Ovoviviparity in the tropical earwig species Spongovostox semiflavus (Dermaptera: Spongiphoridae), with potential convergent elongation of male genitalia
Ovoviviparity in the tropical earwig species Spongovostox semiflavus (Dermaptera: Spongiphoridae), with potential convergent elongation of male genitalia
复制标题
热带蠼螋物种 Spongovostox semiflavus（皮翅目：Spongiphoridae）的卵胎生，具有潜在的雄性生殖器会聚伸长的能力
DOI：
10.1093/aesa/saw071
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发表时间：
2017
影响因子：
2.3
通讯作者：
C.-Y.
中科院分区：
文献类型：
--
作者：
Kamimura;Y.;Lee;C.-Y.
卵生和胎生在动物中独立进化了多次。尽管雌土蠼螋对其卵表现出广泛的亲代照顾，但据报道，只有少数几种自由生活的非动物土蠼螋能够产卵。相比之下，迄今为止，所有研究的以哺乳动物为食的Arixeniidae科和hemimiidae科成员都是胎生的。本文报道了一种名为Spongovostox semiflavus（Bormans, 1894）的热带土蜈蚣的卵生现象（forficu总目：海绵蚓科：海绵蚓科）。我们观察到该物种的雌性在卵巢内保留了发育良好的胚胎，然后在孵化前将完整的卵包膜产下。一个女性体内平均有9.4个胚胎同时发育。在海绵亚科的另一个物种marava arachidis（Yarsin, 1860）中也报道过类似的情况。没有额外的交配，Spo。半黄的雌性在14-27天的时间里至少产三窝，平均9窝。semiflavusandM。蜘蛛雄性的特征是细长的男性生殖器，长度是身体长度的两倍多。有趣的是，在其他两种被报道过的（卵）胎生的海绵类动物中也存在伸长的雄性生殖器。我们讨论了男性生殖结构的进化和女性（卵）胎生发育的潜在趋同的原因。
Ovoviviparity and viviparity have evolved independently multiple times in animals. Although females exhibit extensive parental care of their eggs, (ovo)viviparity has only been reported in a few species of free-living, nonepizoic earwigs. In contrast, to date, all the studied members of families Arixeniidae and Hemimeridae, which live on mammals, are viviparous. We herein report ovoviviparity in the tropical earwig species,Spongovostox semiflavus(Bormans, 1894) (Forficuloidea: Spongiphoridae: Spongiphorinae). We observed that females of this species retain well-developed embryos within the ovaries and then lay them with complete egg envelopes just before hatching. An average of 9.4 embryos concurrently developed in a female’s body. A similar condition has been reported for only one other speciesMarava arachidis(Yarsin, 1860), in the subfamily Spongiphorinae. Without additional mating,Spo. semiflavusfemales produced at least three clutches, consisting of an average of nine offspring within a period of 14–27 d. BothSpo. semiflavusandM. arachidismales are characterized by elongated male genitalia that are more than twice as long as their body lengths. Interestingly, elongated male genitalia are also present in the two other spongiphorids for which (ovo)viviparity has been reported. We discuss the causes of the potential convergence of the evolution of the male genital structure and the development of (ovo)viviparity in females.