Cox F E
Division of Life Sciences, King's College London, U.K.
Int J Parasitol. 1994 Dec;24(8):1301-16. doi: 10.1016/0020-7519(94)90197-x.
The sporozoans comprise a coherent group of protozoans, with characteristic and complex life cycles, containing 4-5000 species parasitic in invertebrates, particularly annelids and arthropods, and vertebrates. The group is a very successful one but neither its origins nor evolution are well understood. Considerations of traditional life cycles combined with newer methodologies have thrown some light on the evolutionary expansions of the main groups of sporozoans, the gregarines, coccidia, haemosporidians and piroplasms. The sporozoans of economic importance such as the coccidia, malaria parasites and piroplasms have received most attention but the data obtained have also thrown new light on the possible evolution of less well studied groups and it is concluded that conclusions based on simple comparisons of life cycles will have to be modified. It is also clear that humans have played a major part in affecting the distribution and present abundance of many sporozoans of economic significance and probably also those of less importance, and that the rates of evolutionary expansion are much more rapid than previously thought.
孢子虫是一组连贯的原生动物，具有独特而复杂的生命周期，包含4000至5000个物种，寄生于无脊椎动物，尤其是环节动物和节肢动物以及脊椎动物体内。这一类群非常成功，但人们对其起源和进化了解甚少。传统生命周期的研究与新方法相结合，为孢子虫主要类群（簇虫、球虫、血孢子虫和梨形虫）的进化扩张提供了一些线索。具有经济重要性的孢子虫，如球虫、疟原虫和梨形虫，受到了最多关注，但所获得的数据也为研究较少的类群的可能进化提供了新线索，得出的结论是基于生命周期简单比较得出的结论必须加以修正。同样明显的是，人类在影响许多具有经济意义的孢子虫以及可能还有那些不太重要的孢子虫的分布和当前数量方面发挥了主要作用，而且进化扩张的速度比以前认为的要快得多。
