Linnaemya bergstroemi, Pohjoismäki, Jaakko & Haarto, Antti, 2015

Pohjoismäki, Jaakko & Haarto, Antti, 2015, Linnaemya bergstroemi n. sp. (Diptera: Tachinidae) — a new parasitoid fly from the Finnish Lapland, Zootaxa 4059 (3), pp. 581-597 : 584-587

Linnaemya bergstroemi n. sp.

( Figs 1 , 6 , 11–12 , 21–22 , 31, 33, 35 , 41, 43 , 50–54 )

Type material. Label data of the type series is reported verbatim as written on the labels, a single slash (/) separating lines on a same label and a double slash (//) separating different labels. Any comments or explanations are given in square brackets. Coordinates on the labels are given in the old national Finnish coordinate system (YKJ; see Ollikainen & Ollikainen 2004). Holotype (♂) [ ZMUO]: Finland, InL: INARI / 759:51 [Kaunispää Fjell, 68°25'21.7"N, 27°25'29.3"E] larva / 28.08.1997 / J. ITÄMIES & / E. ERKINARO leg. // HOST: LEP. / Arctiidae / Pararctia lapponica // http://id.zmuo.oulu.fi / ZMUO.023894 [qr-coded registration number]. Paratypes: 2 ♀♀ [ ZMUO]: same data as holotype [qr-codes ZMUO.023895–6]; 3 ♀♀ [ ZMUO]: Finland, InL: INARI / 759:51 [Kaunispää Fjell, 68°25'21.7"N, 27°25'29.3"E] larva / 23.8.2001 / J. ITÄMIES leg. // HOST: LEP. / Arctiidae / Pararctia lapponica ; 1 ♂ [ ZMH], 4 ♀♀ [3 in ZMUO, two with qr-codes ZMUO.023897–8; 1 in ZMH]: Finland, InL: UTS- / JOKI 775:50 [Áilegas Fjell, 69°48'42.5"N, 26°16'27.8"E] / larva 18.08.2001 / J. ITÄMIES leg. // HOST: LEP. / Arctiidae / Pararctia lapponica [ DNA sample taken from one female from the latter series, see Tab. 1 ].

Etymology. The new species is dedicated to Mr. Christer Bergström (Uppsala, Sweden) as an acknowledgment of his life-long work on Nordic Tachinidae .

Diagnosis. Linnaemya bergstroemi n. sp. is an unusual Linnaemya with a striking shiny black appearance, 3–4 katepisternal setae, 3 dorsal preapical setae on the tibiae and irregular discal setae on the abdomen.

Description. Male ( Figs 1 , 11–12 , 31, 33, 35 , 41, 43 ) (characters in square brackets refer to the holotype).

Body length: 7.2–[10.1] mm (n = 2). Head ( Figs 11–12 ). Black in ground color with thin gray or grayish-white microtomentum on face, parafacial and fronto-orbital plate along eye margin. Antenna matt black with thin grayish microtomentum, scape erect, pedicel elongated, [2.1]–2.5 times as long as wide, first flagellomere rectangular and scarcely longer than pedicel; arista black, thickened along basal 2/3 and evenly tapering; second aristal segment 4.0 times as long as wide. Eyes densely covered with dark ommatrichia, 5–6 times longer than the width of an eye facet. Frontal vitta and genal groove reddish-brown. Frons, at narrowest point, 0.4–[0.7] times as wide as an eye in dorsal view; frontal setae strong, medioclinate and reaching level of middle of pedicel. Gena, in profile at narrowest point, 0.35–[0.41] times as high as vertical eye diameter. Vibrissa 0.7 times as long as height of face (as measured from antennal insertion to edge of mouth), inserted at level of lower facial margin. Facial ridge above vibrissa with 3–4 strong setae as well as 2–3 additional weaker setae. Height of face about equal to length of frons. One weak proclinate orbital seta; ocellar setae strong, proclinate, inserted halfway between anterior ocellus and posterior ocelli. Outer vertical seta strong. In lateral view, parafacial about as wide as base of first flagellomere. Occiput with three irregular rows of black setae behind the postocular row of setae. Occiput and postgena with pale orange hair-like setulae. Palpus dark brown, cylindrical, about half the length of pedicel and with two fine setulae at tip. Prementum narrow and elongated, as long as or longer than face. Thorax. Dorsally shiny black with very weak microtomentum; scutum with somewhat indistinct longitudinal black stripes. Scutum with 2+1 acrostichal, 3+3 dorsocentral and 1+3 intra-alar setae. Scutellum black with reddish transparency at tip, four pairs of scutellar setae, apical pair strong and forming an angle of about 60˚ with plane of scutellum. Pleura with thin gray microtomentum. Background setulae on thorax sparse, erect and about 0.2–0.4 times the length of setae. Proepisternum bare and katepisternum with 3–[4] setae. Legs black; apices of femora with a diffuse and narrow brownish strip. Fore tibia with a regular row of [7]–9 long ad setae as well as an irregular row of 2–[4] pd (posterodorsal) setae. Mid and hind tibiae with 3–[4] strong ad as well as pd setae; three dorsal preapical setae on all tibiae. Wing with a brownish tinge, slightly more hyaline along hind margin. Tegula black, basicosta brownishyellow, the same color as upper and lower calypters. Costal spine not differentiated from surrounding setae. R4+5 with 4–[5] setulae dorsally and 3–[4] setulae ventrally. Bend of vein M, besides a fold, also with an appendage extending halfway to wing margin. Halteres black-brown with a lighter knob. Abdomen. Shiny black, dorsally and ventrally with thin gray microtomentum visible only when viewed posteriorly. Sides of abdomen with red markings restricted to tergite 3, but completely black in the paratype. Syntergite 1+2 with middorsal depression extending halfway to hind margin and with 4–5 irregular lateral setae but no median marginal setae. Three pairs of unarranged median discal setae with almost a full row of marginal setae on tergites 3 and 4. Tergite 5 densely covered with long, irregular setae. Terminalia ( Figs 31, 33, 35 ). Posterior margin of sternite 5 with a distinct rounded projection on the inner margin of each lobe and with a narrow, U-shaped median cleft ( Fig. 33 ). Tergite 6 wide and short, well sclerotized, with strong setae. Epandrium flat, almost as high as the more prominent surstyli ( Figs 31, 35 ). Syncercus in dorsal view basally rather wide and evenly tapering towards a blunt apex ( Fig. 35 ); in lateral view, moderately curved from base to apex dorsally, smooth and of even thickness ( Fig. 35 ). Surstylus broad, blunt and somewhat curved. Distiphallus apically and lateroventrally sclerotized ( Fig. 41 ), with a sclerotized ridge; membranous parts of the dorsal vesica of distiphallus densely covered with minute spicules. Pregonite wide, hook-like, about twice as long as wide. Basiphallus sclerotized, apart from the membranous epiphallus.

