The nominal genus Tasactes Faust, 1894, consisting of two originally included nominal species from Myanmar, is rediscovered for the first time since being erected. Adult weevils herein assigned to the taxonomically re-defined Tasactes were abundant in forest floor litter at five localities in China (Yunnan and Sichuan), plus one specimen is available from Shaanxi and three from Nepal. Phylogenetic analysis of a 2,275 bp matrix concatenated from one mitochondrial (COI) and two nuclear markers (ITS2 and 28S) revealed that the monophyletic Tasactes consists of eight evolutionary significant terminal clades, either allopatric (three) or sympatric (two on Cang Shan in Yunnan and three on Mount Emei in Sichuan). The genus Tasactes is nested within the monophyletic Stromboscerini, while the tribe is sister to monophyletic Dryophthorus. The two morphological diagnostic characters of Tasactes, which are unique within the tribe, are the transversely truncated antennal club and conically projecting velvety apex of the club. So defined, Tasactes renders the genus Orthosinus paraphyletic. Considering the taxonomic neglect and uncertainties surrounding nominal Stromboscerini, all herein reported members of this tribe, including the Tasactes, are not assigned to Linnaean species. This paper illustrates the "clogging taxonomy" phenomenon, in which obscure historical names render taxonomic assignment of newly sampled specimens precarious. All the data used herein (localities, sequences, specimen images) are available online in public datasets dx.doi.org/10.5883/DS-TASACT1 and dx.doi.org/10.5883/DS-TASACT2., Vasily V. Grebennikov., and Obsahuje bibliografii
We report results of a faunal survey of Aradidae flat bugs sampled by sifting litter in 14 wet and discrete Tanzanian primary forests (= Tanzanian Forest Archipelago, TFA) of different geological origins and ages. Images, locality data and, when available, DNA barcoding sequences of 300 Aradidae adults and nymphs forming the core of the herein analyzed data are publicly available online at dx.doi.org/10.5883/DS-ARADTZ. Three Aradidae subfamilies and seven genera were recorded: Aneurinae (Paraneurus), Carventinae (Dundocoris) and Mezirinae (Afropictinus, Embuana, Linnavuoriessa, Neochelonoderus, Usumbaraia); the two latter subfamilies were also represented by specimens not assignable to nominal genera. Barring the six nominal species of Neochelonoderus and Afropictinus described earlier by us from these samples and representing 11 of the herein defined Operational Taxonomic Units (OTU), only one of the remaining 52 OTUs could be assigned to a named species; the remaining 51 OTUs (81%) represent unnamed species. Average diversity of Aradidae is 4.64 species per locality; diversity on the three geologically young volcanoes (Mts Hanang, Meru, Kilimanjaro) is significantly lower (1.33) than on the nine Eastern Arc Mountains (5.67) and in two lowland forests (5). Observed phylogeographic structure of Aradidae in TFA can be attributed to vicariance, while the depauperate fauna of Aradidae on geologically young Tanzanian volcanoes was likely formed anew by colonisation from nearby and geologically older forests., Vasily V. Grebennikov, Ernst Heiss., and Obsahuje bibliografii