Genetical and behavioral studies on geographic variation and speciation in the genus Eumeces in Japan

在伊豆列岛和日本主岛分别分布有两种，分别是欧卡达和拉卡达。初步的遗传研究表明，伊豆半岛的种群可能属于岛型E. okadae。我们调查了该种在本州的分布，发现了两种的分布边界。西部边界位于富士河，东部边界位于小田原和镰仓之间。等位酶分析表明，小田原种群属于伊豆半岛和伊豆岛的一个种群群，并从小田原种群中获得了一个杂种。1998-1999年对这两种物种进行了物种识别行为实验。第一年的实验失败了，因为繁殖在非常温暖的春天开始得太早。1999年，我们再次进行了这些实验。结果表明，京都市长纹田鼠的雄虫对同种雄虫有区分性。大部分京都雄蚊攻击九州大分雄蚊和对照组雄蚊。它们没有攻击来自伊豆群岛三仓岛和小津岛的冈田姬蚊。在某些情况下，它们试图与它们交配。小田原雄蚊并没有像冈田科雄蚊那样受到攻击。这些结果强烈地表明，两个物种可以相互识别，它们在生物物种中处于Mayr意义上的关系。

Two species, Eumeces okadae and E. latiscutatus have been considered to be distributed in Izu Islands and Japan main islands, respectively. Our Preliminary genetic study suggested that the population of Izu Penisula may belong to the island form, E. okadae. We surveyed the distribution of this species in Hoshu and discovered the distribution boundaries of the two species. The western boundary is situated in Fuji-river, and the eastern boundary is between Odawara and Kamakura. Allozyme analyses showed the Odawara population is included in a cluster of the populaiotns of Izu Peninsula and Izu islands and one hybrid was obtaine from the Odawara population.Behavioral experiments on species recognition between these two species were conducted in 1998-1999. In the first year the experiments were failed because the breeding started too early in tremendously warm spring. In 1999 we conducted again these experiments. Results indicated that males of E. latiscutatus from Kyoto discriminated conspecifice males. Most males of Kyoto attacked males of Oita, Kyushu as well as a control. They did not attack males of E. okadae from Mikura-jima and Kozu-shima, Izu Islands. In some case, they tried to copulate with them. The Odawara males were not attacked as males of E. okadae. These results stongly suggested that two species recognize each other and they are in the relationship in biological species in the sense of Mayr.