Urytalpa trivittata ( Lundström, 1914 )

Kjaerandsen, Jostein, Martinsson, Svante, Hedmark, Kjell & Evenhuis, Neal L., 2009, On the genus Urytalpa Edwards (Diptera: Keroplatidae) in the Nordic and Nearctic regions, with fixation of a new type species and a key to world males, Zootaxa 2160 (1), pp. 29-50 : 43-48

Urytalpa trivittata ( Lundström, 1914)

( Figs 2B , 4B , 10A–D , 11C–D )

Platyura trivittata Lundström, 1914:10

Urytalpa trivittata ; Bechev & Koç 2008:31, figs 9–10

Diagnosis. Most similar to U. dorsalis but differs by having more slender and less petiolated and less laterally compressed abdomen ( Fig. 2B ) and by having the thoracic stripes distinctly separated. The larger apicomedial outgrowth of the gonocoxite with 5–6 strong setae in a row ( Fig. 10A ) is a distinctive character for this species. Urytalpa dorsalis and U. trivittata differ from the other Nordic species in having gonocoxites without larger outgrowths and the gonostylus is retracted dorsally into the gonocoxites. In U. trivittata , however, the gonostylus is subtriangular in lateral view and somewhat larger ( Fig. 10C ). The female can be separated from U. dorsalis and U. macrocera by the combination of an oblong and petiolated cercus, sternite VIII having truncated apicomedial corners with a narrow setose excavation, and by having distinctly ovate spermathecae with a relatively thin inner wall ( Figs 11C–D ).

Description. Male (n=5). Body length 6.5–8.5, 7.1 (n=10) mm. Wing length 5.14–5.88, 5.5 mm, or 3.24–3.64, 3.39 as long as profemur. Antenna length 2.2–2.64 (n=4) mm. Coloration (specimen in alcohol, Fig. 2B ). Head brown with mouth parts paler. Antenna brown, scape, pedicel and basal part of first flagellomere paler. Thorax yellow with pale antepronotum; dark brown mesonotal stripes distinctly separated, narrowly surrounded by pale yellow ground; humeral area pale, extending laterally to behind wing base. Wings clear, yellow tinged, veins brown. Halter pale. Legs slightly paler than thorax. Abdomen brown; tergites I–V with narrow pale bands apically; tergites VI–IX dark brown; sternites I–V pale; terminalia yellowish brown. Terminalia ( Fig. 10 ). Gonocoxite connected ventrally by a narrow strip only; apically with a distinct apicomedial outgrowth with 5–6 strong setae in a row. Large hypandrial lobe forming thin hyaline plate ventromedially. Gonostylus retracted into gonocoxite, small and subtriangular in lateral view with the tip pointing dorsally. Aedeagal apparatus long but not high, with less compressed plate extending anteriorly into segment V, and long associated apodemes laterally. Tergite IX without outgrowths, apical corner pointed ventrally, without patch of short internal setae; with shallow posterior and deep anterior U-shaped incision. Proctiger small and short, cercus broadly ovate in lateral view.

Female (n=1). Body length 7.5 mm. Wing length 6 mm. Antenna length 1.82–1.86 mm. Coloration. As in male with dark brown mesonotal stripes distinctly separated. Terminalia ( Figs 11C–D ). Cercus oblong and petiolated. Sternite VIII with truncated corners, with a narrow excavation apicomedially covered with short stiff setae. Spermathecae distinctly ovate, spermathecae and ducts with medium thick inner walls.

Remarks. Association of the single female is based on co-occurrence and coloration matching with a male, but deviating slightly from the generic diagnosis in having the A 1 vein fading slightly before the wing edge.

Distribution. European; with scattered records only from Finland, Germany, Italy, Norway and Sweden. Possibly boreal-mountainous with main distribution in northern parts of the boreal zone.

Material examined: ITALY: Pellaud , Vallée de Rhêmes (Aosta), 1800–2000 m a.s.l., 8 Oct 1978 ( MNHN, Leg. L. Matile) — 1 male ; NORWAY: FV, Alta , Detsika, Buolamalia, 69°51'38"N, 023°19'38"E, in sandy slope, 24 Jun–16 Jul 1996 ( ZMUN, Leg. L. O. Hansen & H. Rinden) — 1 male ; 6 Aug–25 Sep 1996 ( MZLU, Leg. L. O. Hansen & H. Rinden) — 1 female, 3 males ; SWEDEN: LU, Jokkmokk , Kaltisbäcken 1 km NNE Messaure, 66°41'26"N, 020°22'37"E, 250 m a.s.l., 1–10 Jul 1968 ( MZLU, Leg. K. Müller) — 1 male ; Kaltisbäcken , loc. 7, Sapta, 10–20 Aug 1968 ( MZLU, Leg. K. Müller) — 1 male ; 21–30 Aug 1968 ( MZLU, Leg. K. Müller) — 11 males ; Kaltisbäcken , loc. 20 ( MZLU, Leg. K. Müller) — 1 male ; Jokkmokk , Messaure, 66°40'57"N, 020°21'48"E, 175 m a.s.l., 6–10 Sep 1968 ( MZLU, Leg. K. Müller) — 2 males ; Jokkmokk , Kanibäcken, 8 km SE Messaure, 66°36'45"N, 020°27'20"E, 100 m a.s.l., 1–10 Aug 1968 ( MZLU, Leg. K. Müller) — 2 males ; 6–10 Sep 1968 ( MZLU, Leg. K. Müller) — 3 males ; Kvikkjokk , along the path to point 749 Prinskullen, 66°57'24"N, 017°41'27"E, 600 m a.s.l., spruce forest dominated by Aconitum lycoctonum , 6 Aug 1997 (Coll. & Leg. K. Hedmark) — 1 male ; TO, Kiruna , Abisko, 68°21'01"N, 018°49'50"E, LF 5 - 150– 500 m W Naturv. stn., 8–15 Sep 1975 ( MZLU, Leg. K. Müller) — 1 male .

Figures

FIGURE 2. Habitus photos of males of Nordic species of the genus Urytalpa Edwards. — A. Urytalpa dorsalis (Staeger, 1840). — B. Urytalpa trivittata (Lundström, 1914). — C. Urytalpa atriceps (Edwards, 1913). — D. Urytalpa macrocera (Edwards, 1913). — E. Urytalpa galdes Hedmark & Kjaerandsen sp. n.

FIGURE 4. Wing photos of males of Nordic species of the genus Urytalpa Edwards. — A. Urytalpa dorsalis (Staeger, 1840). — B. Urytalpa trivittata (Lundström, 1914). — C. Urytalpa atriceps (Edwards, 1913). — D. Urytalpa macrocera (Edwards, 1913). — E. Urytalpa galdes Hedmark & Kjaerandsen sp. n.

FIGURE 10. Male terminalia of Urytalpa trivittata (Lundström, 1914). — A. Sternite IX, hypandrial lobe and internal aedeagal apparatus, ventral view (pre-terminal segments not illustrated). — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view. — D. Gonostylus in lateral view, enlarged.

FIGURE 11. Female terminalia and spermatheciae of Urytalpa species (pre-terminal segments not illustrated). — A. U. dorsalis (Staeger, 1840) in lateral view. — B. U. dorsalis, ventral view of sternite VIII. — C. Urytalpa trivittata (Lundström, 1914) in lateral view. — D. U. trivittata, ventral view of sternite VIII. — E. Urytalpa macrocera (Edwards, 1913) in lateral view. — F. U. macrocera, dorsal view of sternite VIII.