Devi Mia Prastika, Haryoso Elkana, Rais Emha Ilhami, Karuniawan Anggik, Yahya Minhajul Qowim, Richaud Aurélien, Wang John, Rockman Matthew V, Tarno Hagus, Félix Marie-Anne
Department of Pests and Disease, Faculty of Agriculture, University of Brawijaya, JL Veteran Malang, Malang, East Java 65145, Indonesia.
Institut de Biologie de l'École Normale Supérieure, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, École Normale Supérieure, Paris Sciences et Lettres, 46 rue d'Ulm, 75005 Paris, France.
bioRxiv. 2025 May 16:2025.05.14.653126. doi: 10.1101/2025.05.14.653126.
Given the interest in the biogeography and diversity of the genus, we established a collection of these nematodes from field surveys on four Indonesian islands. We isolated over 60 strains belonging to ten species. Five species were previously known from other locations: , which was predominant, , , and . The five other species are new, and we describe them here as , , , and . RNA sequence analysis of 1,861 orthologous genes placed all species from Indonesia in the group of species. Four of the new species belong to a subclade of species so far only found in an East Asia-Indo-Pacific world region. The fifth new species, , appears as the sister of the - pair, both also found in Indonesia. The present findings are thus consistent with diversification in the group having occurred in this world region. Crosses between closely related species showed counterexamples to Haldane's "rule": for two pairs of species, in one cross direction we only found hybrid males. In addition, we found a pair of species that could partially interbreed: (East Java) with . sp. 41 (Solomon islands), with the hybrid males in one cross direction being fertile. Such closesly related species pairs are good models for genetic studies of incompatibilities arising during speciation.
鉴于对该属生物地理学和多样性的关注，我们通过对印度尼西亚四个岛屿的实地调查建立了这些线虫的一个集合。我们分离出了属于十个物种的60多个菌株。五个物种先前在其他地方已知：占主导地位的 ， ， ， 以及 。另外五个物种是新物种，我们在此将它们描述为 ， ， ， 以及 。对1861个直系同源基因的RNA序列分析将来自印度尼西亚的所有物种归入 物种组。四个新物种属于一个亚分支，该亚分支的物种迄今为止仅在东亚 - 印度 - 太平洋世界区域发现。第五个新物种 ，表现为 对的姐妹种，二者也都在印度尼西亚发现。因此，目前的研究结果与该世界区域发生的 组多样化一致。亲缘关系密切的物种之间的杂交显示出对霍尔丹“法则”的反例：对于两对物种，在一个杂交方向上我们只发现了杂交雄性。此外，我们发现了一对可以部分杂交的物种： （东爪哇）与 物种41（所罗门群岛），其中一个杂交方向上的杂交雄性是可育的。这种亲缘关系密切的物种对是研究物种形成过程中出现的不相容性的良好遗传模型。