Female ( Figs 6 , 21–22 ). Differs from male as follows:

Body length: 8.2–9.4 mm (n = 9). Head ( Figs 21–22 ). Eyes with very sparse ommatrichia, about as long as 1.0–1.5 times the width of an eye facet. Frons broader, at its narrowest point 0.7–0.9 times as wide as an eye in dorsal view. Two or 3 strong proclinate orbital setae. Gena in lateral view 0.5–0.6 times as high as vertical eye diameter. Thorax. 2+2 acrostichal setae. Fore tarsomeres flattened and long; fore tarsi as long as or longer than fore tibiae. Abdomen without red markings and with fewer setae: two pairs of irregular, median discal setae on tergites 3 and 4. These setae either arranged in a straight line or one or two of them scattered away from the line. In three paratype females, middorsal depression on syntergite 1+2 reaching the margin. Marginal setae on tergite 4 not forming a complete row but interrupted latero-medially. Tergite 5 elongated, longer than tergite 4 and with 2–3 irregular rows of discal setae.

Puparium ( Figs 50–54 ). Length 5.2–7.4 mm, maximum width 2.7–3.0 mm (n = 8). Reddish-brown to dark brown, cylindrical and evenly rounded ( Figs 50–51 ). Outer integument smooth, segments well-defined, each thoracic and abdominal segment ventrally with 2–3 irregular rows of minute spines ( Fig. 52 ). Thoracic segments and anterior abdominal segments with two rows of spines, anterior spines finer. Anterior spiracles oval, situated at midline (anterior view) and opening somewhat laterally ( Fig. 53 ). Posterior spiracles well separated, flat and rounded, positioned slightly dorsad to midline (posterior view), black, smooth and with transverse grooves ( Fig. 54 ). No spiracular slits visible. Anal plate oval and well defined.

Figures

FIGURES 1 – 5. Linnaemya spp., male habitus in lateral view. Scale bars: 1 mm. 1. Linnaemya bergstroemi n. sp., holotype (Finland, Inari). 2. Linnaemya anthracina Thompson (Canada, Northwest Territories) (photo by J. E. O’Hara (CNC), used with permission). 3. Linnaemya varia Curran (Canada, Yukon). 4. Linnaemya nigrescens Curran (Canada, Yukon). 5. Linnaemya tessellata (Brooks) (Canada, Yukon).

FIGURES 6 – 10. Linnaemya spp., female habitus in lateral view. Scale bars: 1 mm. 6. Linnaemya bergstroemi n. sp., paratype (Finland, Inari). 7. Linnaemya anthracina Thompson (Canada, Alberta). 8. Linnaemya varia Curran (Canada, Yukon). 9. Linnaemya nigrescens Curran (Canada, Yukon). 10. Linnaemya tessellata (Brooks) (Canada, Quebec).

