Galoyan Eduard, Nazarov Roman, Altmanová Marie, Matveevsky Sergey, Kropachev Ivan, Dedukh Dmitrij, Iryshkov Eugene, Pankin Mark, Sopilko Natalia, Nikolaev Oleg, Orlov Nikolai, Arakelyan Marine, Klíma Jiří, Solovyeva Evgeniya, Nguyen Tao, Kratochvíl Lukáš
Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, Leninsky Prospect 33, Moscow, Russia.
Zoological Museum of Moscow State University, B. Nikitskaya ul. 2, Moscow, 125009, Russia.
Sci Rep. 2025 Jan 24;15(1):3094. doi: 10.1038/s41598-024-83300-y.
Obligatory parthenogenesis in vertebrates is restricted to squamate reptiles and evolved through hybridisation. Parthenogens can hybridise with sexual species, resulting in individuals with increased ploidy levels. We describe two successive hybridisations of the parthenogenetic butterfly lizards (genus Leiolepis) in Vietnam with a parental sexual species. Contrary to previous proposals, we document that parthenogenetic L. guentherpetersi has mitochondrial DNA and two haploid sets from L. guttata and one from L. reevesii, suggesting that it is the result of a backcross of a parthenogenetic L. guttata × L. reevesii hybrid with a L. guttata male increasing ploidy from 2n to 3n. Within the range of L. guentherpetersi, we found an adult tetraploid male with three L. guttata and one L. reevesii haploid genomes. It probably originated from fertilisation of an unreduced triploid L. guentherpetersi egg by a L. guttata sperm. Although its external morphology resembles that of the maternal species, it possessed exceptionally large erythrocytes and was likely sterile. As increased ploidy level above triploidy or tetraploidy appears to be harmful for amniotes, all-female asexual lineages should evolve a strategy to prevent incorporation of other haploid genomes from a sexual species by avoiding fertilisation by sexual males.
脊椎动物中的专性孤雌生殖仅限于有鳞目爬行动物，且是通过杂交进化而来的。孤雌生殖体可与有性生殖物种杂交，从而产生倍性水平增加的个体。我们描述了越南孤雌生殖的蝴蝶蜥（Leiolepis属）与一个亲本有性生殖物种的两次连续杂交。与之前的观点相反，我们记录到孤雌生殖的冈氏蝴蝶蜥（Leiolepis guentherpetersi）具有来自网纹蝴蝶蜥（L. guttata）的线粒体DNA和两个单倍体组以及来自丽纹蝴蝶蜥（L. reevesii）的一个单倍体组，这表明它是孤雌生殖的网纹蝴蝶蜥×丽纹蝴蝶蜥杂交后代与一只网纹蝴蝶蜥雄性回交的结果，使倍性从2n增加到3n。在冈氏蝴蝶蜥的分布范围内，我们发现了一只成年四倍体雄性，它具有三个网纹蝴蝶蜥和一个丽纹蝴蝶蜥的单倍体基因组。它可能起源于一个未减数的三倍体冈氏蝴蝶蜥卵被一个网纹蝴蝶蜥精子受精。尽管它的外部形态与母本物种相似，但它拥有异常大的红细胞，且可能不育。由于三倍体或四倍体以上的倍性增加似乎对羊膜动物有害，全雌性无性系应该进化出一种策略，通过避免被有性生殖雄性受精来防止纳入来自有性生殖物种的其他单倍体基因组。
