Taxonomic revision and re-description of Ateuchosaurus pellopleurus (Hallowell, 1861) (Reptilia, Squamata, Scincidae) with resurrection of A. okinavensis (Thompson, 1912)

Abstract

The scincid lizard Ateuchosaurus pellopleurus (Hallowell, 1861) has been recognized as a single species widely distributed in the Osumi, Tokara, Amami, and Okinawa Groups of the Ryukyu Archipelago, southern Japan. However, a recent molecular phylogenetic study suggested that this skink should be divided into two species: one distributed in the Osumi to Amami Groups, and another distributed in the Okinawa Group. For A. pellopleurus, two extant syntypes collected from an island of the Amami Group were confirmed. Therefore, we identified the species in the Osumi to Amami Groups as A. pellopleurus sensu stricto by designating one of the syntypes as the lectotype for this species. For the species in the Okinawa Group, we resurrected A. okinavensis (Thompson, 1912), of which the type locality is on Okinawajima Island in the Okinawa Group. Ateuchosaurus pellopleurus and A. okinavensis can be differentiated by the following characteristics: usually separated frontonasal and frontal, 8–14 subdigital scales on the fourth toe (mode = 11), and usually two or three pairs of dorsal median scale rows with black stripes in A. pellopleurus; usually fused frontonasal and frontal, 10–16 subdigital scales on the fourth toe (mode = 13), and usually no stripe on the dorsal scales or a pair of dorsal median scale rows with black stripes in A. okinavensis.

Genetic and Morphological Studies on Goniurosaurus kuroiwae (Squamata: Eublepharidae), with a Description of a New Species from the Northern Part of Okinawajima Island, Ryukyu Archipelago, Japan

“…Among the phylogeography of amphibians and reptiles in the Okinawa Islands Group, Iheyajima (and a few nearby islands) populations are often diverged first from other populations, e.g., Hebius pryeri (Kaito and Toda, 2016), Sinomicrurus boettgeri (Kaito et al, 2017), Microhyla okinavensis (Tominaga et al, 2019), and Ateuchosaurus okinavensis (Makino et al, 2020(Makino et al, , 2023, but see the cases of Plestiodon marginatus (Kurita and Hikida, 2014) and Buergeria japonica (Tominaga et al, 2015). Iheyajima and nearby islands are located on a submarine plateau isolated from the major plateau consisting of most other islands, including Okinawajima.…”