Winnertzia fraxinophila, Jaschhof & Jaschhof, 2020

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 : 44-46

Winnertzia fraxinophila sp. nov.

Figs 77–79

Diagnosis. A medium-sized, brown Winnertzia , distinguished from other species of the solidaginis group by male genitalic characters, as follows ( Fig. 77 ). The massive gonostylus is markedly broadened apically (↓ 4); the apical claw is of moderate size; and the basolateral apophysis is small and only little angulated. Of the gonocoxal synsclerite, the ventroanterior edge is evenly, broadly rounded (↓ 5), the dorsoposterior portions protrude considerably beyond the ventroposterior portions (↓ 6), and the dorsal apodemes are long and thin. The ninth tergite is narrowed towards the posterior edge, which has a narrow, fairly deep notch medially (↓ 7). The aedeagal apodeme, which is parallel-sided for most of its length, has a weakly sclerotized, constricted apex. Females and preimaginal stages of W. fraxinophila are unknown. See W. bulbifera agg. for other species with inflated gonostylar apex. According to Mamaev’s (1963: fig. 3.6) original description and Spungis’s (1992: fig. 60) re-illustration, W. equestris resembles W. fraxinophila , but differs in at least the following characters: the gonostylus is nearly parallel-sided, the gonocoxal synsclerite lacks dorsoposterior protrusions, and the ninth tergite is more shallowly notched medially.

Other male characters. Body size 1.9–2.1 mm. Head. Eye bridge 3–4 ommatidia long dorsally. Antenna almost two thirds body length. Scape slightly larger than pedicel, both concolorous with flagellum. 12 flagellomeres, translucent sensilla on flagellomeres 1–11. Fourth flagellomere: neck 0.9 times as long as node; node 1.6 times as long as broad; sensory hairs numerous; translucent sensilla filiform, occasionally two-branched, lateral sensillum obliquely aligned, either variously bent or U-shaped ( Fig. 78 ), medial sensillum longitudinally aligned, varying in length ( Fig. 79 ). Palpus as long as head height, 4 setae-bearing segments; fourth segment longest of all. Labella of normal size. Thorax. Pronotal setae 10–14. Anepimeral setae absent. Lateral mediotergal microtrichia large. Parascutellar area bright, sharply contoured. Wing shorter than body, 2.6 times as long as broad. Costal cell slightly reinforced. M 4 long, almost straight, CuA moderately bent, both veins extending to edge of wing. Legs. Scales pointed. Basitarsal spines absent. Fore tibia 0.9 length T 2. Acropods: claws slightly bent, basal tooth large; empodia vestigial. Abdomen. Pleural membrane with setae and scales. Genitalia ( Fig. 77 ). Ninth tergite two thirds gonopodal length; setae confined to lateroposterior portions; posterior edge usually with darkly pigmented margin around notch; anterior edge straight, indistinct. Gonocoxal synsclerite broader than long; ventral emargination resembling a widely open U, with large unsclerotized portion basally. Gonostylus elongate, almost straight; pectinate claw with slight furrow along base. Aedeagal bulge with closely spaced rows of tiny spikes. Solid basal portion of aedeagal apodeme moderately long. Tegmen subtriangular with narrowly rounded apex, sharply contoured; flaps large, faintly contoured; parameral apodemes moderately large.

Etymology. The name means ash-loving, which refers to the habitat of the specimens available for our study.

Type material. Holotype. Male , Sweden, Öland , Mörbylånga , Skogsby lund Nature Reserve, mixed broadleaf forest with abundant dead ash trees, 15 July–17 August 2015, Malaise trap, M. & C. Jaschhof (spn CEC 3029 in NHRS) . Paratypes. 6 males, same data as the holotype (spns CEC3030 – CEC 3035 in NHRS) .

Other material studied. Sweden: 1 male, Öland, Mörbylånga, Stora Dalby lund NR, mixed broadleaf forest with abundant dead ash trees, 9 July–8 August 2015, MT, MCJ (spn CEC 3040 in SDEI) ; 3 males, same data but 9 August–3 October 2015 (spns CEC3036 – CEC 3038 in SDEI) ; 1 male, Öland, Borgholm, Skepparsäng NR, mixed coniferous / broadleaf forest, 22 July–23 August 2015, MT, MCJ (spn CEC 3039 in SDEI) .

Distribution and phenology. All the specimens known of W. fraxinophila were collected in summer 2015 on Öland, in forests heavily affected by the ash dieback disease.

Figures

FIGURES 74–79. Male morphology of Winnertzia egregia (74–76) and Winnertzia fraxinophila (77–79), holotypes. 74: Fourth flagellomere, lateral. 75: Ditto, medial. 76: Genitalia, ventral. 77: Ditto. 78: Fourth flagellomere, lateral. 79: Ditto, medial. Scales 0.05 mm. Arrows refer to characters described in the diagnoses.