Pipunculus omissinervis Becker, 1889

Kehlmaier, Christian, 2008, Finnish Pipunculidae (Diptera) studies Part I: Taxonomic notes on Cephalops Fallén, 1810, Pipunculus Latreille, 1802 and Tomosvaryella Aczél, 1939, Zootaxa 1672, pp. 1-42 : 20-23

Pipunculus omissinervis Becker, 1889

( Figs 38–39, 42 & 68–69 )

Pipunculus nartshukae Kuznetzov, 1990: 378 . syn. nov. Pipunculus omissinervis Becker, 1889: 83 .

Pipunculus phaeton Coe, 1966: 49 . syn. nov.

Material: Switzerland, Eggischhorn, Furka Pass, no. 19326: 1ɗ (holotype), 23.VII., Becker ( MNHU); Finland, N, Sibbo, Nevas, 6687:412: 2ɗ, 7.–13.VII.1985; 1ɗ, 13.–20.VII.1986; 1ɗ, 22.–28.VI.1986; 1ɗ, 1.– 6.VII.1986; 4ɗ, 15.–21.VI.1986; 2ɗ, 28.VII.–4.VIII.1986; 1ɗ, 22.–26.VIII.1984, Albrecht; Finland, Helsinki, Kallahdenniemi: 1ɗ, 18.VI.2003, Kahanpää ( PCJK); Germany, Bavaria, Oberallgäu, Ofterschwang, 1000m, 10°13’39’’E 47°29’52’’N: 1ɗ, 12.VIII.2004, Kehlmaier ( PCCK); Germany, Bavaria, Oberallgäu, Sonthofen, 1000m, 10°19’13’’E 47°31’10’’N: 1ɗ, 11.VIII.2004, Kehlmaier ( PCCK); Hungary, Nagy kovácsi, Júlia major: 1ɗ, 25.–27.IV.1983, Visnyovszky ( HNHM); Hungary, Hárskut, Esztergáli-v.: 1ɗ, 27.IV.1977, Tóth ( HNHM); Hungary, BNP Hármaskút: 1ɗ, 31.V.–4.VI.1982, Bessenyi ( HNHM).

Male: Body length: 3.8–4.7mm. Wing length: 4.1–5.1mm. Flagellum dark brown. Frons brown pollinose. Eyes meeting for length of frons or slightly more (13–16 facets). Occiput grey pollinose except posterior to ocellar triangle with brown pollinosity, which occasionally can be extended to as much as entire upper half. Postpronotal lobe dark brown. Prescutum and scutum entirely brown pollinose but can be greyish in anterior quarter. Pleura with anepimeron, katepimeron, posterior margin of anepisternum and upper margin of katepisternum light brown pollinose but this can be reduced to entirely absent, otherwise weakly grey pollinose.

Scutellum with apical fringe of about 12 evenly spaced hairs. Subscutellum grey pollinose but occasionally some weak brown pollinosity can be present centrally or in upper lateral corners. LTC about 1.0–1.7 times LFC. Trochanter yellowish to brown. Femur with base (rarely) and apex narrowly yellow. Hind femur weakly concave in ventrobasal half. Tibia yellowish, ventrally darkened in apical two thirds. Tarsi yellowish to brown, with distitarsi darkest. Pulvilli of front leg slightly shorter than distitarsi. Tergite 1 anterodorsally brown, otherwise grey pollinose. Dorsally brown pollinosity covering entire tergite 2, anterior three quarters of tergite 3, anterior half to two thirds of tergite 4 and anterior quarter of tergite 5, otherwise shining. Laterally, tergites 2–5 entirely brown pollinose or with distinct triangular patches of greyish-brown to grey pollinosity in posterior half. Membranous area key-hole shaped. Surstyli elongated but can be slightly shorter than figured here ( Figs 38–39 ). Depending on the perspective, the shape of the surstyli can vary. Only two of the three ejaculatory ducts are distinctly sclerotized in distal half.

Female: Conspecific with P. c a m p e s t r i s (see above for characterisation).

Annotations: Becker (1889) collected a single male at Mount Eggischhorn. The specimen’s label states “Furka”, a pass about 30km away according to De Meyer (1996). The female sex cannot be differentiated from P. campestris at present. The male from Hármaskút in Hungary has a short additional vein M 2 in its left wing.

