The phylogenetic position of ridley's worm lizard reveals the complex biogeographic history of New World insular amphisbaenids.

The archipelago of Fernando de Noronha (FN) is located in the Equatorial South Atlantic Ocean, at 375 km off the northeastern coast of Brazil. Its endemic vertebrate land fauna is restricted to only six species, and three main hypotheses have been proposed to explain their presence in the archipelago. These hypotheses suggest FN had alternative biogeographic connections with: 1) the West Indies; 2) the South America mainland; or 3) Africa. Here, we evaluate for the first time the phylogenetic position of Amphisbaena ridleyi within the diversity of Amphisbaenia, and we infer the biogeographic processes that explain its presence in FN and its relationship with amphisbaenids from the West Indies. We analyzed a comprehensive multilocus dataset for Amphisbaenidae using maximum likelihood and time-calibrated Bayesian phylogenetic approaches. Based on our time-calibrated tree, we tested different biogeographic scenarios through historical biogeographic analyses. Our phylogenetic results for the high-level relationships of Amphisbaenia can be parenthetically summarized as (Rhineuridae, (Blanidae, (Bipedidae, (Cadeidae, (Trogonophidae, (Amphisbaenidae))))). Nine highly supported groups of species were recovered among the mainland South American amphisbaenids (SAA), whereas two phylogenetically distant groups of species were inferred for the West Indies: 1) WIC01, an Oligocene lineage present in Cuba and Hispaniola, which is the sister group of all other SAA groups; and 2) WIC02, a Miocene lineage that is restricted to southern Hispaniola and is closely related to Am. ridleyi. We estimated two events of transatlantic dispersal of amphisbaenians from Africa to West Indies: the dispersal of Cadeidae during the Middle Eocene, and the dispersal of the ancestor of Amphisbaena during the transition Eocene/Oligocene. These events were likely affected by the North Equatorial and South Equatorial currents, respectively, which have been flowing westwards since the Paleocene. The ancestral cladogenesis of Amphisbaena during the Late Oligocene is likely related to overwater dispersal events, or alternatively can be associated with the fragmentation of GAARlandia, when WIC01 was isolated in the West Indies, while the remaining groups of Amphisbaena diversified throughout the South American continent. During the Late Miocene, the ancestor of WIC02 dispersed from northern South America to the West Indies, while Am. ridleyi dispersed from the same region to FN. The overwater dispersal of WIC02 was driven by the North Brazilian Current and the dispersal of Am. ridleyi was likely influenced by the periodic shifts in direction and strength estimated for the North Equatorial Counter-Current during the Late Miocene.

A new four-pored Amphisbaena Linnaeus, 1758 (Amphisbaenia, Amphisbaenidae) from the north of Espinhaço Mountain Range, Brazil.

A new species of Amphisbaena is described from the north of Espinhaço Mountain Range, municipality of Caetité, state of Bahia, Brazil. Amphisbaenaamethysta sp. nov. can be distinguished from its congeners by the following combination of characters: (1) snout convex in profile, slightly compressed not keeled; (2) pectoral scales arranged in regular annuli; (3) four precloacal pores; (4) distinct cephalic shields; (5) 185-199 dorsal half-annuli; (6) 13-16 caudal annuli; (7) conspicuous autotomic site between 4th-6th caudal annuli; (8) 16-21 dorsal and ventral segments at midbody; (9) 3/3 supralabials; (10) 3/3 infralabials; and (11) smooth and rounded tail tip. The new species is the 71st species of genus with four precloacal pores, and the 22nd species from the Caatinga morphoclimatic domain. The identification of Amphisbaenaamethysta sp. nov. indicates that the reptile fossorial fauna in the Espinhaço Mountain Range region is far from being completely known and that it may harbour a much greater diversity of endemic taxa.

Amphisbaena mensae Catro-Mello, 2000 is a synonym of Amphisbaena talisiae Vanzolini, 1995 (Squamata: Amphisbaenia: Amphisbaenidae).

Amphisbaena talisiae and A. mensae, two worm lizard species endemic to the Cerrado ecoregion, in central Brazil, are considered synonyms based on morphological characters. With the proposed synonymy, the name A. talisiae has priority of use over A. mensae. Amphisbaena talisiae can be distinguished from its congeners by a series of morphological characters, including a round head, three supralabial and three infralabial scales, postmalar row absent, four precloacal pores without a median hiatus, 205-234 body annuli, 17-29 caudal annuli, 10-14 dorsal and 14-18 ventral segments in a midbody annulus. The species is recorded from southeastern Mato Grosso, eastern Minas Gerais and central Tocantins states in central Brazil, and its conservation status should be changed from Data Deficient to Least Concern.

A new species of the Amphisbaena (Squamata, Amphisbaenidae) from the Brazilian Cerrado with a key for the two-pored species.

Here, we describe a new species of Amphisbaena with two precloacal pores from open Cerrado areas of the municipality of Arenópolis, in the Brazilian state of Goiás. The new species differs from other South American amphisbaenids by the folllowing combination of characters: (1) snout rounded in dorsal view and slightly convex in lateral view; (2) two precloacal pores; (3) 161-176 dorsal half-annuli; and (4) 12-15 tail annuli. Our molecular phylogenetic analysis retrieved a monophyletic Amphisbaena silvestrii group, with A. silvestrii positioned as the sister-group of a clade formed by Amphisbaena anaemariae and the new species described herein. Members of the A. silvestrii group including A. neglecta and A. crisae not added in our phylogenetic analysis are characterized by a relatively small body, two precloacal pores, body coloration with dark and light areas, and lack of specializations on the cephalic or caudal shields. We present a key for two-pored species of Amphisbaena.

