Kearn Graham C, Whittington Ian D, Euzet Louis
School of Biological Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK.
Folia Parasitol (Praha). 2006 Mar;53(1):57-62. doi: 10.14411/fp.2006.005.
The elongated encased spermatophores of the capsalid (entobdelline) monogeneans Neoentobdella diadema (Monticelli, 1902) Kearn et Whittington, 2005 and N. apiocolpos (Euzet et Maillard, 1967) Kearn et Whittington, 2005 have been found attached by their proximal ends to the region of the vaginal opening, with the bulk of the spermatophore projecting from the vagina and therefore lying outside the body. In spite of previous reports, no spermatophores were found projecting from the common genital opening and if spermatophore exchange is as rapid as it is in the related entobdelline Entobdella soleae, then the chances of finding a spermatophore in this location are small. In N. diadema and N. apiocolpos it is likely that sperm enters the vagina through the open proximal end of an attached spermatophore, after which the empty spermatophore case is probably discarded. There is no evidence for a previous proposal that the whole spermatophore is engulfed by the vagina followed by digestion of the case to release the sperm. Three specimens of N. diadema were found each with two spermatophore cases projecting from the vagina and a specimen of N. apiocolpos carried three cases. Assuming that each parasite is able to donate or receive only one spermatophore at each mating, then the presence of one spermatophore does not prevent a further mating and acceptance of a fresh spermatophore. In spite of differences between the spermatophores of E. soleae and N. diadema/N. apiocolpos, the events of spermatophore exchange may be similar.
已发现冠盘虫科（内盘虫类）单殖吸虫新冕盘虫（Neoentobdella diadema）（蒙蒂切利，1902年）卡恩和惠廷顿，2005年及蜂房新冕盘虫（N. apiocolpos）（厄泽和马亚尔，1967年）卡恩和惠廷顿，2005年细长的包被精荚，其近端附着于阴道口区域，精荚大部分从阴道伸出，因此位于体外。尽管有先前的报道，但未发现精荚从共同生殖孔伸出，并且如果精荚交换像在相关的内盘虫类的鳎内盘虫（Entobdella soleae）中那样迅速，那么在这个位置找到精荚的机会很小。在新冕盘虫和蜂房新冕盘虫中，精子可能通过附着的精荚开放的近端进入阴道，之后空的精荚壳可能被丢弃。没有证据支持先前的提议，即整个精荚被阴道吞噬，随后精荚壳被消化以释放精子。发现三只新冕盘虫标本，每只都有两个精荚壳从阴道伸出，一只蜂房新冕盘虫标本带有三个精荚壳。假设每个寄生虫在每次交配时只能捐赠或接受一个精荚，那么存在一个精荚并不妨碍进一步交配和接受一个新的精荚。尽管鳎内盘虫与新冕盘虫/蜂房新冕盘虫的精荚存在差异，但精荚交换的过程可能相似。
