We examined four suspected cases of facultative parthenogenesis in three species of a neotropical lineage of pitvipers of the Bothrops atrox group. Reproduction without mating was observed in captive females of B. atrox, B. moojeni and B. leucurus housed alone for seven years (the two former species) and nine years (the latter one). In addition to the observation of captivity data, we investigated molecularly this phenomenon using heterologous microsatellites. DNA was extracted from the mothers’ scales or liver, from embryo and newborn fragments, and yolked ova. Four of the microsatellites showed good amplification using Polymerase Chain Reaction and informative band segregation patterns among each mother and respective offspring. Captivity information, litter characteristics (comparison of the number of newborns, embryos and yolked ova) and molecular data altogether agreed with facultative parthenogenesis predictions in at least three out of the four mothers studied: B. atrox (ID#933) was heterozygous for three out of the four markers, and the sons S1 and S2 were homozygous; B. moojeni (BUT86) was heterozygous for two out of four markers, offspring S1, S3, E2, and E4, and O1 to O6 were homozygous; and B. leucurus (MJJS503) was heterozygous for three out of four markers, and son E1 and O1 were homozygous. B. moojeni (BUT44) was homozygous for all loci analyzed in the mother and offspring, which although not informative is also consistent with parthenogenesis. This study represents the first molecular confirmation of different pitviper species undergoing facultative parthenogenesis among Neotropical endemic snakes.

中文翻译：

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Bothrops atrox 组的三个新热带 pitviper 物种兼性孤雌生殖的证据

我们检查了在 Bothrops atrox 组的 pitvipers 的新热带谱系的三个物种中兼性孤雌生殖的四个疑似病例。在 B. atrox、B. moojeni 和 B. leucurus 的圈养雌性中观察到没有交配的繁殖，单独饲养 7 年（前两种）和 9 年（后一种）。除了观察圈养数据外，我们还使用异源微卫星对这种现象进行了分子研究。DNA 是从母亲的鳞片或肝脏、胚胎和新生儿碎片以及卵黄卵中提取的。四个微卫星使用聚合酶链反应和信息条带分离模式在每个母亲和各自的后代中显示出良好的扩增。圈养信息、垫料特征（新生儿数量的比较、胚胎和卵黄卵）和分子数据完全与所研究的四位母亲中至少三位的兼性孤雌生殖预测一致：B. atrox (ID#933) 对四个标记中的三个是杂合的，儿子 S1 和 S2 是纯合子；B. moojeni (BUT86) 对于四个标记中的两个是杂合的，后代 S1、S3、E2 和 E4，并且 O1 到 O6 是纯合的；B. leucurus (MJJS503) 对四个标记中的三个是杂合的，儿子 E1 和 O1 是纯合的。B. moojeni (BUT44) 对于在母体和后代中分析的所有基因座都是纯合的，虽然没有信息量，但也与孤雌生殖一致。这项研究代表了新热带特有蛇中经历兼性孤雌生殖的不同 pitviper 物种的首次分子确认。