Winnertzia angustistylus, 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 : 10-12

Winnertzia angustistylus sp. nov.

Figs 1–6

Diagnosis. A small to medium-sized, brown Winnertzia with vestigial mouthparts ( Fig. 5 ) and narrow wings ( Fig. 6 ). Male genitalic structures typical of this species are the slender, straight gonostylus ( Fig. 2 , ↓ 1), the unusually broad, triangular tegmen ( Fig. 1 , ↓ 2), and the short gonocoxal apodemes ( Fig. 1 , ↓ 3). Other members of the discreta group with vestigial mouthparts are W. brachypalpa and W. imbecilla , two species whose genitalic structures differ notably from that of W. angustistylus (see the diagnosis of W. imbecilla ). Females and preimaginal stages of W. angustistylus are unknown.

Other male characters. Body size 1.1–1.7 mm. Head. Eye bridge 1–2 ommatidia long dorsally. Antenna two thirds body length. Scape and pedicel same size, both concolorous with flagellum. 12 flagellomeres, flagellomeres 1–7 with translucent sensilla. Fourth flagellomere: neck 0.6–0.8 times as long as node; node slender, twice as long as broad; sensory hairs sparse; both the lateral and medial translucent sensilla long, filiform, almost linear to variously bent ( Figs 3–4 ). Palpus clearly shorter than head height, 2 setae-bearing segments; first segment compact; second segment elongate, varying in shape ( Fig. 5 ). Labella vestigial, non-setose. Thorax. Pronotal setae 1–2. Anepimeral setae absent. Lateral mediotergal microtrichia conspicuously large. Parascutellar area inconspicuous, vaguely contoured. Wing shorter than body, three times as long as broad ( Fig. 6 ). Costal cell reinforced. M 4 short, straight, CuA gently bent, both veins declining before edge of wing. Legs. Scales pointed. Basitarsal spines absent. Fore tibia 1.4 times length T 2. Acropods: claws slightly bent; basal tooth fine, barely visible; empodia one third claw length. Abdomen. Pleural membrane devoid of setae. Genitalia ( Fig. 1 ). Ninth tergite about half gonopodal length; setae largely confined to posterior half portion; posterior edge broadly rounded; anterior edge straight, sharply contoured. Gonocoxal synsclerite slightly broader than long; a large portion ventrobasally non-setose; ventral emargination U-shaped, membranous and faintly contoured basally; ventroanterior edge slightly convex; ventroposterior portions blunt-ended, ending at about same level as dorsoposterior portions; dorsal apodemes half as long as distance separating them. Gonostylus 3 times as long as broad, parallel-sided; dense, large microtrichia apically of which the longest form a sparse, inconspicuous tuft; basolateral apophysis normal size, angulated ( Fig. 2 ). Aedeagal apodeme nearly parallel-sided, often slightly constricted subapically; solid basal portion short. Aedeagal bulge with rows of small spikes. Tegmen sharply contoured except for membranous apex; lateral edges usually slightly convex; flaps small, faintly contoured; parameral apodemes moderately large.

Etymology. The name, a noun in apposition, highlights the narrow gonostyli found in this species.

Type material. Holotype. Male, Sweden, Uppland, Uppsala, Ekdalen Nature Reserve , sparse wood of oak, 27 June–17 July 2005, Malaise trap, Swedish Malaise Trap Project (trap 27, collection event 1703) (spn CEC 1797 in NHRS) . Paratypes. 4 males, same data as the holotype (spns CEC1804 – CEC 1807 in NHRS) ; 1 male, same data but collection event 486, 17 May–2 June 2004 (spn CEC 1798 in NHRS) ; 5 males, same data but collection event 1702, 13–27 June 2005 (spns CEC1799 – CEC 1803 in NHRS) .

Other material studied. Sweden: 1 male, Södermanland, Trosa, Hunga Södergård, grassland near manure pile, 24 June–5 July 2003, MT, SMTP (trap 12, collection event 69) (spn CEC 1808 in SDEI) ; 3 males, Östergötland, Ödeshög , Omberg, Stocklycke äng, meadow on limestone, 25 May–8 June 2003, MT, SMTP (trap 13, collection event 909) (spns CEC1809 – CEC 1811 in SDEI) ; 1 male, Halland, Laholm, Blåalt NR, oak-dominated forest, 12 June–8 July 2019, MT , M. Lindström (spn CEC2809 SDEI) ; 1 male, Öland , Borgholm, Skepparsäng NR, dry pine forest, 11 June–21 July 2015, MT, MCJ (spn CEC 1812 in SDEI) ; 1 male, Borgholm , Rönnerum-Abbantorp NR, scrubby fen in broadleaf forest, 17 June–15 July 2015, MT, MCJ (spn CEC 1813 in SDEI) .

Distribution and phenology. Our data suggest that W. angustistylus occurs in southern and central Sweden (Öland, Östergötland, Södermanland, Uppland) and is absent from the boreal forest zone farther north. Adults were collected between mid-May and mid-July in various different habitats.

Figures

FIGURES 1–6. Male morphology of Winnertzia angustistylus. 1: Genitalia, ventral, holotype. 2: Gonostylus, ventral, paratype. 3: Fourth flagellomere, lateral, holotype. 4: Ditto, medial. 5: Palpus, lateral, paratype. 6: Wing, dorsal, specimen from Södermanland. Scales for 1, 3 and 4, 0.05 mm; for 2 and 5, 0.025 mm; for 6, 0.50 mm. Arrows refer to characters described in the diagnosis.