FIGURES 11 – 20. Heads of Linnaemya spp., males. Scale bars: 1 mm. 11 – 12. Linnaemya bergstroemi n. sp., holotype (Finland, Inari). 11. Lateral view. 12. Dorsal view. 13 – 14. Linnaemya anthracina Thompson (Canada, Alberta). 13. Lateral view. 14. Dorsal view. 15 – 16. Linnaemya varia Curran (Canada, Yukon). 15. Lateral view. 16. Dorsal view. 17 – 18. Linnaemya nigrescens Curran (Canada, Yukon). 17. Lateral view. 18. Dorsal view. 19 – 20. Linnaemya tessellata (Brooks) (Canada, Yukon). 19. Lateral view. 20. Dorsal view.

FIGURES 21 – 30. Heads of Linnaemya spp., females. Scale bars: 1 mm. 21 – 22. Linnaemya bergstroemi n. sp., paratype (Finland, Inari). 21. Lateral view. 22. Dorsal view. 23 – 24. Linnaemya anthracina Thompson (Canada, Alberta). 23. Lateral view. 24. Dorsal view. 25 – 26. Linnaemya varia Curran (Canada, Yukon). 25. Lateral view. 26. Dorsal view. 27 – 28. Linnaemya nigrescens Curran (Canada, Yukon). 27. Lateral view. 28. Dorsal view. 29 – 30. Linnaemya tessellata (Brooks) (Canada, Quebec). 29. Lateral view. 30. Dorsal view.

FIGURES 31 – 39. Linnaemya spp., males. Scale bars: 0.5 mm. 31. Linnaemya bergstroemi n. sp., holotype (Finland, Inari), undissected terminalia in left lateral view. The arrow shows the characteristically rounded projection on the posterior margin of sternite 5, a feature shared with Linnaemya anthracina Thompson. 32. Linnaemya varia Curran (Canada, Yukon), undissected terminalia in left lateral view. Notice the differences in the size and shape of the epandrium and convex posterior margin of sternite 5 as compared with L. bergstroemi n. sp. Both these features are in common with all other members of the subgenus Ophina Robineau-Desvoidy. 33 – 34. Sternite 5 in ventral view. 33. Linnaemya bergstroemi n. sp., paratype (Finland, Inari). The arrow points to the rounded projection on the posterior margin. 34. Linnaemya anthracina Thompson (Canada, Alberta). Notice the differences in the size and shape of the rounded projection on the posterior margin as well as in the shape of the median cleft of the sternite as compared with L. bergstroemi n. sp. 35 – 39. Syncercus and surstyli in dorsal (A) and lateral (B) views. 35. Linnaemya bergstroemi n. sp., paratype (Finland, Inari). 36. Linnaemya anthracina (Canada, Alberta). 37. Linnaemya varia Curran (Canada, Northwest Territories). 38. Linnaemya nigrescens Curran (Canada, Nova Scotia). 39. Linnaemya tessellata (Brooks) (Canada, Yukon).

FIGURES 40 – 49. Linnaemya spp., structures of the male terminalia in lateral view. Scale bars: 0.5 mm. Abbreviations: aed apod = aedeagal apodeme; bph = basiphallus; da-ds = dorsoapical surface of distiphallus; ds = distiphallus; ej apod = ejaculatory apodeme; epiph = epiphallus; pog = postgonite; prg = pregonite; sc = sclerotized ridge. 40. Generalized view of the Linnaemya anthracina Thompson (Canada, Alberta) phallus with gonites attached. The epiphallus is partially covered by the postgonite. 41. Linnaemya bergstroemi n. sp., paratype (Finland, Inari). Gonites separated from the phallus. 42. Linnaemya anthracina (Canada, Alberta). Gonites separated from the phallus. Notice the difference in the relative dimensions of the pregonite as compared with L. bergstroemi n. sp. 43. Basiphalli of L. bergstroemi n. sp. and L. anthracina. 44. Linnaemya varia Curran (Canada, Yukon). 45. Linnaemya nigrescens Curran (Canada, Nova Scotia). 46. Linnaemya tessellata (Brooks) (Canada, Yukon). 47. Linnaemya picta (Meigen) (type species of the subgenus Ophina Robineau-Desvoidy) (Germany, Hessen). 48. Linnaemya rossica Zimin (Finland, North Karelia). 49. Linnaemya tessellans (Robineau-Desvoidy) (subgenus Bonellimyia Townsend) (Germany, Hessen). Notice the sclerotized ridge on the distiphallus.

FIGURES 50 – 54. Puparium of Linnaemya bergstroemi n. sp. (Finland, Inari). 50 – 51. Scale bar: 1 mm. 50. Oblique posterior view. 51. Lateral view with ventral side down. 52. Detail of ventral surface showing the rows of minute spicules on the abdominal segments. Scale bar: 200 mm. 53 – 54. Scale bar: 1 mm. 53. Anterior view. 54. Posterior view showing the position of the posterior spiracles.