蚤类的种间杂交及其分类学意义 (二)思博新蚤×近代新蚤

INTERSPECIFIC HYBRIDIZATION OF FLEAS AND ITSSYSTEMATIC SIGNIFICANCE*

在完成曲棘新蚤（ＮｅｏｐｓｙｌａｔｅｒａｔｕｒａＲｏｔｈｓｃｈｉｌｄ，１９１３）和思博新蚤（Ｎ．ｓｉｂｏｉＹｅｅｔＹｕ，１９９３）的杂交，证明二者杂交可育，不存在生殖隔离后，作者又以思博新蚤（Ｎ．ｓ．）和近代新蚤东方亚种（ＮｅｏｐｓｙｌａｐｌｅｓｋｅｉｏｒｉｅｎｔａｌｉｓＩｏｆｅｔＡｒｇｙｒｏｐｕｌｏ，１９３４）（Ｎ．ｐ．）为亲本进行了杂交试验。在平皿湿滤纸上培育出裸蛹，在蛹期即将雌雄分开以获得单性成虫，保证了亲代在用于杂交前同种蚤两性间无交配。设正交、反交和子代自交三种组合。以雄性第９腹板后臂鬃的形态、第８腹板鬃序和可动突形状作为判定杂交后代的形态学指征。正交组产生了Ｆ１～Ｆ３代，Ｆ１接近Ｎ．ｓ．型，Ｆ２多呈中间型，Ｆ３则趋向Ｎ．ｐ．型。反交组仅获Ｆ１，有待进一步做重复试验。就正交能产生Ｆ１～Ｆ３代这一结果看，可以认为两亲本杂交可育，二者不存在生殖隔离，因此并非不同的种，而是属于同一物种，但两者之间已有明显的分化。

A series of interspecific hybridizations including the direct cross,reciprocal cross and the filial inbreedings,has been made with neopsylla siboi Ye et Yu,1993(N.s.)and Neopsylla pleskei orientalis  Ioff et Argyropulo,1934(N.p.),two morphologically confirmed species,as the parents.A platewet filter paper method was employed to get the naked pupae,which made it possible to avert the intraspecific hybridization.The morphology of both the telomere and the bristles on the horizontal arm of st.9 of the male fleas and the bristle order of st.8,were employed as the criteria for the bred progeny. \ \ The crossability and crosscompatibilit have been proved by direct cross(with N.s. as female parent and N.p. as male parent),F1～F3 generations were successfully obtained,while only F1 generation emerged in reciprocal cross(with N.p. as female parent and N.s. as male parent) although coupling and oviposition were observed among the F1 progeny.Anyhow,it may be considered that the parents are belonging to the same species,rather than two independent species,with reference to thg specific definition. In view of the fact that the systematics of Siphonaptera (and also other orders of insedcts) is mostly based on the morphology,it′s hard to completely avoid the subjective activties and voluntary treatments,thus the suystematic methodology and the criteria of Siphonaptera should be improved with genetic and modern biotechniques.