A comparison of European P. omissinervis and Nearctic Pipunculus hertzogi ( Rapp, 1943) showed that male terminalia are conspecific. However, comparison of yet unpublished molecular data for a 658bp fragment of coxI suggests that both taxa have to be considered as distinct lineages (tested for one Nearctic male P. hertzogi (Skevington unpublished) and five Palaearctic male P. omissinervis specimens (Kehlmaier unpublished)). This is especially interesting because P. hertzogi has lately been thoroughly reanalyzed by Skevington & Marshall (1998) who also established it as a senior synonym of Pipunculus phaeton Coe, 1966 , originally described from 5ɗ and 6Ψ collected in the southern part of Great Britain. Because of the present results it is proposed to regard P. hertzogi as an exclusively Nearctic taxon and transfer P. phaeton to synonymy with P. omissinervis instead (syn. nov.). The citings of P. hertzogi from mainland Italy and eastern Russia (both Skevington & Marshall 1998) should be attributed to P. omissinervis .

The male holotype and additional two male and three female paratypes of P. phaeton were obtained for study but are not included in the listing above as they were not used for characterising the taxon due to the reasons stated below: Great Britain, Oxford: 1ɗ (holotype), 27.VI.1909, Malloch (NHM); Great Britain, Dorset, Hamworthy: 1ɗ (paratype), 12.VIII.1894, Yerbury (NHM); Great Britain, Glamorgan, Port Talbot, Margam.: 1ɗ (paratype), 24.VIII.1908, Yerbury (NHM); Great Britain, Cheshire, Rostherne: 1Ψ (paratype), Britton (NHM); Great Britain, Hants., Woolmer Forest: 1Ψ (paratype), 12.VII.1903, Yerbury (NHM); Great Britain, Somerset, Sharpham: 1Ψ (paratype), 22.VIII.1922, Audcent (NHM). Male and presumably female terminalia are conspecific with P. omissinervis— the male holotype was dissected—but certain outer morphological features concerning pollinosity stand in contrast: e.g. male with abdominal tergites 2–5 almost entirely shining, some weak brown pollinosity may be present laterally or dorsally along anterior margin, or female with frons shining in upper half at least and prescutum and scutum narrowly grey pollinose along anterior margin (up to anterior quarter), laterally almost or right down to wing base and otherwise shining. Despite this, it is proposed not to question the taxonomic status of P. phaeton at present until fresh material for molecular work can be acquired and additional evidence generated. Also, the specimens recorded in the past (see Falk & Chandler 2005, De Meyer 1989b and De Meyer & Beuk 2002) should be critically reviewed.

Pipunculus nartshukae Kuznetzov, 1990 was described from a single male collected in Mongolia and deposited at ZISP (not studied). The surstyli figured in Kuznetzov (1990) (his Figs 3–5 & 20 ) seem to be identical to P. omissinervis , as already pointed out by Skevington & Marshall (1998). Kuznetzov (1990) separates P. nartshukae from P. omissinervis through more strongly bent surstyli in lateral view and by less narrowing (presumably front) coxae in their apical half—in P. omissinervis the apex of the front coxa has approximately half its maximum width, what seems to be characteristic for all species of Pipunculus studied. Both characters are considered as intraspecific variation and the names therefore synonymized (syn. nov.). Additionally, one male and one female of P. omissinervis were cited from Mongolia by Kozánek (1992).

In Europe, P. omissinervis shows a predominantly boreo-alpine distribution—the presence in Spain indicated in De Meyer (1996 & 2005) is questioned here. The taxon should be readily collectable from southern Scandinavia up north and from the mountainous regions of western and central Europe to higher altitudes.

Towards the more continental parts of central and eastern Europe, the taxon can already be found at lower altitudes. The specimens from Great Britain (after Falk & Chandler (2005) collected in the southern half incl. Wales, north to Cheshire and Norfolk), Belgium ( De Meyer 1989b) and The Netherlands ( De Meyer & Beuk 2002), cited as P. phaeton in the past, do not fit in this pattern. With the present knowledge, they either represent an isolated population of P. omissinervis or might eventually be revealed to represent a distinct taxon.

Figures

FIGURES 36 – 42. Surstyli in strictly dorsal and outer surstylus in lateral view of male Pipunculus carlestolrai (36 & 40), Pipunculus calceatus (37 & 41) and Pipunculus omissinervis (38 – 39 & 42). Scale bars = 0.1 mm.

FIGURES 67 – 73. Ovipositor in lateral and dorsal view of female Pipunculus campestris agg. (67 – 71) and Pipunculus wolfi (72 – 73). Scale bars = 0.2 mm.

FIGURES 1 – 8. Surstyli in strictly dorsal and outer surstylus in lateral view of male Pipunculus violovitshi (1 & 5), Pipunculus elegans (2 & 6), Pipunculus oldenbergi (3 & 7) and Pipunculus zugmayeriae (4 & 8). Scale bars = 0.1 mm.

FIGURES 15 – 21. Surstyli in strictly dorsal and outer surstylus in lateral view of male Pipunculus campestris (15 & 19) and Pipunculus fonsecai (16 – 18 & 20 – 21). Scale bars = 0.1 mm.