Reevaluation of species richness in Winnertzia (Diptera, Cecidomyiidae, Winnertziinae), with descriptions of 37 new species from Sweden, Peru and Australia Author Jaschhof, Mathias 0000-0003-3447-1620 Author Jaschhof, Catrin 0000-0002-1030-0934 mjaschhof@yahoo.de text Zootaxa 2020 2020-08-11 4829 1 1 72 journal article 8695 10.11646/zootaxa.4829.1.1 04b19d7f-1d74-41ec-b657-9b57f47826f9 1175-5326 4402757 7B34E058-03B4-44D0-AC4E-065B010172E1 Winnertzia solidaginis group Diagnosis. Morphological structures occurring exclusively in the solidaginis group are unknown. Species classified in this group fulfil two criteria: their morphology does not match the definitions of other subdivisions of Winnertzia , and their aedeagal bulge is covered with fine, spike-shaped microtrichia in longitudinal lines. The counterpart of the solidaginis group is the tridens group, in which the aedeagal bulge is covered with small, randomly distributed knobs. Phylogeny. The solidaginis group as delineated here is basically a catch-all category for Winnertzia whose morphology is incompatible with other groups. Even so, many of the species accomodated here share overall similarity to a considerable extent, suggesting that this is not an entirely arbitrary assemblage. The core of the group, made up of W. solidaginis agg. and several species closely related to it, is likely to be monophyletic. Male morphology indicates that there are other monophyletic subgroups, such as the species complexes around W. bulbifera , W. longiptera , and W. nigripennis , each distinguished by several characters in combination, rather than by a singular feature. The fact that the same characters occur in more than one subgroup, although in different combinations, makes phylogenetically conclusive character patterns difficult to identify. Therefore, it seems probable that the interspecific relationships within the solidaginis group cannot be resolved using solely male morphological indicators. Species included. Most Winnertzia we have seen, in Sweden and elsewhere, are members of the solidaginis group, a fact suggesting that this applies to the bulk of the species named in the past also. Of the Winnertzia species described by the late B.M. Mamaev, 32 turned out to belong to the solidaginis group ( Jaschhof & Jaschhof 2013: 85 ). None of these species can be recognized from published descriptions, and some are likely identical with species in Sweden left unnamed here. Species of the solidaginis group whose presence in Sweden is proven are W. brevipalpata Jaschhof , W. curvata Panelius , W. fusca Kieffer , W. graduata Spungis , W. longiptera Mamaev , W. nigra Mamaev , W. padicola Spungis , W. parvispina Jaschhof , and W. pinicola Kieffer. Another three Winnertzi a previously reported as occurring in Sweden ( Jaschhof & Jaschhof 2013 ) are revealed here as aggregate species: W. bulbifera Mamaev (comprising the genuine W. bulbifera and two apparently unnamed species), W. nigripennis Kieffer (comprising the genuine W. nigripennis , a previously unnamed species described here as W. ombergensis , and three species in which we cannot decide whether they are unnamed or unrecognizable from the literature), and W. solidaginis Felt (comprising four genetically distinct species). Of 30 species in our material that we cannot relate to available names (not counted those subsumed under W. solidaginis ), 11 are described here as new to science.