Ruiz A, Heed W B, Wasserman M
Departamento de Genética y Microbiología, Universidad Autónoma de Barcelona, Spain.
J Hered. 1990 Jan-Feb;81(1):30-42. doi: 10.1093/oxfordjournals.jhered.a110922.
The mojavensis cluster of the repleta species group of Drosophila (Drosophilidae: Diptera) consists of three species. One is newly described as D. navojoa. A second species, described here as D. arizonae, replaces D. arizonensis, which has become a junior subjective synonym for D. mojavensis, the third species in the cluster. A phylogeny of the three species is presented, based on chromosomal inversions, morphology, and the ability to produce hybrids. Breakage points are assigned for all inversions, and male genitalia are figured; 186 crosses were made from 225 possible combinations among 15 geographic strains from the southwestern United States, Mexico, and Guatemala. It is confirmed that D. mojavensis and D. arizonae are very closely related and shown that D. navojoa is more distantly related in regard to all criteria. This relationship is supported by the geographical positions of the ancestral gene sequences in each species, which show a sequential northwest movement (D. navojoa----D. arizonae----D. mojavensis) from southern Mexico to southern California and northern Arizona. The relationship is also supported by the fact that D. navojoa breeds in Opuntia cactus, an ancestral behavior, whereas the other two species breed chiefly in Stenocereus cacti, a derived behavior. The possible role of this host plant shift in speciation is discussed.
果蝇（果蝇科：双翅目）的repleta物种组中的mojavensis集群由三个物种组成。其中一个新描述为纳沃亚果蝇（D. navojoa）。第二个物种，这里描述为亚利桑那果蝇（D. arizonae），取代了亚利桑那果蝇（D. arizonensis），后者已成为该集群中第三个物种莫哈韦果蝇（D. mojavensis）的次主观同物异名。基于染色体倒位、形态学以及产生杂种的能力，给出了这三个物种的系统发育。为所有倒位确定了断点，并绘制了雄性生殖器图；从美国西南部、墨西哥和危地马拉的15个地理菌株的225种可能组合中进行了186次杂交。证实了莫哈韦果蝇和亚利桑那果蝇密切相关，并表明就所有标准而言，纳沃亚果蝇的关系更远。每个物种中祖先基因序列的地理位置支持了这种关系，这些位置显示出从墨西哥南部到南加利福尼亚和亚利桑那北部的西北方向的连续移动（纳沃亚果蝇——亚利桑那果蝇——莫哈韦果蝇）。这种关系还得到以下事实的支持，即纳沃亚果蝇在仙人掌属仙人掌中繁殖，这是一种祖先行为，而其他两个物种主要在柱状仙人掌属仙人掌中繁殖，这是一种衍生行为。讨论了这种寄主植物转移在物种形成中的可能作用。
