大雪山地域で捕獲されたトウキョウトガリネズミSorex minutissimus

抄録

Although Sorex minutissimus has been found in the North, South and East of Hokkaido, the authors found five specimens, for the first time, in central Hokkaido (four males and one female). The specimens were captured at altitudes ranging from 840-890 meters. The discovery of the species at this altitude is no less important than the discovery in this new region. For each of the five specimens captured, the fully developed teeth indicated they were adult members of the species. In a previous report by the authors (Kadosaki et al. 2000), the head and body, forefoot, hind foot and tail lengths of specimens captured in the Sarobetsu area were documented. The respective lengths of the specimens discovered in central Hokkaido were smaller. Therefore it may be concluded that the members of the species found in central Hokkaido are smaller. The five specimens found in Daisetsuzan and the fifteen specimens found around Sarobetsu, all had dark to ginger brown heads, bodies and tails with the undersides a grey color. The identifying features of this species are : five unicuspids with red tips; a tail length less than 34mm ; a tail width less than 2mm and a lot of short fine hair on the tail. Another identifying feature is that for specimens with severed tails, the hind foot length, excluding the length of the claw, is less than lOmm. Other species captured in the same area include : C. rex, C. rufocanus, A. argenteus, A. speciosus, S. unguiculatus, S. minutus, indicating they share the same habitat as Sorex minutissimus.