Increasing the impact of vertebrate scientific collections through 3D imaging: The openVertebrate (oVert) Thematic Collections Network.

The impact of preserved museum specimens is transforming and increasing by three-dimensional (3D) imaging that creates high-fidelity online digital specimens. Through examples from the openVertebrate (oVert) Thematic Collections Network, we describe how we created a digitization community dedicated to the shared vision of making 3D data of specimens available and the impact of these data on a broad audience of scientists, students, teachers, artists, and more. High-fidelity digital 3D models allow people from multiple communities to simultaneously access and use scientific specimens. Based on our multiyear, multi-institution project, we identify significant technological and social hurdles that remain for fully realizing the potential impact of digital 3D specimens.

Galápagos tortoise stable isotope ecology and the 1850s Floreana Island Chelonoidis niger niger extinction.

A consequence of over 400 years of human exploitation of Galápagos tortoises (Chelonoidis niger ssp.) is the extinction of several subspecies and the decimation of others. As humans captured, killed, and/or removed tortoises for food, oil, museums, and zoos, they also colonized the archipelago resulting in the introduction of invasive plants, animals, and manipulated landscapes for farming, ranching, and infrastructure. Given current conservation and revitalization efforts for tortoises and their habitats, here we investigate nineteenth and twentieth century Galápagos tortoise dietary ecology using museum and archaeological specimens coupled with analysis of carbon (δ13Ccollagen and δ13Capatite), nitrogen (δ15N), hydrogen (δD) and oxygen (δ18Oapatite) stable isotopes and radiocarbon dating. We identify that Galápagos tortoise diets vary between and within islands over time, and that long-term anthropogenic impacts influenced change in tortoise stable isotope ecology by using 57 individual tortoises from 10 different subspecies collected between 1833 and 1967-a 134-year period. On lower elevation islands, which are often hotter and drier, tortoises tend to consume more C4 vegetation (cacti and grasses). Our research suggests human exploitation of tortoises and anthropogenic impacts on vegetation contributed to the extinction of the Floreana Island tortoise (C. n. niger) in the 1850s.

On the distribution of Gonyosoma prasinum (Blyth, 1854) and Gonyosoma coeruleum Liu, Hou, Ye Htet Lwin, Wang amp; Rao, 2021, with a note on the status of Gonyosoma gramineum Gnther, 1864 (Squamata: Serpentes: Colubridae).

Based on 85 examined specimens, photographs of living specimens and illustrations published in the literature, we refine the distribution ranges of both Gonyosoma prasinum (Blyth, 1854) and of the recently described species Gonyosoma coeruleum Liu, Hou, Ye Htet Lwin, Wang Rao, 2021, which was not clearly addressed in its original description. We also redescribe the syntypes of Coluber prasinus Blyth, 1854 and the holotype of Gonyosoma gramineum Gnther, 1864, we discuss the status of this latter taxon, and we describe the hemipenial morphology of G. coeruleum.

Speciation and secondary contact in a fossorial island endemic, the São Tomé caecilian.

A period of isolation in allopatry typically precedes local adaptation and subsequent divergence among lineages. Alternatively, locally adapted phenotypes may arise and persist in the face of gene flow, resulting in strong correlations between ecologically-relevant phenotypic variation and corresponding environmental gradients. Quantifying genetic, ecological, and phenotypic divergence in such lineages can provide insights into the abiotic and biotic mechanisms that structure populations and drive the accumulation of phenotypic and taxonomic diversity. Low-vagility organisms whose distributions span ephemeral geographic barriers present the ideal evolutionary context within which to address these questions. Here, we combine genetic (mtDNA and genome-wide SNPs) and phenotypic data to investigate the divergence history of caecilians (Amphibia: Gymnophiona) endemic to the oceanic island of São Tomé in the Gulf of Guinea archipelago. Consistent with a previous mtDNA study, we find two phenotypically and genetically distinct lineages that occur along a north-to-south axis with extensive admixture in the centre of the island. Demographic modelling supports divergence in allopatry (~300 kya) followed by secondary contact (~95 kya). Consequently, in contrast to a morphological study that interpreted latitudinal phenotypic variation in these caecilians as a cline within a single widespread species, our analyses suggest a history of allopatric lineage divergence and subsequent hybridization that may have blurred species boundaries. We propose that late Pleistocene volcanic activity favoured allopatric divergence between these lineages with local adaptation to climate maintaining a stable hybrid zone in the centre of São Tomé Island. Our study joins a growing number of systems demonstrating lineage divergence on volcanic islands with stark environmental transitions across small geographic distances.

Um período de isolamento em alopatria geralmente precede adaptação local e divergência subsequente entre linhagens evolutivas. Alternativamente, fenótipos adaptados localmente podem surgir e persistir apesar de fluxo gênico, resultando em fortes correlações entre variação fenotípica ecologicamente relevante e os gradientes ambientais correspondentes. Quantificar divergência genética, ecológica e fenotípica em tais linhagens pode ajudar a clarificar os mecanismos abióticos e bióticos que estruturam as populações e levam ao acúmulo de diversidade fenotípica e taxonômica. Organismos de baixa vagilidade, cujas áreas de distribuição incluem barreiras geográficas efêmeras, representam um contexto evolutivo ideal para abordar essas questões. Neste estudo, combinamos dados genéticos (mtDNA e SNPs genômicos) e fenotípicos para investigar a história de divergência de cecílias endêmicas da ilha oceânica de São Tomé, no arquipélago do Golfo da Guiné. Consistentemente com um estudo anterior de mtDNA, encontramos duas linhagens fenotipicamente e geneticamente distintas que ocorrem ao longo de um eixo norte-sul, com extensa mistura genética no centro da ilha. Modelagem demográfica suportou um cenário de divergência em alopatria (~ 300 mil anos atrás) seguida de contato secundário (~ 95 mil anos atrás). Ao contrário de um estudo morfológico que interpretou a variação fenotípica latitudinal nessas cecílias como uma clina dentro de uma única espécie amplamente difundida, nossas análises sugerem uma história de divergência de linhagens em alopatria e subsequente hibridização que pode ter confundido os limites das espécies. Propomos que atividade vulcânica durante o Pleistoceno tardio favoreceu divergência alopátrica entre essas linhagens, com adaptação local ao clima mantendo uma zona híbrida estável no centro da Ilha de São Tomé. Nosso estudo se une a um número crescente de sistemas que demonstram divergência entre linhagens em ilhas vulcânicas com transições ambientais marcantes ao longo de distâncias geográficas curtas.

A global catalog of primary reptile type specimens.

We present information on primary type specimens for 13,282 species and subspecies of reptiles compiled in the Reptile Database, that is, holotypes, neotypes, lectotypes, and syntypes. These represent 99.4% of all 13,361 currently recognized taxa (11,050 species and 2311 subspecies). Type specimens of 653 taxa (4.9%) are either lost or not located, were never designated, or we did not find any information about them. 51 species are based on iconotypes. To map all types to physical collections we have consolidated all synonymous and ambiguous collection acronyms into an unambiguous list of 364 collections holding these primary types. The 10 largest collections possess more than 50% of all (primary) reptile types, the 36 largest collections possess more than 10,000 types and the largest 73 collections possess over 90% of all types. Of the 364 collections, 107 hold type specimens of only 1 species or subspecies. Dozens of types are still in private collections. In order to increase their utility, we recommend that the description of type specimens be supplemented with data from high-resolution images and CT-scans, and clear links to tissue samples and DNA sequence data (when available). We request members of the herpetological community provide us with any missing type information to complete the list.