taxonID	type	description	language	source
4D5AAC6FFF83FFE2BD5D71E5786EF82D.taxon	description	The BI and ML analyses of the full dataset recovered a non-monophyletic Arthrosaura, with Ar. kockii sister to all other Ecpleopodinae with high support [BI: 1.00 PP; ML: 100 % BP (bootstrap probability)] (Fig. 1) and Ar. testigensis + Ar. sp. from the Chimantá Massif nested in Yanomamia with high support (BI: 1.00 PP; ML: 100 % BP) (Fig. 2). Yanomamia is recovered sister to Arthrosaura with low support (BI: 0.89 PP; ML: 57 % BP). The Ecpleopodinae consensus trees are otherwise similar with most published molecular phylogenies, except for poorly supported nodes (Fig. 1). Other Arthrosaura samples (i. e. except Ar. kockii and Ar. testigensis) are recovered monophyletic with high support (BI: 0.97 PP; ML: 97 % BP) and our results highlight high diversity within the genus, which contains at least five currently unnamed main lineages (hereafter referred to as ‘ species’) in the Amazonian lowlands (Figs 3, 4). However, several relationships among and within clades recovered in Arthrosaura s. s. were poorly supported, and the use of a reduced dataset, including only Arthrosaura + the outgroups, improved the resolution of the phylogenetic relationships within that clade (Fig. 3). Arthrosaura reticulata s. s. is seemingly restricted to western Amazonia in Ecuador and the western Amazonas state in Brazil (Fig. 4), while Arthrosaura versteegii is probably a north-eastern Guiana Shield endemic (Fig. 4). Arthrosaura montigena is a Pantepui endemic, which is here reported for the first time from Guyana at 1411 m elevation (Mount Wokomung; Fig. 4); the two samples have a genetic divergence of 2.0 % in 16 S. Arthrosaura montigena is recovered sister to Ar. reticulata + Ar. sp. 1 with moderate support (BI: 0.97 PP; ML: 83 % BP). Arthrosaura sp. 1 is recovered sister to Ar. reticulata with high support (BI: 1.00 PP; ML: 100 % BP) (Fig. 3) and is found in the western lowlands of Pantepui (Upper Rio Negro and Orinoco) between 50 and 200 m elevation (Fig. 4). Arthrosaura sp. 2 is recovered sister to Ar. versteegii with high support (BI: 0.99 PP; ML: 93 % BP) (Fig. 3) and occurs in the Mitaraka Massif in south-western French Guiana (Fig. 4). Genetic distance on the 16 S fragment between these two samples is 4.2 % (see Table 3) in the absence of any obvious barrier to gene flow. Arthrosaura sp. 3 is possibly endemic to the Sipaliwini region in Suriname and is recovered sister to the clade containing Ar. montigena, Ar. reticulata, Ar. versteegii, Ar. sp. 1, and Ar. sp. 2, albeit with low support (BI: 0.81 PP; ML: 81 % BP); genetic divergence between Ar. sp. 3 and other species in clade A is 4.3 – 7.0 % (Fig. 3, Table 3). A second clade (clade B) containing Ar. sp. 4 (largely distributed in eastern Amazonia, east of the Rio Purus / Negro / Branco and the Essequibo River) and Ar. sp. 5 (apparently restricted to the north-eastern part of the Guiana Shield in eastern French Guiana and Amapá state, Brazil) is recovered sister to all other Arthrosaura with high support (BI: 1.00 PP; ML: 100 % BP) (Figs 3, 4), with Ar. sp. 4 and Ar. sp. 5 recovered as sister-species with high support (BI: 1.00 PP; ML: 100 % BP). Genetic divergences within Ar. sp. 4 (up to 3.8 %, Table 3) suggest that more than one species is represented in that clade (see below). Two clades are recovered within Ar. sp. 5, but with low genetic distance (max 1.6 %), even though these populations are separated by the Oyapock River, a major watercourse in the north-eastern Guiana Shield. Genetic divergences within and among clades in the ‘ barcoding’ 16 S fragment are provided in Table 3.	en	Kok, Philippe J. R., Fouquet, Antoine, Carvajal, Omar Torres, Means, D. Bruce, Rodrigues, Miguel Trefaut (2025): New insights into the molecular phylogenetic relationships of lizards in the Neotropical genus Arthrosaura (Reptilia: Gymnophthalmidae) reveal rampant ‘ cryptic’ speciation in the Guiana Shield. Zoological Journal of the Linnean Society 204 (2): 1-12, DOI: 10.1093/zoolinnean/zlaf045, URL: https://doi.org/10.1093/zoolinnean/zlaf045
