A Morphological Study ofCynops pyrrhogasterfrom the Chita Peninsula: Rediscovery of the “Extinct” Atsumi Race Endemic to Peninsular Regions of Aichi Prefecture, Central Japan

Abstract

In the Japanese fire-bellied newt, Cynops pyrrhogaster, six local races were reported (Atsumi, Hiroshima, Kanto, Sasayama, Tohoku, and Intermediate) on the basis of morphological and ethological traits. Among them, the Atsumi race was reported only from a locality of the Atsumi Peninsula, Aichi Prefecture, but this race has been thought to be extinct after the 1960s. In the present study, we collected C. pyrrhogaster at a wetland of the Chita Peninsula, which is located west of the Atsumi Peninsula. The specimens resembled the Atsumi race in dorsal and ventral color pattern, absence of male nuptial color, small body size, and elongated filamentous process of tail tip. Newts from Chita differed from the Atsumi race in the tail height/tail length ratio, but this value was highly variable even among populations within another race (the Intermediate race). Judging from these results, we suggest that C. pyrrhogaster from the Chita Peninsula should be regarded as a part of the Atsumi race, which has long been thought to be extinct. Unfortunately, C. pyrrhogaster at Chita is also threatened with extinction, and immediate protection is seriously needed to prevent this enigmatic local race from complete extinction.