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species and subspecies of Geckolepis
(C) Geckolepis bekira sp. nov.; (B) G. spania sp. nov.
Vences, Glaw, Köhler, Miralles, Preez, Preick, Rakotoarison, Scherz, Hofreiter and Petzold, 2026 |
Abstract
Fish-scale geckos (Geckolepis), endemic to Madagascar and the Comoro Islands, are nocturnal, arboreal lizards with large, imbricate scales that can be shed and regenerated in their entirety, most likely as an antipredator mechanism. Their species-level taxonomy has remained partly unresolved because morphology alone has proven insufficient to reliably assign genetic lineages to scientific names. Here, we use a museomics approach to extract and shotgun-sequence DNA from twelve liquid-preserved historical and mostly name-bearing type specimens of six historical nomina in the genus, and assemble sequences of the mitochondrial genes for 12S rRNA, 16S rRNA, and nd4 for ten of these specimens. Despite relatively low coverage, the assembled sequences robustly placed all these type specimens in a phylogenetic tree with 113 ingroup samples collected across Madagascar. Our results demonstrate the efficiency of this approach to recover mitochondrial evidence for taxonomic purposes, but also show its failure to recover reads matching single-copy nuclear genes. We discuss the promise of a renewed focus on nuclear ribosomal genes as complementary nuclear-encoded DNA barcodes for vertebrates, as we found 18S rRNA sequences to be well-represented among the reads of the historical specimens studied here. Based on evidence from the mitochondrial tree, two nuclear-encoded genes (C-MOS, RAG-1), and morphology, we resurrect G. typica var. modesta Methuen & Hewitt, 1913 as a full species, G. modesta, from north-western Madagascar, confirm the current use of the name G. maculata Peters, 1880 for specimens from northern and eastern Madagascar, of G. polylepis Boettger, 1893 for specimens from western and north-western Madagascar, and of G. typica Grandidier, 1867 for specimens from southern and south-western Madagascar. We also recognize G. typica var. anomala Mocquard, 1902 as a subspecies, G. typica anomala, and confirm G. petiti Angel, 1942 to be a synonym of this subspecies. We also describe two new species, G. bekira sp. nov. and G. spania sp. nov. from northern Madagascar. The new classification provides a robust baseline to identify the remaining taxonomic issues in the genus and tackle them, preferably using genomic approaches which are also promising to better understand the molecular mechanisms of scarless wound healing and skin regeneration in these geckos.
Squamata, Gekkonidae, Geckolepis spania sp. nov., Geckolepis bekira sp. nov., Madagascar, museomics, archival DNA, Pisces
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| Representative photos in life of all species and subspecies of Geckolepis according to the classification proposed herein. All specimens except G. modesta and G. maculata from Manombo correspond to genotyped individuals. Not to scale. |
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Photos of the preserved holotypes of the two new species described herein,
Geckolepis spania sp. nov. and Geckolepis bekira sp. nov.
For each species, lateral, dorsal and ventral views of head, and dorsal view of entire specimen are shown. |
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Photos in life of the holotypes of the two new species described herein.
(A, B) Geckolepis spania sp. nov., holotype, probably a subadult, ZSM 2124/2007 (FGZC 1140) from Ankarana.
(C, D) Geckolepis bekira sp. nov., the adult male holotype ZSM 1523/2008 (FGZC 1971) from Montagne des Français. |
Geckolepis bekira sp. nov.
Diagnosis. Assigned to the genus Geckolepis based on molecular phylogenetic relationships and body covered with large, imbricated scales. Based on morphological data of Lemme et al. (2013), characterized by snout–vent length <54 mm, 25–28 scales around midbody, 33–43 ventral scale rows, condition A or B of mental scale, eight supralabials, and usually a dark stripe from eye to ear opening. The new species differs from G. humbloti, G. maculata, G. megalepis and G. modesta by a smaller body size (SVL in these species reaching up to 65–75 mm), from G. megalepis and G. modesta furthermore by more scales around midbody (25–28 vs. 17–25), and from G. megalepis also by more ventral scale rows (33–43 vs. 27–32); from G. typica by a different condition of mental scale (A or B vs. D); from G. polylepis by having fewer ventral scale rows (33–43 vs. 48–55) and more scales around midbody (25–28 vs. 35–38). The new species can be differentiated from all other species and lineages in the genus complex by numerous diagnostic nucleotide positions in the mitochondrial genome. MolD identified for the nd4 fragment a robust diagnostic nucleotide combination of an “A” at site 904, a “C” at site 975, and a “T” at site 1002 (positions relative to the full nd4 gene of Geckolepis).
Etymology. The species name is derived from the Malagasy words be (= big) and kira (= scale), referring to the large imbricated scales that distinguish this and other species of Geckolepis from other Malagasy geckos. The species epithet is an invariable noun in apposition to the generic name.
Geckolepis spania sp. nov.
Diagnosis. Assigned to the genus Geckolepis based on molecular phylogenetic relationships and body covered with large, imbricated scales. Characterized by small body size (but holotype is probably not adult), 26 scales around midbody, 34 ventral scale rows, condition A of mental scale, 7–8 supralabials, and presence of a dark stripe from eye to ear opening. The new species differs from G. modesta and G. megalepis by more scales around midbody (26 vs. 17–25), and from G. megalepis also by more ventral scale rows (34 vs. 27–32); from G. maculata (A+B) by more scales around midbody (26 vs. 22–25); from G. maculata (C) by fewer ventral scale rows (34 vs. 36–42); from G. humbloti by a larger number of supralabials compared to most specimens of that species (7–8 vs. 5–7); from G. typica by a different condition of mental scale (A vs. D); from G. polylepis by having fewer ventral scale rows (34 vs. 48–55) and fewer scales around midbody (26 vs. 35–38); reliable morphological differentiation from G. bekira is not possible at present. The new species can be differentiated from all other species and lineages in the genus complex by numerous diagnostic nucleotide positions in the mitochondrial genome. MolD identified for the nd4 fragment a robust diagnostic nucleotide combination of an “A” at site 876, and a “C” at site 943 (positions relative to the full nd4 gene of Geckolepis).
Etymology. The species name is a latinized adjective derived from Greek σπάνιος (spánios = rare), used in the feminine gender in agreement with the genus name. It refers to the rare occurrence of this species, which is known from a single collected specimen, despite numerous herpetological explorations of its type locality, Ankarana National Park.
Miguel VENCES, Frank GLAW, Jörn KÖHLER, Aurélien MIRALLES, Louis Du PREEZ, Michaela PREICK, Andolalao RAKOTOARISON, Mark D. SCHERZ, Michael HOFREITER and Alice PETZOLD. 2026. Reverse Taxonomy of Fish-scale Geckos (
Geckolepis) using shotgun sequencing for museomics-based assignment of Historical Names to Genetic Lineages.
Megataxa. 21(2); 207-232. DOI:
doi.org/10.11646/megataxa.21.2.1 [2026-09-22]
