Becnel J
USDA/ARS Medical and Veterinary Entomology Research Laboratory, Gainesville, Florida.
Folia Parasitol (Praha). 1994;41(2):91-6.
Heterosporous (polymorphic) microsporidia in mosquitoes are characterized by intricate life cycles involving multiple spore types responsible for horizontal (per os) and vertical (transovarial) transmission. They affect two generations of the mosquito and some involve an obligate intermediate host. Heterosporous microsporidia are generally very host and tissue specific with complex developmental sequences comprised of unique stages and events. Full details on the intricate relationships between heterosporous microsporidia and their mosquito hosts have only recently been elucidated. Edhazardia aedis (Kudo, 1930) and Culicospora magna (Kudo, 1920) have developmental sequences in larvae that involve gametogony followed by plasmogamy and nuclear association to form diplokarya. These diplokaryotic stages then undergo karyogamy and form binucleate spores responsible for transovarial transmission. In the filial generation, haplosis occurs as a result of nuclear dissociation to produce uninucleate spores infectious to larval mosquitoes. Amblyospora californica (Kellen et Lipa, 1960) has similar sequences except that haplosis is by meiosis to produce spores infectious for a copepod intermediate host. A third spore type is formed in the intermediate host responsible for infection in a new generation of the mosquito host.
蚊子体内的异孢（多态）微孢子虫的特点是具有复杂的生命周期，涉及多种孢子类型，分别负责水平（经口）和垂直（经卵）传播。它们影响两代蚊子，有些还涉及一个专性中间宿主。异孢微孢子虫通常具有很强的宿主和组织特异性，其复杂的发育序列由独特的阶段和事件组成。关于异孢微孢子虫与其蚊子宿主之间复杂关系的全部细节直到最近才得以阐明。伊蚊埃氏微孢子虫（库多，1930年）和大型库利科斯孢虫（库多，1920年）在幼虫中的发育序列包括配子发生，随后是质配和核结合形成双核体。这些双核阶段随后进行核配并形成负责经卵传播的双核孢子。在子代中，由于核解离发生单倍体化，产生对幼虫蚊子具有感染性的单核孢子。加利福尼亚安布利孢虫（凯伦和利帕，1960年）有类似的序列，只是单倍体化是通过减数分裂产生对桡足类中间宿主具有感染性的孢子。在中间宿主中形成第三种孢子类型，负责感染新一代的蚊子宿主。
