilean clade of Liolaemus that will help future work aimed at resolving the Liolaemus phylogeny., Competing Interests: The authors declare there are no competing interests.