Arctepidosis jamalensis Mamaev, 1990

Jaschhof, Mathias & Jaschhof, Catrin, 2017, Mycophagous gall midges (Diptera, Cecidomyiidae: Lestremiinae, Micromyinae, Winnertziinae, Porricondylinae): first records in Sweden and descriptions of closely related new species from elsewhere, Zootaxa 4226 (4), pp. 546-570 : 558-560

Arctepidosis jamalensis Mamaev, 1990

Fig. 7A ̄B

Arctepidosis jamalensis , type species of the genus Arctepidosis , was described on the basis of two males collected in western Siberia, Russia, in 1981 ( Mamaev 1990). The original description contains no illustrations other than a wing sketch ( Mamaev 1990: fig. 1.4), rendering it useless for the purpose of identification. MJ studied the holotype of A. jamalensis in October 2012, and from the notes and drawings made at that time it is obvious that three specimens we recently found in Sweden belong to this species—the first finds for 35 years. Another species described of Arctepidosis , A. paneliusi Mamaev & Zaitzev, 1998 from Finland, might be identical with A. jamalensis . In the holotype male, the only specimen existing of A. paneliusi , the genitalia are squashed by the cover slip, making it difficult to assess possible distinctions to A. jamalensis . The gonostyli of A. paneliusi appear to be more compact and the tegmen slightly different in structure. The genitalic illustration of A. paneliusi in Mamaev & Zaitzev (1998: fig. 1) shows the gonostylus correctly, but the tegmen lacks detail and the gonocoxites are considerably too long. It follows a description of the male of A. jamalensis , which supplements and partly corrects the description by Mamaev (1990).

Male description. Body length 1.4̄ 1.5 mm. Head. Setae sparse, confined to posterior half of head capsule. Eye bridge shifted somewhat ventrally, interrupted dorsally by wide gap without ommatidia. Scape and pedicel lighter than flagellum; 14 flagellomeres; circumfila on flagellomeres 1̄8, with short posterior extensions ( Fig. 7B ). Neck and node of fourth flagellomere equally long. Palpus almost as long as head height, 4 subcylindrical segments. Thorax. Anepisternum asetose. Anepimeron setose. Wing. Conspicuously narrow, length / width 3.5. Costal break distinct, situated slightly beyond apex of wing; Rs perpendicular to R1 and R5; M1+2 absent; a remnant M4 present at wing margin; CuA extending to wing margin. Legs. Basitarsi with small microtrichose lobe but no spine apically. Claws with 1 large tooth basally. Empodia as long as claws. Genitalia ( Fig. 7A ). Ninth tergite large, extending unusually far anteriorly, appears to be merged with gonocoxites laterally, with transparent, asetose portion posteriorly, posterior edge straight, deeply incised medially. Gonocoxites: ventral emargination U-shaped, reinforced basally; dorsal bridge broadly rounded, with anterior convexities slightly indicated. Gonostylus directed somewhat dorsally, twice as long as wide, slightly curved and pointed, dense microtrichia apically. Tegmen three times longer than wide, parallel-sided; a rectangular process ventroapically that appears to hold the ejaculatory apodeme in position; posterior edge rounded, finely serrated. Ejaculatory apodeme slightly longer than gonocoxites, slender, moderately sclerotized, membranous and slightly furcate apically. Hypoproct and cerci of normal outline (not drawn).

Previous distribution. Russia ( western Siberia ) . Occurrence in Sweden: Öland.

Specimens studied. SWEDEN: male (CEC155), Öland, Mörbylånga, Gamla Skogsby, mixed deciduous forest with much dead ash, 9 June ̄ 14 July 2015, Malaise trap, M. & C. Jaschhof; male (CEC274), Mörbylånga, Stora Dalby forest NR, mixed deciduous forest with much dead ash , 8 June–8 July 2015, Malaise trap, M. & C. Jaschhof; male (CEC275), Öland, Borgholm, Rönnerum-Abbantorp NR, small scrubby fen surrounded by deciduous forest, 17 June–15 July 2015, Malaise trap, M. & C. Jaschhof.

Figures

FIGURE 7 A – B. Arctepidosis jamalensis, male (specimen from Sweden). A: Genitalia, ventral. B: First flagellomere, lateral. Scales for A – B, 0.05 mm.