Abstract
Literatures on a squirrel flea, Monopsyllus indages (Rothschild, 1908) occurring in Japan were briefly reviewed. M. indages lis Ono, 1956 was recently synonymized by Sakaguti and Jameson, 1962, but, based on new materials, the author made further investigation and came to a conclusion that these two subspecies could be separated by the following key : The structure of apical membrane of sternite VIII complicated (Fig.A, 4-6); posterior arm of sternite IX rather broad and stout (Fig. A, 7-10); aedeagal chrochet curves and pointed at apex (Fig. A, 1-3); in Hokkaido‥‥‥M. indages indages Apical membrane of sternite VIII simple (Fig. B, 4-6); postrior arm of sternite IX rather slender (Fig. B, 7-10); aedeagal chrochet broad and straight and terminated bluntly (Fig. B, 1-3) in Honshu and Shikoku‥‥‥‥‥‥‥‥‥‥‥‥‥M. indages lis Females of two subspecies are unseparable at present.
