The Distribution of Distinct Karyomorphs of Crocothemis servilia DRURY (Anisoptera, Libellulidae) in Kyushu and the South-western Islands of Japan The Distribution of Distinct Karyomorphs of Crocothemis servilia DRURY (Anisoptera, Libellulidae) in Kyushu and the South-western Islands of Japan

We examined the chromosomes of Crocothemis servilia using specimens collected in the mainland of Kyushu and on the south-western islands of Japan, covering an area from northern Kyushu through Okinawa to Yonaguni-jima. The result showed that all the specimens from Amami-oshima and localities south of it had 2n ♂=25, which was the same as the specimens KIAUTA (1983) found in Taiwan, whereas all the specimens from Yaku-shima and localities north of it had 2n ♂=24, corresponding to the karyomorph which KIAUTA (1983) found in specimens from Osaka, Japan. To compare the body size of the dragonflies from different localities the wing length of the specimens was measured. The specimens collected in the mainland of Kyushu are significantly larger than those of other localities. However, there are no significant differences in wing length between the specimens of Tanega-shima and Yaku-shima and those of Amami-oshima～Yonaguni-jima. Therefore, wing length does not seem to reflect directly the karyological differences described above.

We examined the chromosomes of Crocothemis servilia using specimens collected in the mainland of Kyushu and on the south-western islands of Japan, covering an area from northern Kyushu through Okinawa to Yonaguni-jima. The result showed that all the specimens from Amami-oshima and localities south of it had 2n ♂=25, which was the same as the specimens KIAUTA (1983) found in Taiwan, whereas all the specimens from Yaku-shima and localities north of it had 2n ♂=24, corresponding to the karyomorph which KIAUTA (1983) found in specimens from Osaka, Japan. To compare the body size of the dragonflies from different localities the wing length of the specimens was measured. The specimens collected in the mainland of Kyushu are significantly larger than those of other localities. However, there are no significant differences in wing length between the specimens of Tanega-shima and Yaku-shima and those of Amami-oshima∿Yonaguni-jima. Therefore, wing length does not seem to reflect directly the karyological differences described above.