Kennedy C R, Bush A O
Department of Biological Sciences, Hatherly Laboratories, University of Exeter, UK.
Parasitology. 1992 Feb;104 Pt 1:189-97. doi: 10.1017/s0031182000060935.
Using data sets derived from published literature, the contribution of congeneric species to helminth component community richness is evaluated. Consideration of the frequency distribution of congeners in relation to host and parasite groups reveals that the distributions are unimodal, that singletons are the commonest class and that the frequency of occurrence of congeners decreases with increasing number of species per genus. Congeners may be found in any group of hosts or parasites, but are more common amongst cestodes of aquatic birds. Two patterns of occurrence of congeneric species are recognized: one in which from a few to multiple congeners are found within a single helminth genus, exemplified by dactylogyrid monogeneans and cloacinid nematodes, and the other in which there is a simultaneous occurrence of congenerics and confamilials such that there are several genera involved, but each represented by fewer species, exemplified by strongyles in horses. The question of whether these patterns can be considered examples of species flocks is discussed. We conclude that multiple congeners and species flocks are interesting phenomena but, except in isolated cases, they make insignificant contributions to community richness.
利用从已发表文献中获取的数据集，评估了同属物种对蠕虫组成群落丰富度的贡献。对同属物种相对于宿主和寄生虫类群的频率分布进行考量后发现，这些分布是单峰的，单种属是最常见的类别，并且同属物种的出现频率随着每个属物种数量的增加而降低。同属物种可能存在于任何宿主或寄生虫类群中，但在水鸟的绦虫中更为常见。识别出了同属物种的两种出现模式：一种是在单个蠕虫属内发现从少数到多个同属物种，以指环虫单殖吸虫和克洛阿线虫为例；另一种是同属物种和同科物种同时出现，涉及多个属，但每个属的物种较少，以马的圆线虫为例。讨论了这些模式是否可被视为物种集群实例的问题。我们得出结论，多个同属物种和物种集群是有趣的现象，但除了个别情况外，它们对群落丰富度的贡献微不足道。
