A typhlopid hotspot in the tropics: increased blindsnake diversity in the Kimberley region of Western Australia with the description of a new Anilios species (Serpentes: Typhlopidae)

Abstract

The blindsnake genus Anilios is the most speciose genus of Australian snakes and represents one of the most species rich genera of snakes globally. Morphological and molecular studies continue to highlight further diversity within the genus, suggesting true species diversity is far greater than currently known. A morphologically distinct new species of blindsnake, Anilios vagurima sp. nov., is described from a single specimen collected from Mornington Wildlife Sanctuary in the Kimberley region of Western Australia in 2006. The species differs from all other Anilios species in possessing 22 midbody scale rows, 542 dorsal body scales, head moderately trilobed in dorsal view, rounded in profile view, and a unique configuration of the nasal cleft. The cleft originates at the second supralabial and arcs anterodorsally to the nostril and then posterodorsally to lie nearly parallel to rostral-nasal suture within the apex of nasal scale, where it is clearly visible in dorsal view.

Paleoenvironmental models for Australia and the impact of aridification on blindsnake diversification

“…Finally, another potential explanation for the negative correlation between diversification and aridity is the limited sampling of Australian blindsnakes, particularly in major sand deserts (Pepper & Keogh, 2021) or even in areas of high cryptic diversity such as the Kimberley (Ellis, 2019). The current phylogeny is missing 12 described species (Tiatragul et al, 2023), such as the arid‐adapted A. fossor and A. minimus , and the true diversity has been estimated to exceed 56 species (Ellis, 2019; Marin, Donnellan, Hedges, Doughty, et al, 2013; Marin, Donnellan, Hedges, Puillandre, et al, 2013). It is possible that unrecognised species may be hidden under nominal species and that these missing lineages have diversified more recently when aridity is high.…”

“…Yet, here we found no difference between speciation rates in arid-and mesic-adapted lineages which is inconsistent with this hypothesis. Finally, another potential explanation for the negative correlation between diversification and aridity is the limited sampling of Australian blindsnakes, particularly in major sand deserts (Pepper & Keogh, 2021) or even in areas of high cryptic diversity such as the Kimberley (Ellis, 2019).…”

Underground Down Under: Skull anatomy of the southern blind snake Anilios australis Gray, 1845 (Typhlopidae: Serpentes: Squamata)

“…The members of this clade are generally small in size, not surpassing 30 cm in length, although one fossil is known to have been over 1 m in length (Fachini et al, 2020), and this is rivalled by living members of the genus Afrotyphlops (Broadley & Wallach, 2009). The Australo-Papuan typhlopid genus Anilios (Gray, 1845;Typhlopidae [Asiatyphlopinae]) represents the 11th most speciose snake genus globally, with 48 currently recognized species (Ellis, 2019;Uetz, Freed, & Hošek, 2020). By subsequent designation (Stejneger, 1904;p.…”

“…A. australis is a moderately robust species, endemic to southwestern Australia (Marin et al, 2013;Wilson & Swan, 2021). The species has been suspected to comprise multiple unnamed taxa, however, molecular evidence indicates only a single as yet unnamed taxon, occurring in the northern extent of the species' distribution (Ellis, 2019;Marin et al, 2013). Despite the high level of diversity currently recognized within Anilios, recent molecular and morphological studies indicate that true species diversity remains poorly defined, and numerous unnamed taxa persist, many as cryptic species within currently described taxa (e.g., Ellis, 2016;Ellis, 2019;Ellis, Doughty, Donnellan, Marin, & Vidal, 2017;Marin et al, 2013).…”

“…The species has been suspected to comprise multiple unnamed taxa, however, molecular evidence indicates only a single as yet unnamed taxon, occurring in the northern extent of the species' distribution (Ellis, 2019;Marin et al, 2013). Despite the high level of diversity currently recognized within Anilios, recent molecular and morphological studies indicate that true species diversity remains poorly defined, and numerous unnamed taxa persist, many as cryptic species within currently described taxa (e.g., Ellis, 2016;Ellis, 2019;Ellis, Doughty, Donnellan, Marin, & Vidal, 2017;Marin et al, 2013). Taxonomic studies in this genus are largely hindered by the often limited (or completely lacking) diagnostic morphological features, presumably resulting from constraints imposed by their fossorial nature (Ellis, 2016).…”