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Gymnophthalmids are a diverse lineage of Neotropical lizards that present challenges in the understanding of their phylogenetic relationships and biogeographic history. Using a densely sampled phylogeny and distribution data, we investigated their biogeography at the family level. Dividing South and Central America into 12 regions, we tested six biogeographic models considering dispersal-extinction, vicariance, and founder events. Our analysis revealed high taxonomic and phylogenetic endemism in the Andes, Amazon, and Guiana Shield. The best-fit model identified the Guiana Shield as the likely ancestral area of the family, with dispersal events dominating over vicariance. Key areas for species interchange were the Amazon, Northern Andes, and Guiana Shield. The core regions of diversification included the Andes, Amazon, and Guiana Shield, with elevated species richness and biotic interchange events during the Eocene and Oligocene. The Guiana Shield stood out as a stronghold of gymnophthalmid diversity, driven by dispersal rates and ancient lineages. Our findings challenge previous hypotheses about the diversification of these lizards, suggesting a colonization pattern from lowlands to high elevations rather than the South-to-North Speciation Hypothesis for Andean lineages. [ABSTRACT FROM AUTHOR]

Subsequent to the Miocene (approximately 35 Mya), Borneo has served as an insular refuge and a source of colonization for a broad range of species emigrating to others parts of Sundaland. A phylogeny-based historical biogeographical hypothesis for the Stream Toad genus Ansonia supports multiple instances of an out-of-Borneo scenario. An ancestral range estimation indicates that in situ speciation of Ansonia on the island of Borneo during the Late Miocene and Pliocene (approximately 2-13 Mya) eventually resulted in an invasion of the Philippines, Sumatra, and two independent invasions of the Thai-Malay Peninsula. When collecting material for the biogeographical analysis, a new species of Ansonia, Ansonia khaochangensis sp. nov. was discovered in a limestone cave from the Khao Chang karst tower in Phangnga Province, in southern Thailand. Ansonia khaochangensis sp. nov. can be differentiated from all other species of Ansonia by having a unique combination of morphological and colour pattern characteristics. Phylogenetic evidence based on the mitochondrial genes 12S and 16S indicates that it is nested within a clade of other species distributed north of the Isthmus of Kra. The cave lifestyle of this new species is a unique and a significant departure from lotic environments common to most other species of Ansonia. The reproductive biology of this species is unknown. [ABSTRACT FROM AUTHOR]

Although it is an uncommon distribution in seed plants, many bryophytes occur around the Pacific Rim of north-western North America and eastern Asia. This work focuses on a clade of peatmosses ( Sphagnum) that is distributed around the Pacific Rim region, with some individual species found across the total range. The goals were to infer divergent phylogenetic relationships among haploid species in the clade, assess parentage of allopolyploid taxa, and evaluate alternative hypotheses about inter- and intraspecific geographical range evolution. Multiple data sets and analyses resolved an 'Alaska' clade, distributed across western North America, eastern China and Japan, and an 'Asia' clade that includes western Chinese, Thai, Korean, eastern Chinese and Japanese lineages. Allopolyploids have arisen at least four times in the Pacific Rim clade of Sphagnum subgen. Subsecunda; it appears that all allopolyploid origins involved closely related haploid parental taxa. Biogeographical inferences were impacted by topological uncertainty and especially by the biogeographical model utilized to reconstruct ancestral areas. Most analyses converge on the conclusion that the ancestor to this clade of Pacific Rim Sphagnum species was widespread from Alaska south to eastern Asia, but a northern origin for the Alaska subclade was supported by one of the two biogeographical models we employed, under which it was robust to phylogenetic uncertainty. [ABSTRACT FROM AUTHOR]