Ivan Ineich

Madagascar velvet geckos, genus Blaesodactylus, are classified in six species distributed over low-elevation sites across most of Madagascar. Based on DNA sequences of one mitochondrial and two nuclear-encoded gene fragments obtained from numerous newly collected tissue samples, we provide an updated review of their molecular variation. Our genetic screening confirms an extended distribution of B. ambonihazo, so far only known from its type locality Ankarafantsika, now reaching northwards to the Sahamalaza Peninsula. Compared to previously available molecular data, we also verify minor range extensions of B. boivini (southeastwards to Bezavona), B. antongilensis (northwards to the Marojejy Massif), and the B. sakalava complex. Samples assigned to B. sakalava according to current taxonomy fell into two mitochondrial sister lineages differing by about 8.5% pairwise distances in the 16S rRNA gene, lack of haplotype sharing in the nuclear-encoded CMOS gene, and various subtle but consistent differences in body proportions and scalation. We conclude that the lineage occurring in the South of Madagascar, encompassing known locations south of Morombe, corresponds to B. sakalava sensu stricto based on its type locality and morphological characters of its name-bearing type; and describe the lineage occurring in the West of Madagascar north of Morombe as a new species, B. ganzhorni sp. nov.

Invasion risks may be influenced either negatively or positively by climate change, depending on the species. These can be predicted with species distribution models, but projections can be strongly affected by the source of the environmental data (climate data source, Global Circulation Models GCM and Shared Socio-economic Pathways SSP). We modelled the distribution ofPhelsuma grandisandP. laticauda, two Malagasy reptiles that are spreading globally. We accounted for drivers of spread and establishment using socio-economic factors (e.g., distance from ports) and two climate data sources, i.e., Climatologies at High Resolution for the Earth’s and Land Surface Areas (CHELSA) and Worldclim. We further quantified the degree of agreement in invasion risk models that utilised CHELSA and Worldclim data for current and future conditions. Most areas identified as highly exposed to invasion risks were consistently identified (e.g. in Caribbean and Pacific Islands). However, projected risks differed locally. We also found notable differences in quantitative invasion risk (3% difference in suitability scores forP. laticaudaand up to 14% forP. grandis) under current conditions. Despite both species native distributions overlapping substantially, climate change will drive opposite responses on invasion risks by 2070 (decrease forP. grandis,increase forP. laticauda). Overall, projections of future invasion risks were the most affected by climate data source, followed by SSP. Our results highlight that assessments of current and future invasion risks are sensitive to the climate data source, especially in islands. We stress the need to account for multiple climatologies when assessing invasion risks.

Context: Skinks comprise the dominant component of the terrestrial vertebrate fauna in Oceania, New Guinea, and Eastern Wallacea (ONGEW). However, knowledge of their diversity is incomplete, and their conservation needs are poorly understood. Aims: To explore the diversity and threat status of the skinks of ONGEW and identify knowledge gaps and conservation needs. Methods: We compiled a list of all skink species occurring in the region and their threat categories designated by the International Union for Conservation of Nature. We used available genetic sequences deposited in the National Center for Biotechnology Information’s GenBank to generate a phylogeny of the region’s skinks. We then assessed their diversity within geographical sub-divisions and compared to other reptile taxa in the region. Key results: Approximately 300 species of skinks occur in ONGEW, making it the second largest global hotspot of skink diversity following Australia. Many phylogenetic relationships remain unresolved, and many species and genera are in need of taxonomic revision. One in five species are threatened with extinction, a higher proportion than almost all reptile families in the region. Conclusions: ONGEW contain a large proportion of global skink diversity on <1% of the Earth’s landmass. Many are endemic and face risks such as habitat loss and invasive predators. Yet, little is known about them, and many species require taxonomic revision and threat level re-assessment. Implications: The skinks of ONGEW are a diverse yet underexplored group of terrestrial vertebrates, with many species likely facing extreme risks in the near future. Further research is needed to understand the threats they face and how to protect them.

Lankascincus dorsicatenatus is an endemic species of litter-skink distributed throughout the wet zone of Sri Lanka (elevations from 15 to 800 m a.s.l.). The recent resurrection of Lygosoma megalops by the recent description of its neotype designated by Batuwita (2019), presently lost, destabilized the taxonomic status of Lankascincus dorsicatenatus. Amarasinghe et al. (2022) synonymized Lygosoma megalops with Lankascincus fallax, and accepted Lankascincus dorsicatenatus as a valid taxon. Deraniyagala (1953) described Sphenomorphus dorsicatenatus based on a holotype and three paratypes. All the types are lost except one paratype at the National Museum of Sri Lanka, Colombo, Sri Lanka (NMSL), but it is in bad condition. Therefore, with a comparative discussion on the status of ‘Lankascincus megalops‘, here we designate a neotype for Lankascincus dorsicatenatus for clarification of the taxonomic status and stabilize the nomen. A discussion on the distribution and conservation of Lankascincus dorsicatenatus is also provided.

Bronchocela jubata Duméril and Bibron, 1837 is one of the commonest species of the genus, known mostly from Java Island and southern parts of Sumatra. It is rare in Bali and Borneo. The juveniles are often confused with its morphologically similar congener, B. cristatella, which occurs widely throughout the Indonesian Archipelago and Peninsular Malaysia. We examined the morphology of B. jubata based on museum specimens including its two available syntypes, and redescribed the species based on the lectotype designated herein. We highlight the characters of B. jubata with a morphometric comparison to its sympatric congener B. cristatella from Java Island, Indonesia. Based on the current distribution pattern and the apparent threats, we update the conservation status of B. jubata using IUCN Red List Criteria, and propose that it be considered as a species of Least Concern (LC), endemic to the Greater Sundaic Islands.

The widespread parthenogenetic gecko Lepidodactylus lugubris is comprised of several clonal lineages, at least one of which has been known for some time to have originated from hybridization between its maternal ancestor, Lepidodactylus moestus, and a putatively undescribed paternal ancestor previously known only from remote islands in the Central Pacific. By integrating new genetic sequences from multiple studies on Lepidodactylus and incorporating new genetic sequences from previously sampled populations, we recovered a phylogenetic tree that shows a close genetic similarity between the generally hypothesized paternal hybrid ancestor and a recently described species from Maluku (Indonesia), Lepidodactylus pantai. Our results suggest that the paternal hybrid ancestor of at least one parthenogenetic clone of L. lugubris is conspecific with L. pantai and that the range of this species extends to Palau, the Caroline Islands, the Kei Islands, Wagabu, and potentially other small islands near New Guinea. Deeper genetic structure in the western (Palau, Maluku) versus eastern (eastern Melanesia, Micronesia, Polynesia) part of this species’ range suggests that the western populations likely dispersed via natural colonization, whereas the eastern populations may be the result of human-mediated dispersal. The potential taxonomic affinities and biogeographic history should be confirmed with further morphological and genetic analyses, including research on L. woodfordi from its type locality, which would have nomenclatural priority if found to be conspecific with L. pantai. We recommend referring to the wide-ranging sexual species as Lepidodactylus pantai until such a comparison can be made.