著者
阪口 浩平
出版者
日本衛生動物学会
雑誌
衛生動物 (ISSN:04247086)
巻号頁・発行日
vol.11, no.3, pp.137-_144-1_, 1960-08-31 (Released:2016-09-05)
被引用文献数
1 1

The occurrence of true bear flea, Chaetopsylla (Arctopsylla) tuberculaticeps (Bezzi, 1890) in Hokkaido was briefly reported last year (Sakaguti and Jameson 1959). In the present paper the author has taken up again this interesting flea and has pointed out the weakness to establish two subspecies in bear flea, Ch. tuberculaticeps. The materials used in the discussion were obtained from Brown Bear, Ursus arctos yesoensis Lydekker, 1897 at Sounkyo, northeastern foot of Daisetsu mountain group, Ishikari-no-kuni, Hokkaido. Hokkaido is located between the Eurasiatic mainland where the subspecies tuberculaticeps is found and North America where the subspecies ursi occurs. In Hokkaido specimens, the main characters which are divisible are intermediate or complicated in several points. As it was mentioned in Sakaguti and Jameson (1959), the main characters which subspecies ursi is separable from the original form were defined by N. C. Rothschild (1932) and by Hopkins and M. Rothschild (1956) as follows : the antennal club in the male is longer in length and more tapered or nearly parallel-side. The anterior apical angle of phallosome is generally almost rectangular, but there are no clear differences in the female. On the examination of 13 examples of the male specimens collected in Hokkaido, it was found that the length of the antennal club is not so long as that of ursi and its shape is more rounded like tuberculaciceps. The apical angles of phallosome of the Hokkaido specimens, on the other hand, are almost rectangular as ursi. This result is very reasonable from the zoogeographical point of view. Actually all the students have failed to distinguish both subspecies in the female and we have not also been able to distinguish in several important points of the male such as in the shapes of clasper, movable finger and the others. Ioff and Skalon (1954) and Hopkins and M. Rothschild (1956) said that the difference in both Palaearctic and North American representatives of this species is very weak and has not been firmly established. It should be said that there is indeed a single tuberculaticeps in the world although it is rich in the variations. The author has enumerated the collecting-data of the bear flea which were reported by several specialists from the various parts of the world, and the author has refered to the relationships to the hosts, Ursus arctos in the Palaearctic region and Ursus horribilis and Euarctos americanus in North America. Besides, a short account is given on one example of abnormality of the spermatheca with double tail found on the Hokkaido specimens.