Corynoptera furcifera Mohrig & Mamaev, 1987

Babytskiy, A. I. & Bezsmertna, O. O., 2021, New Records Of Sciarid Species (Diptera, Sciaridae) From Ukraine. Iii, Zoodiversity 55 (6), pp. 493-504 : 494-498

Corynoptera furcifera Mohrig & Mamaev, 1987 ( figs 1–4 )

Synonym: vitella Rudzinski & Drissner, 1992

M a t e r i a l e x a m i n e d. Ukraine, Volyn Region: outskirts of Klubochyn, Tsumanska Puscha National Nature Park , 50.96230° N, 025.83071° E, ca. 205 m a. s. l., hornbeam-oak forest, sweeping, 27.06.2017, 1 Ơ (A. Babytskiy) (No. 210, UkrBIN-795906) ; Ukraine, Volyn Region: outskirts of Sokyrychi, Tsumanska Puscha National Nature Park , 50.87516° N, 25.51393° E, ca. 210 m a. s. l., hornbeam forest with an admixture of pine and old larches, sweeping, 28.06.2017, 1 Ơ (A. Babytskiy) (No. 224A, UkrBIN-795921) ; Ukraine, Volyn Region: outskirts of Zhabka, Tsumanska Puscha National Nature Park , 50.81919° N, 25.43038° E, ca. 210 m a. s. l., old arboretum with domination of oak, hornbeam and pine, sweeping, 29.06.2017, 1 Ơ (A. Babytskiy) (No. 232, UkrBIN-795929) .

Distribution: Austria, Bulgaria, Czech Republic, Finland, Germany, Greece (mainland), Russia (Central European part; Southern Siberia), Slovakia, Sweden, Switzerland, Ukraine (new record), United Kingdom ( Heller et al., 2009; Hippa et al., 2010; Vilkamaa, 2014; Heller & Menzel, 2017; this study).

Diagnosis. Males reach 2.0– 2.3 mm in length. Head. Eye bridge consists of 3 rows of ommatidia (facets). Face fine, long with light vestiture. Maxillary palp relatively short, bright, consists of 3 palpomeres. Basal palpomere (p 1) thickened and slightly raised, with an outer bristle and a flat-edged sensory area. Sensilla long and curved. Terminal palpomere (p 3) about as long as p 1; p 2 short and ovoid, about 2 / 3 as long as p 3. Flagellum long, slightly roughened and brownish. Scape, pedicel and the base of the first flagellomere whitish-yellow, clearly lighter than the remaining flagellomeres; the 4 th flagellomere is 2.2–3.0 times as long as wide (the flagellomeres that follow are a bit longer), with coarse and protruding vestiture, setae about as long as the flagellomere width ( fig. 3 ). Neck part of flagellomeres short, brown and sharply separated. Body with sparse, long and dark brown vestiture. Thorax and abdomen yellowishbrown, gonocoxae and legs light yellow. Postpronotum bare. Mesonotum yellow, with some coarse and brownish setae, long lateral and central bristles. Scutellum with 2 conspicuously long and robust bristles. Katepisternum high and triangular. Fore tibia with spines among basal bristles. Wing wide, membrane brownish, with well-developed anal lobe; posterior wing veins indistinct and like the wing membrane without macrotrichia; stM a little longer than M-fork; M-fork broad, short-arched and wide open; c/w = 0.6–0.8; y longer than x or x = 1.0–1.4 y, both naked, stCuA very short, makes 1 / 3 – 1 / 2 x, R 1 = R or R 1 shorter, makes 2 / 3 R and falls into C in front of the base of M-fork; R 5 long, with dorsal and ventral macrotrichia. Haltere short and brownish. Legs long and slim, light-coloured. Femur of forelegs (f

