Notes on Polyxenidae of Japan

Abstract

In 1942 Takakuwa and Takashima reported five specimens of Polyxenidae (Pselaphognatha, Diplopoda) which was collected by Mr. Toma at Shuri on Oki-nawa Island. They identified them as Monographis kraepelini, the species of which was established by Attems based on a specimen from Buitenzorg, Java. This record constitutes the first occurrence of Polyxenidae from the Japanese Islands. Soon after the Pacific war, Mr. Gamo who was a young graduate of the Middle School at that tine succeeded in finding the Polyxenidae on Enoshima Island in Kanagawa Prefecture where those tiny animals were creeping on rocks near the seashore. They are no doubt a species of Pselaphognatha and his finding attracted much attention among scientists and amateur entomologists which gradually lead to further discoveries frog various parts of Japan. Mr. Miyosi, the myriapodologist, considered these Japanese specimens as the fourth and new species of the Genus Monographis and subsequently named them as takakuwai and further a new subspecies nigricans was described, We propose here the third subspecies of M. takakuwai based on specimens collected at Kinnta, Tokyo:- Monographis takakuwai kinutensis Haga n. subsp. This new race is closely related to the typical takakuwai and nigricans but differs from them by having a different body length;colour of dorsal scuta, dor-sal side of head, ventral side of body and ambulatory legs, the setae of both dorsal and lateral parts; colour of dorsal streaks and caudal hair bundle; and number of barbed hooks in the caudal hair bundle.