A revision of the Philoliche aethiopica species complex (Diptera: Tabanidae)

The Philoliche aethiopica (Thunberg) species complex has a history of being taxonomically difficult. This group of pollinating flies is of particular interest to botanists and pollination biologists. This paper reviews its taxonomy and redescribes its species with the aid of new morphological and molecular data. Molecular evidence supports the group’s monophyly, with two sister-clades, the “aethiopica” clade (= P. aethiopica) and the “rondani” clade (= P. elegans (Bigot), P. rondani (Bertoloni), P. rubiginosa Dias, and P. umbratipennis (Ricardo) stat. rev.). These clades correspond to two species groups defined by male morphology (“aethiopica” group = P. aethiopica and P. formosa (Austen); “rondani” group = P. elegans, P. rondani, P. rubiginosa, and P. umbratipennis stat. rev.). Molecular evidence also reveals a new character, the index of frons divergence, which is diagnostic for the two clades, and is thus a tool for separating previously indistinguishable females of P. aethiopica from P. rondani. Additionally, I show that some of the longest proboscid specimens, previously confused with P. rondani and P. aethiopica, are actually P. umbratipennis (Ricardo) stat. rev. P. rubiginosa, previously known only from Mozambique, is shown to occur in South Africa, and the male of this species is described for the first time. Furthermore, I show that the distribution of morphotypes within species with differing proboscis lengths is geographically structured, with long-proboscid species occurring only in the Albany Centre of Endemism.

Ethiopic Philoliche (Thunberg) 物种复合群在分类学上一直具有复杂性。这一群类群授粉蝇对于植物学家和授粉生物学家尤为关注。本文回顾了其分类学，并借助新的形态学和分子数据重新描述了其物种。分子证据支持该群的单系性，存在两个姐妹群，即“aethiopica”群（即 P. aethiopica）和“rondani”群（即 P. elegans (Bigot), P. rondani (Bertoloni), P. rubiginosa Dias, 以及 P. umbratipennis (Ricardo) stat. rev.）。这两个群与由雄性形态特征定义的两个物种群相对应（“aethiopica”群 = P. aethiopica 和 P. formosa (Austen)；“rondani”群 = P. elegans, P. rondani, P. rubiginosa 以及 P. umbratipennis stat. rev.）。分子证据还揭示了一个新的特征，即额指数分化指标，该指标对于两个群是诊断性的，因此是区分之前难以区分的 P. aethiopica 雌性个体与 P. rondani 的新工具。此外，我展示了部分最长的喙标本，之前曾被误认为是 P. rondani 和 P. aethiopica，实际上是 P. umbratipennis (Ricardo) stat. rev.。之前仅知于莫桑比克的 P. rubiginosa，现发现在南非也有分布，并且该物种的雄性个体首次被描述。此外，我还展示了不同喙长度的物种中形态型的分布具有地理结构，长喙物种仅存在于阿尔巴尼特有中心。