1

) not noticeably thickened. Fore tibial organ (t 1) with fine and dense irregular bristle spot with no curved border ( fig. 4 ). Tibial end of t 2 and t 3 both with 2 slim and equally long spurs. Tarsal claws without teeth. Abdomen with sparse light brown vestiture. Hypopygium about as long as wide, light brown to yellowish ( fig. 1 ). Gonocoxites strong and compact, inside with short and fine setae; ventral genital base without basal lobe or basal group of bristles. Gonostylus long and ovoid (about 2.0 times as long as wide), without cavities or deep margins inside. The tip of the gonostylus narrowed, broadly rounded on the outside and without an apical tooth, upper quarter of gonostylus with 3 or 4 subapical, hyaline finger-shaped megasetae and light bristles; all megasetae about equal in length and turn inwards and downwards ( fig. 2 ). Hippa, Vilkamaa & Heller indicated the presence of a little beak-like apical tooth on the gonostylus, but it is very hard to find it among the megasetae in ventral view ( Hippa et al., 2010). Tegmen clearly wider than long, membranous, and broadly rounded apically. The field of teeth about as long as wide, with each tooth short and terminating in a single-point. Aedeagus short and fine ( Mohrig et al., 1987; Menzel & Mohrig, 2000).

Corynoptera Winnertz, 1867 is one of the most speciose genera in the family Sciaridae , containing approximately 250 species ( Pape & Thompson, 2019). However, the systematic position of species within the genus is not yet resolved. In this paper, we follow Menzel & Mohrig’s (2000) concept of Corynoptera s. l., which includes 16 species groups. Corynoptera furcifera belongs to the C. boletiphaga group with 14 species, which differ from other Corynoptera by having tibial organ t 1 without a comb-like row of bristles and a curved margin, but instead with a patch of bristles at the apex; gonostylus without an apical tooth; ventral base of hypopygium with a wide emargination, and a membranous tegmen ( Menzel & Mohrig, 2000). Also C. furcifera is similar to C. arboris Fritz, 1982 and C. saccata Tuomikoski, 1960 , but differs by having a yellow antennal scapus and pedicellus, paler than the flagellum ( Hippa et al., 2010).

M o r p h o l o g i c a l n o t e.Males reach 1.5 mm in length; the wing is 1.7–1.8 mm long and 0.6–0.7 mm wide; x and y both bare. Biometric indexes of studied specimens: width/ length of wing = 0.38–0.40; stM/M-fork = 1.05–1.19; R 1 /R = 0.69–0.84; x/y = 0.61–1.42; stCuA/x = 0.28–0.48; c/w = 0.71–0.72. Length of spur/width of tibia: leg 1 = 1.21–1.46, leg 2 = 1.48–1.99; leg 3 = 1.28–2.03. Length of metatarsus/length of tibia: leg 1 = 0.47–0.50, leg 2 = 0.42–0.44, leg 3 = 0.43–0.45. Length of tibia 3/length of thorax is 1.25–1.31.

In the previous C. furcifera descriptions there are some discrepencies in relation to wing venation measurements. On one hand, Mohrig et al., 1987 stated that y is longer than x, but Menzel & Mohrig (2000) indicated x = 1.0–1.4 y. In the studied specimens we have found both variants: the specimens No. 210 and 224A has x shorter than y and x/y = 0.61–0.71, but in the specimen No. 232 x is longer than y and x/y = 1.25–1.42. On the other hand, R 1 is specified as equal to R ( Mohrig et al., 1987) or shorter, at 2 / 3 R ( Menzel & Mohrig, 2000). In the studied specimens R 1 is shorter than R and R 1 /R = 0.69–0.84.The number of gonostylar megasetae differs in previous descriptions too: 3 ( Menzel & Mohrig, 2000) or 4 ( Mohrig et al., 1987). In the studied specimens we found 3 megasetae–the upper one is a bit thinner than the 2 lowers ( fig. 2 ).

Genus Cratyna Winnertz, 1867

Subgenus Cratyna Winnertz, 1867 s. str.

