Winnertzia pinicola Kieffer, 1913

Jaschhof, Mathias & Jaschhof, Catrin, 2020, Reevaluation of species richness in Winnertzia (Diptera, Cecidomyiidae, Winnertziinae), with descriptions of 37 new species from Sweden, Peru and Australia, Zootaxa 4829 (1), pp. 1-72 : 40-41

Winnertzia pinicola Kieffer

Diagnosis. A medium-sized, brown Winnertzia , whose male genitalic structures ( Jaschhof & Jaschhof 2013: fig. 40A–B) provide the best characters for distinguishing it from both W. nigripennis and W. solidaginis agg. Most importantly, the gonostylus of W. pinicola is very gently tapered from the broad base towards the apex, the latter bearing the comparatively narrow pectinate claw. Furthermore, of the gonocoxal synsclerite, the ventroanterior edge is broadly rounded, the ventral emargination is U shaped, with a moderately large membranous area basally, and the dorsal apodemes are fairly long; the posterior edge of the ninth tergite, which is comparatively narrow, has a fairly deep, wide concavity medially; and the aedeagal apodeme has often, but not always, a slight broadening apically that is faintly reminiscent of an anchor-shape. As a non-genitalic distinction, the empodia are as long as the claws. See also W. acutistylus , a new species described below to have an apically constricted gonostylus.

Discussion. The material we studied contains a few specimens (GULI000020965, GULI000020967 and CEC3270–CEC3273) that, although closely resembling W. pinicola , do not perfectly match the diagnosis given above. We deem it possible that they belong to one or more sibling species. One of the characters found to vary is the vestiture on the aedeagal bulge, which in some specimens is considerably denser than in others, and, especially at the base of the bulge, resembling knobs rather than spike-shaped microtrichia. It is obvious that W. pinicola will need further attention by taxonomists, and that revisional work in the future should consider to designate a neotype for this species once the delineation problems are satisfyingly resolved.

Distribution in Sweden. All but one of the 48 specimens we studied of W. pinicola were collected in the southern half of Sweden, the northernmost distribution being Uppland. Our only specimen from northern Sweden is from Västerbotten.

Material studied. Specimens listed by Jaschhof & Jaschhof (2013) and as follows. Sweden: 4 males, Skåne, Limhamns kalkbrott, 27 July–16 August 2009, MT , B.W. Svensson et al. (spns CEC2966 – CEC2969 ); 1 male, Små- land, Nybro, Bäckebo, Grytsjön NR, thin aspen forest, 9 April–14 May 2015, MT, MCJ (spn CEC2970 ) ; 1 male, same data but swampy meadow at forest edge, 17 June–16 July 2015 (spn CEC2971 ); 4 males, Öland, Borgholm, Rönnerum-Abbantorp NR, mixed broadleaf forest, 16 July–21 August 2016, MT, MCJ (spns CEC2973 – CEC2974 , CEC2985 – CEC2986 ) ; 1 male, Borgholm, Lindreservat NR, mixed broadleaf forest, 11 June–21 July 2015, MT, MCJ (spn CEC2989 ) ; 3 males, same data but 22 July–23 August 2015 (spns CEC2982 – CEC2984 ); 1 male, Borgholm, Skepparsäng NR, mixed broadleaf forest, 11 June–21 July 2015, MT, MCJ (spn CEC2976 ) ; 1 male, Öland, Mörbylånga, Färjestaden, backyard with birch grove, 11 July–18 August 2015, MT, MCJ (spn CEC2990 ) ; 1 male, Mörbylånga, Västerstad elm-forest NR, old-growth elm forest, 10 June–9 July 2014, MT, SMTP (trap 3002, col- lection event 3053) (spn CEC2975 ) ; 1 male, Mörbylånga, Skogsby, Station Linné, swampy meadow, 2 June–4 July 2016, MT, MCJ & E. Gustavsson (spn CEC2993 ); 1 male, Mörbylånga, Skogsby lund NR, mixed broadleaf forest, 18 August–22 September 2015, MT, MCJ (spn CEC2991 ) (all in SDEI).