[Herpetology • 2023] Taxonomic Revision and Re-description of Ateuchosaurus pellopleurus (Hallowell, 1861) (Reptilia: Squamata: Scincidae) with Resurrection of A. okinavensis (Thompson, 1912)

 Ateuchosaurus okinavensis (Thompson, 1912)

in Makino, Nakano, Okamoto & Hikida, 2023.

DOI: 10.3897/zse.99.95923

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.

Key Words: lectotypification, morphological diagnosis, Ryukyu Archipelago, scalation

Dorsal, lateral, and ventral views of head scalation of Ateuchosaurus okinavensis (KUZ R77462). See Fig. 4 legend for abbreviations of scale names.

Photograph of a live individual of Ateuchosaurus okinavensis collected at Urasoe Park in Urasoe City, Okinawajima Island (38 m above sea level).

Ateuchosaurus okinavensis (Thompson, 1912)

  Suggested Japanese name: Okinawa-Hime-Tokage

Emended diagnosis: An Ateuchosaurus species characterized by the following: usually fused FrNa and frontal; a pair of frontoparietals that do not contact each other; eight SuCis; anteroposteriorly reduced parietals separated from SuO and pretemporal by EcP; no distinct nuchals; usually six InLas; body size medium (SVL ca. 42–70 mm); widely separated forelimb and hindlimb when appressed; usually 26 or 28 MSRs (mode = 28, 25–28); 54–64 (mode = 59) and 55–67 DMSs (mode = 58) in male and female, respectively; 10–16 TIVs (mode = 13); 10 preanals not enlarged; usually no black stripe on dorsal scale row or one pair of DSRBS; a karyotype of 2n = 28 (Ota et al. 1998).

Tomohisa Makino, Takafumi Nakano, Taku Okamoto and Tsutomu Hikida. 2023. Taxonomic Revision and Re-description of Ateuchosaurus pellopleurus (Hallowell, 1861) (Reptilia, Squamata, Scincidae) with Resurrection of A. okinavensis (Thompson, 1912). Zoosystematics and Evolution. 99(1): 77-91. DOI: 10.3897/zse.99.95923