Cratyna (Cratyna) fulvicauda (Felt, 1897) ( figs 5–8 )

Synonym: gilva Rudzinski, 2000

M a t e r i a l e x a m i n e d. Ukraine, Cherkasy Region: Kaniv Nature Reserve , 49.72672° N, 31.51717° E, ca. 180 m a. s. l., maple-hornbeam forest, mass development, collected with aspirator from rotten wood, 01.07.2016, 24 Ơ, 4 ♀ (A. Babytskiy) (No. 148-9, UkrBIN-795849-50) ; Ukraine, Cherkasy Region: Yablunivka and Samoridnia , 49.43762° N, 31.18949° E, ca. 160 m a. s. l., oak-hornbeam forest, mass development, collected with aspirator from the trunk of Khmelnytskii’s Oak, 02.07.2016, 15 Ơ, 9 ♀ (A. Babytskiy) (No. 61, 150, UkrBIN-795786, 795851) ; Ukraine, Kyiv Region: outskirts of Bilohorodka , 50.42609° N, 30.23636° E, ca. 150 m a. s. l., maple-linden-oak forest, collected with aspirator from dead fruit body of Fomes fomentarius (L.) J. J. Kickx, 1867 which laid on the forest road, 16.07.2016, 1 Ơ (A. Babytskiy) (No. 99, UkrBIN-795814) ; Ukraine, Ternopil Region: outskirts of Kasperivtsi, Dniester Canyon National Nature Park, the left bank of Kasperivtsi Reservoir on Seret River , 48.67661° N, 25.85291° E, ca. 200 m a. s. l., coastal hornbeam forest on the steep slope, near the spring, sweeping, 22.06.2018, 1 Ơ (A. Babytskiy) (No. 658) ; Ukraine, Ternopil Region: outskirts of Kasperivtsi, Dniester Canyon National Nature Park, the left bank of Kasperivtsi Reservoir on Seret River , 48.68012° N, 25.85049° E, ca. 190 m a. s. l., coastal hornbeam forest on the steep slope, outcrop of siliceous rocks, sweeping, 22.06.2018, 1 Ơ (A. Babytskiy) (No. 660) ; Ukraine, Ternopil Region: outskirts of Kasperivtsi, Dniester Canyon National Nature Park, the left bank of Kasperivtsi Reservoir on Seret River , 48.67120° N, 25.85270° E, ca. 170 m a. s. l., meadowy wood glade on the edge of forest tract, collected with aspirator in the car, 23.06.2018, 1 Ơ (A. Babytskiy) (No. 664) .

D i s t r i b u t i o n: Czech Republic, Germany, Greece (mainland), Ukraine (new record), USA (New Jersey) ( Mohrig et al., 2013; Heller & Menzel, 2017; this study).

Diagnosis. Males reach 2.5–3.5 mm in length. Head. Compound eyes very sparsely haired. Eye bridge wide, consisting of 5 rows of ommatidia. Prefrons with 8 short bristles. Clypeus bare. Maxillary palps light, white-brownish, consisting of 3 palpomeres ( fig. 7 ); p 1 thickened, ca. 120 Μm in length, dorsally with extensive sensory area, 1 long and 46 short bristles; p 2 small and rounded, ca. 60 Μm in length, with 12 long and 45 short bristles; p 3 short oval, ca. 40 Μm in length. Scapus and pedicel light yellow, sharply contrasting with colour of flagellomeres. Flagellomeres dark brown with light, dense and protruding setae. Length/width of the 4 th flagellomere 1.7 ( fig. 8 ). The neck of flagellomere dark brown, relatively short — 0.3 of flagellomere width. Thorax primarily brown, with yellow sides and katepisternum. Mesonotum with strong dark brown bristles. Dorsocentral and acrostichal bristles strong; 6–8 long lateral bristles. Scutellum with 6–8 long apical and several short distal bristles. Postpronotum bare. Wing 2.0 mm in length, with brownish membrane; anal lobe well developed; c/w = 0.80; R and R 1 with macrotrichia (14–16 in total), R 1 /R = 1.10, R 1 falls into C before the base of M-fork; x and y about equal in length, x with 2–3 macrotrichia, y bare; stCuA short, makes half of x. Haltere brown. Coxae and legs light, yellow-brownish; bristles on coxae dark brown. Tibial organ t 1 with 1 spur and dense, multi-row bristle patch, proximally pyramid shaped, which is different from the tibial vestiture with stronger and darker bristles on the edge of the patch ( fig. 6 ); t 2 and t 3 both with 2 spurs; t 3 with well-developed dorsal row of spines. Abdomen brown with dense dark brown bristles. IX tergite narrow pyramidal shaped. Hypopygium very bright, brownish-yellow, clearly brighter than abdomen ( fig. 5 ). Gonocoxae almost twice as wide as long, with thick bristles on the ventral base. Tegmen relatively small, trapezoidal. Aedeagus very short. Gonostylus bloated, apically slightly tapered with long bristles. There are 4 bright pairs of megasetae on the inner side of the gonostylus ( Rudzinski, 2000; Mohrig et al., 2013).

