Winnertzia tumidoides, 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 : 23-25

Winnertzia tumidoides sp. nov.

Figs 38–40

Diagnosis. An inconspicuous, medium-sized, brown Winnertzia , whose genitalia are generally similar to that of W. tumida (widespread in Northern Europe) and W. tamariciphila (from Uzbekistan). A structure diagnostic of these three species is the conspicuously long, almost straight gonostylus, whose apex (i.e. the portion above the pectinate claw) is parallel-sided. A peculiarity of W. tumidoides is that the gonostylar claw is situated, either entirely or for the greater part, at the distal half of the gonostylar body, so that the apex is relatively short ( Fig. 38 , ↓ 4). Another distinction is that the gonocoxal emargination, which is U- rather than V-shaped, has a reinforced, sclerotized base (↓ 5). Females and preimaginal stages of W. tumidoides are unknown.

Winnertzia tumida , of which we studied all the six males known from Sweden, differs from W. tumidoides in a number of characters, as follows. It is a slightly more robust and darker brown species; the fore tibia is somewhat longer (1.5 times as long as T 2); the empodia are longer (almost claw-long); the wings are broader (2.2 times as long as broad); the fourth flagellomere has a thicker node (1.5 times as long as broad) and a shorter neck (0.6 times as long as the node); and the number of pronotal setae is considerably larger (15–17). As for genitalic characters, the larger part of the pectinate claw is situated in the basal half of the gonostylus; the dorsoposterior portions of the gonocoxites are conspicuously inflated; and the gonocoxal emargination is smaller, V- rather than U-shaped, and unsclerotized basally ( Jaschhof & Jaschhof 2013: fig. 33). One of the two specimens from England, on which the original description of W. tumida is based, appears to have the gonostylar claw in a slightly more distal position compared with Swedish specimens ( Panelius 1965: fig. 34g), which indicates some intraspecific variation in this character. Winnertzia tamariciphila is distinguished from both W. tumida and W. tumidoides by the short, three-segmented palpus and the tarsal claws bearing three hair-like teeth ( Mamaev 1963: fig. 2.4).

Other male characters. Body size 1.8 mm. Head. Eye bridge 3–4 ommatidia long dorsally. Antenna slightly longer than half body. Scape and pedicel same size, both concolorous with flagellum. 11 flagellomeres, translucent sensilla on flagellomeres 1–10, long, filiform, mostly linear to slightly sinuous, others markedly bent or furcate. Fourth flagellomere: neck 0.8 times as long as node; node 1.8 times as long as broad; sensory hairs dense ( Figs 39–40 ). Palpus slightly shorter than head height, 4 setae-bearing segments, apical segment longest of all. Labella fully developed, albeit small. Thorax. Pronotal setae 6. Anepimeral setae absent. Lateral mediotergal microtrichia large. Parascutellar area inconspicuous. Wing slightly shorter than body, 2.6 times as long as broad. Costal cell slightly reinforced. M 4 long, nearly straight, CuA gently bent, both veins extending to edge of wing. Legs. Scales pointed. Basitarsal spines absent. Fore tibia 1.3 times length T 2. Acropods: claws slightly bent, empodia vestigial.

Abdomen. Pleural membrane setose. Genitalia ( Fig. 38 ). Ninth tergite shorter than half gonopodal length; setae confined to lateroposterior portions; posterior edge straight, slightly reinforced medially; anterior edge indistinct. Gonocoxal synsclerite slightly broader than long; a short portion ventrobasally non-setose; ventral emargination large; dorsoposterior portions not markedly inflated, narrowly rounded. Gonostylus 3.5 times as long as broad; pectinate claw obliquely aligned, situated somewhat dorsomedially on a small bulge; basolateral apophysis inconspicuous, not angulated. Aedeagal apodeme broadest beyond solid basal portion, the latter long, suddenly narrowed; distal portion gently tapered towards apex. Aedeagal bulge with closely spaced rows of tiny microtrichia. Tegmen largely membranous, only basally sharply contoured, slightly tapered towards broadly rounded apex; flaps distinct, reinforced and with fine microtrichia along edges; parameral apodemes moderately large.

Etymology. The name, an adjective meaning tumida -like, refers to the close resemblance of this species to W. tumida .

Type material. Holotype. Male , Sweden, Öland , Mörbylånga, Gamla Skogsby (Kalkstad), mixed broadleaf forest with plenty of dead ash trees, 3 June–4 July 2016, Malaise trap, M. & C. Jaschhof & E. Gustavsson (spn CEC 1833 in NHRS).

Other material studied. Sweden: 1 male (only genitalia slide-mounted), Öland , Mörbylånga, Gamla Skogsby (Kalkstad), ̒diversity meadow’, scrubby grassland, 13 May–8 June 2015, MT, MCJ (spn ZFMK-TIS- 2549682 in NHRS) ; 1 male (only genitalia slide-mounted), Mörbylånga , Ullevi, herb-rich meadow near broadleaf forest, 14 June–15 July 2015, MT, MCJ (spn ZFMK-TIS- 2549603 in NHRS) .

Distribution and phenology. The three specimens known of this species were collected between mid-May and mid-July in both grass- and woodlands on Öland.

Figures

FIGURES 35–40. Male morphology of Winnertzia serri (35–37) and Winnertzia tumidoides (38–40). 35: Fourth flagellomere, lateral, paratype. 36: Ditto, medial. 37: Genitalia, ventral, holotype. 38: Ditto. 39: Fourth flagellomere, lateral, holotype. 40: Ditto, medial. Scales 0.05 mm. Arrows refer to characters described in the diagnoses.