Euura viduata PR.

291 Euura viduata (Zetterstedt, 1838) Figs 306, 522–523 Tenthredo viduata Zetterstedt, 1838: 351. Lectotype designated below. Nematus striatipes Hartig, 1840: 26. Lectotype designated below. Syn. nov. Nematus lepidotus Hartig, 1840: 26. Lectotype designated below. Synonymy by Konow (1905b). Nematus palliceps Hartig, 1840: 25. Lectotype designated below. Syn. nov. Nematus brachyotus Förster, 1854a: 295–297. Syntypes ♀♀ (ZSM), not located. Type locality: Germany, Aachen area. Synonymy by Konow (1905b). Nematus luctuosus Förster, 1854a: 342–344. Syntypes ♀♀ (ZSM), not located. Type locality: Germany, Aachen area. Synonymy by Konow (1895). Nematus notatus Förster, 1854a: 298–299. Lectotype designated below. Synonymy by Lindqvist (1941b). Nematus vagus Zaddach, 1883 in Brischke 1883: 186–187. Syntypes ♀ ♂, probably destroyed (Blank & Taeger 1998). Type localities: Russia, Kaliningrad [Königsberg]; Poland, Gdansk [Danzig]; Finland; Silesia. Synonymy by Konow (1895). Secondary homonym of Tenthredo vaga Fabricius, 1781 [Euura vaga]. Amauronematus viduatus var. lugens Enslin, 1915: 379. Syntypes ♀♀, not located. Type locality: not stated. Synonymy by Muche (1975). Amauronematus viduatus var. laetus Enslin, 1915: 379. Lectotype designated below. Synonymy by Muche (1975). Amauronematus (Brachycoluma) spaethi Liston, 2005: 272–273. Syn. nov. Diagnosis Smooth mesepisternum, at least slightly pale pronotum, hypopygium, valvifer 2, and tergum 9, pale cerci, distinctly curved lancet with 20–24 annuli and basal two annuli with rudiments of serrulae enable identification of the females. The distinctive penis valve (somewhat rectangular paravalva, large broad valvispina, distinct invagination between valvispina and ventroapical lobe of paravalva) enables reliable identification of males. The penis valve of one male (DEI-GISHym31865, Fig. 524) differs only in lacking an invagination between the valvispina and the ventroapical lobe of the paravalva. Although this specimen might represent an additional species occurring in the Alps, associated females do not seem to be morphologically distinguishable from E. viduata, nor is there a clear genetic difference. Female 4.5–6.5 mm. Head black to extensively pale around eyes; labrum pale; clypeus black to pale; supraclypeal area black to pale; antenna black; thorax black to extensively pale laterally and slightly pale dorsally; pronotum slightly to extensively pale posteriorly; tegula black to pale; pterostigma centrally paler than externally; metafemur black to pale; metatibia pale or brown; hind tarsus black or brown; abdomen mostly black to extensively pale apically, but at least hypopygium, valvifer 2 and tergum 9 slightly pale; valvula 3 black to slightly pale basally; cerci pale; mesepisternum smooth; valvula 3 of medium length, in dorsal view gradually narrowing to an acute tip. Male 4–5 mm. Head black or slightly brown around eyes; labrum black to pale; clypeus black to pale; supraclypeal area black; antenna black; thorax black; pronotum black to extensively pale; tegula black to extensively pale; pterostigma brown, sometimes centrally paler than externally; metafemur black to extensively pale; metatibia pale or brown; hind tarsus black or brown; abdomen black; sternum 9 brown or pale; mesepisternum smooth; projection of tergum 8 medium-sized. Nematus palliceps has until now mostly been placed as a synonym of Euura clitellata (Serville, 1823), e.g., by Lacourt (1999), and Taeger et al. (2010). The lectotype of N. palliceps does not disagree with the extremely brief characterisation by Hartig (1840), and bears an original cabinet label by Hartig “ palliceps ”. Confusingly, this specimen also bears determination labels by O. Conde and A. Saarinen as respectively Nematus pallicercus Hartig, 1837 and Amauronematus pallicercus (Hartig, 1837). Nematus pallicercus was treated by Konow (1905b) as a synonym of Amauronematus fallax auct. nec Lepeletier, 1823 [i.e., as a species of the Euura histrio species group], and more recently sometimes as the name of a valid species of Amauronematus, e.g., by Taeger et al. (2010). Hartig (1837) stated that the two female syntypes of N. pallicercus have a body length equivalent to that of “the preceding species” [Nematus miniatus], which is given as 3.5 lines [approximately 7.9 mm]. This is significantly larger than the 6.2 mm body length of the lectotype of N. palliceps. Neither does the colour of the abdomen of pallicercus described by Hartig fit the palliceps lectotype [translated from German]: “the dorsum of the abdomen, which is reddish-edged on the sides, is blackish rusty-brown, only the first segment is deep black” [palliceps lectotype: terga 1–8 uniformly deep black, except for their pale ventral margins]. We conclude that no type specimen of N. pallicercus exists, and because it is not possible to identify it from the description as belonging to a currently recognised taxon, that it should be treated as a species incertae sedis. Type material examined Lectotype Tenthredo viduata, here designated SWEDEN – Norrbotten • ♀; Kengis Bruk; 67.192° N, 23.506° E; MZLU, MZLU2017260. Notes The slide preparation PR.721 VV was not located. Lectotype Nematus striatipes, here designated GERMANY • ♂; northern Germany [according to Hartig 1840: 22]; ZSM, DEI-GISHym12545. Lectotype Nematus lepidotus, here designated GERMANY • ♂; northern Germany [according to Hartig 1840: 22]; ZSM, DEI-GISHym12544. Lectotype Nematus palliceps, here designated GERMANY • ♀; northern Germany [according to Hartig 1840: 22]; ZSM, GBIF-GISHym3054. Lectotype Nematus notatus, here designated GERMANY – Nordrhein-Westfalen • ♀; Aachen area; 50.77° N, 6.09° E; ZSM, GBIF-GISHym3059. Lectotype Amauronematus viduatus var. laetus, here designated GERMANY – Nordrhein-Westfalen • ♀; Crefeld [Krefeld]; Ulbricht leg.; 51.34° N, 6.58° E; SDEI, GBIF-GISHym4105. Holotype Amauronematus (Brachycoluma) spaethi FRANCE – Corsica • ♀; SW Porto Vecchio, Tamaricciu Valley; 41.57° N, 9.24° E; 20 m a.s.l.; 7 Apr. 2004; J. Späth leg.; reared ex larva on Salix atrocinerea; SDEI, GBIF-GISHym4104. Host plants A wide spectrum of Salix spp. (Taeger et al. 1998; Macek et al. 2020). Genetics COI Based on 29 specimens, maximum within-species distance is 6.09% and the nearest neighbour, diverging by a minimum of 1.82%, is Euura erecta. Nuclear Based on 24 specimens, maximum within-species distance is 1% (0.93% based on haplotypes of individual females). The nearest neighbour, diverging by a minimum of 0.32%, is Euura viduata group specimen DEI-GISHym31865. Distribution and material examined Palaearctic. Specimens studied are from Finland, France, Germany, Italy, Morocco, Norway, Sweden, Switzerland, and the United Kingdom.