Cratyna Winnertz, 1867 s. l. separates from other Sciaridae by having short palps with a strong tendency to reduction of the palpomeres, especially p 2, which is sometimes wartlike in form. According to Menzel & Mohrig (2000), Cratyna is divided into 4 subgenera — Cratyna Winnertz, 1867 s. str., Spathobdella Frey, 1948 , Peyerimhoffia Kieffer, 1903 and Diversicratyna Menzel & Mohrig, 1998 , but some authors consider Peyerimhoffia to be a separate genus ( Vilkamaa & Hippa, 2005; Babytskiy et al., 2018). Cratyna fulvicauda belongs to the subgenus Cratyna s. str., which includes about 30 species in the Palaearctic and differs from other subgenera by the absence of an apical tooth on the gonostylus. Cratyna fulvicauda is similar to Cr. ambigua (Lengersdorf, 1934) , Cr. subalpina ( Mohrig & Mamaev, 1990) and Cr. alpina (Mohrig & Menzel, 1992) , but can be easily separated by the structure of the gonostylus, yellow sides of the thorax and bright gonocoxae ( Rudzinski, 2000; Mohrig et al., 2013).

According to Mohrig et al. (2013), Cr. fulvicauda was not collected in Central Europe before 1989 and they suggested that the species may have been introduced from North America, where it has been known for at least a century. In Ukraine we have found Cr. fulvicauda inhabiting natural biotopes such as the broadleaf forests of the Kaniv Nature Reserve and Dniester Canyon National Nature Park (see material examined). In early July 2016, we recorded the mass development and swarming of Cr. fulvicauda imagoes in Cherkasy Region. In the 1 st of July we observed the mass flight of imagoes above a rotten hornbeam trunk in the maple-hornbeam forest in Kaniv Nature Reserve and in the 2 nd of July we recorded the same phenomenon in the oak-hornbeam forest above an ancient (ca. 800 years old) very rotten oak tree, the so-called “Khmelnytskii’s Oak” (now completely lost). In both cases male and female imagoes copulated immediately after eclosion, when they were still in a teneral state and completely white in color.

M o r p h o l o g i c a l n o t e. Males reach 4.0 mm in length, with a wing measuring 2.5– 2.7 mm long and 1.0– 1.1 mm wide; x bare, y with 5–7 macrotrichia. Biometric indexes of studied specimens: width/length of wing = 0.39–0.44; stM/M-fork = 0.83–1.05; R 1 / R = 1.20– 1.44; x/y = 0.74–1.10; stCuA/x = 0.36–0.63; c/w = 0.76–0.83. Length of spur/width of tibia: leg 1 = 1.05–1.36, leg 2 = 1.61–2.17; leg 3 = 1.63–2.00. Length of metatarsus/length of tibia: leg 1 = 0.54–0.58, leg 2 = 0.47–0.49, leg 3 = 0.43–0.49. Length of tibia 3/length of thorax is 1.21–1.36.

Figures

Figs 1–4.Corynoptera furcifera, male: 1 — hypopygium, ventral view; 2 — gonostylus, ventral view; 3 — fourth flagellomere, lateral view; 4 — anterior apex of fore tibia (t1) with tibial organ, lateral view. Scale bars: 0.10 mm.

Figs 5–8.Cratyna fulvicauda, male: 5 — hypopygium, ventral view; 6 — anterior apex of fore tibia (t1) with tibial organ, lateral view; 7 — maxillary palp, lateral view; 8 — fourth flagellomere, lateral view. Scale bars: 0.10 mm.