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.埃塞俄比亚长喙虻（Philoliche aethiopica, Thunberg）复合类群长期以来均为分类学上的疑难类群。该类传粉蝇类群深受植物学家与传粉生物学研究者的关注。本文综述了该类群的分类学研究历史，并结合全新的形态学与分子生物学数据对其物种进行了重新描述。分子证据支持该类群具有单系性（monophyly），可划分为两个姊妹支系（sister-clades）："aethiopica支"（=埃塞俄比亚长喙虻P. aethiopica）与"rondani支"（=优雅长喙虻P. elegans (Bigot)、隆丹长喙虻P. rondani (Bertoloni)、锈色长喙虻P. rubiginosa Dias以及暗翅长喙虻P. umbratipennis (Ricardo) stat. rev.）。上述两支系分别对应依据雄性形态特征界定的两个物种组："aethiopica组"（=埃塞俄比亚长喙虻P. aethiopica与华美长喙虻P. formosa (Austen)）；"rondani组"（=优雅长喙虻P. elegans、隆丹长喙虻P. rondani、锈色长喙虻P. rubiginosa以及暗翅长喙虻P. umbratipennis stat. rev.）。分子证据还揭示了一项全新的鉴别特征——额宽分歧指数（index of frons divergence），该特征可作为两个姊妹支系的鉴别依据，从而能够区分此前难以鉴别的埃塞俄比亚长喙虻与隆丹长喙虻的雌性个体。此外，本文发现部分此前被误定为隆丹长喙虻与埃塞俄比亚长喙虻的超长口器标本，实际上应为暗翅长喙虻P. umbratipennis (Ricardo) stat. rev.。此前仅记录分布于莫桑比克的锈色长喙虻P. rubiginosa，本次研究证实其在南非亦有分布，并首次对该物种的雄性个体进行了形态描述。进一步研究发现，不同口器长度物种的形态型分布具有显著地理格局：长口器物种仅分布于阿尔巴尼特有物种中心（Albany Centre of Endemism）。