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We describe a new species of Lepidodactylus from Umboi Island, just to the west of New Britain. It is a member of the Lepidodactylus guppyi Group and can be distinguished from all other Melanesian Lepidodactylus by aspects of digital scalation, digital webbing, enlarged femoral/precloacal scales, and color pattern. It is genetically distinct from its closest congeners, and genetic and morphological data indicate that the new species is most similar among named species to Lepidodactylus guppyi from the Solomon Islands, but it diverged from this species and other close relatives approximately 8 MYA or longer at a time prior to the existence of the island that it now occupies. The new species is known from only three individuals collected on a single tree, and efforts to find more animals in what seemed good habitat nearby were unsuccessful. This duplicates the pattern of apparent rarity seen for many Lepidodactylus species. Sufficient habitat exists on Umboi Island for arboreal geckos, suggesting that the species is not actually endangered but is ecologically cryptic. However, lack of needed information leads us to assess this species’ conservation status as Data Deficient.
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Redescription of Lepidodactylus flaviocularis (Squamata: Gekkonidae), with the description of a new species from Makira Island, Solomon Islands
Several species of geckos of the genus Lepidodactylus are endemic to the Solomon Islands and very poorly known. I redescribe one of these, L. flaviocularis, from Guadalcanal, based on examination of a second, newly obtained specimen and quantification of diagnostically useful features of the digits. I also describe a closely related new species from nearby Makira Island in the southern Solomon Islands. Both species are distinguished by their large number of undivided subdigital lamellae, extensive toe webbing, and a continuous row of enlarged precloacal/femoral scales. The new species is distinguished from L. flaviocularis by a number of scalational features and the color of the circumorbial scales. Both species are inhabitants of interior forest, and it remains uncertain whether they are naturally rare, rare due to interactions with invasive species, or simply have cryptic ecological habits, though the last seems most likely. Current evidence for both species is consistent with the taxon-cycle hypothesis, which posits ecological displacement to inland habitats of ancient island inhabitants by newer colonizers, but this remains to be critically tested. The limited pool of specimens available for both species necessitates assessing the IUCN conservation status of each as Data Deficient.
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- Award ID(s):
- 2230919
- PAR ID:
- 10511537
- Publisher / Repository:
- Zootaxa
- Date Published:
- Journal Name:
- Zootaxa
- Volume:
- 5339
- Issue:
- 6
- ISSN:
- 1175-5326
- Page Range / eLocation ID:
- 562 to 576
- Subject(s) / Keyword(s):
- endemism, gecko, IUCN red list, rarity, taxon cycle
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.11646/zootaxa.5339.6.5