Correction: Large-scale molecular phylogeny, morphology, divergence-time estimation, and the fossil record of advanced caenophidian snakes (Squamata: Serpentes).

[This corrects the article DOI: 10.1371/journal.pone.0216148.].

Large-scale molecular phylogeny, morphology, divergence-time estimation, and the fossil record of advanced caenophidian snakes (Squamata: Serpentes).

Caenophidian snakes include the file snake genus Acrochordus and advanced colubroidean snakes that radiated mainly during the Neogene. Although caenophidian snakes are a well-supported clade, their inferred affinities, based either on molecular or morphological data, remain poorly known or controversial. Here, we provide an expanded molecular phylogenetic analysis of Caenophidia and use three non-parametric measures of support-Shimodaira-Hasegawa-Like test (SHL), Felsentein (FBP) and transfer (TBE) bootstrap measures-to evaluate the robustness of each clade in the molecular tree. That very different alternative support values are common suggests that results based on only one support value should be viewed with caution. Using a scheme to combine support values, we find 20.9% of the 1265 clades comprising the inferred caenophidian tree are unambiguously supported by both SHL and FBP values, while almost 37% are unsupported or ambiguously supported, revealing the substantial extent of phylogenetic problems within Caenophidia. Combined FBP/TBE support values show similar results, while SHL/TBE result in slightly higher combined values. We consider key morphological attributes of colubroidean cranial, vertebral and hemipenial anatomy and provide additional morphological evidence supporting the clades Colubroides, Colubriformes, and Endoglyptodonta. We review and revise the relevant caenophidian fossil record and provide a time-calibrated tree derived from our molecular data to discuss the main cladogenetic events that resulted in present-day patterns of caenophidian diversification. Our results suggest that all extant families of Colubroidea and Elapoidea composing the present-day endoglyptodont fauna originated rapidly within the early Oligocene-between approximately 33 and 28 Mya-following the major terrestrial faunal turnover known as the "Grande Coupure" and associated with the overall climate shift at the Eocene-Oligocene boundary. Our results further suggest that the caenophidian radiation originated within the Caenozoic, with the divergence between Colubroides and Acrochordidae occurring in the early Eocene, at ~ 56 Mya.

A new four-pored Amphisbaena Linnaeus, 1758 (Amphisbaenia, Amphisbaenidae) from Brazilian Amazon.

A new species of Amphisbaena is described from the Brazilian Amazon, within the area impacted by the Teles Pires hydroelectric power plant, Jacareacanga municipality, State of Pará. Amphisbaena hoogmoedi sp. nov. can be diagnosed from its congeners by the following combination of characters: snout convex in profile view, sligthly compressed not keeled; pectoral scales arranged in regular annuli; conspicuous autotomic site between 7th-8th caudal annuli; 247-252 dorsal half-annuli; 27 caudal annuli; tail length 9.5-10.4% of snoutvent length; four precloacal pores arranged in sequence; three supralabials; a rounded tail; 22-24 dorsal segments in midbody annulus; postmalar row absent; head length 2.1-2.9% of snout-vent length; prefrontals length 46.6-49.5% of head length; prefrontals suture length 38-44.6% of head length; small malar length 10.6-13.4% of ventral length of head ; second infralabial length 33.8-38.5% of head length; ventral length of head 2.7-2.9% of snout-vent length; mouth length 80.2-81.8% of head length; third infralabial length 16.4-19.6% of head length; snout length 62.5-78.6% of head length; ocular length 23.4-26.2% of head length; mental length 23.2-25.4% of ventral length of head; postmental length 27.2-31.3% of ventral length of head; frontals suture length 23.4-32.3% of head length; postocular width 25-31.9% of maximun width of head; first supralabial length 24.9-30.6% of head length; second supralabial length 27.7-30% of head length and second supralabial height 26.9-28.8% of maximun head height. The hemipenis is bilobed, capitate and with lateral lamellae on the lobes; with a centrally-positioned spermatic groove, bifurcated at the base of the lobes, and with each branch extending to the tip of organ.

A new species of Amerotyphlops from Northeastern Brazil, with comments on distribution of related species.

We describe a new species of Amerotyphlops from an upland forest enclave in the state of Paraíba, Northeastern Brazil. The new species is distinguished from the other seven South American species of Amerotyphlops by the combination of the following characters: nasal suture incomplete; rostral scale oval and yellowish cream with some dark brown spots; four supralabial scales; three infralabial scales; rows of scales around the body 18/18/18; middorsal scales from 204 to 225; dorsum with twelve to thirteen rows of scales dark brown and belly with four to five rows of scales immaculate yellowish cream; caudal spine dark brown; subcaudal scales 8-10 in female and 11-13 in males; maximum total length 233 mm. The new species is morphologically similar to A. amoipira and A. paucisquamus, sharing 18/18/18 rows of scales around the body and a small overlap of counts of middorsal scales.