Syrphoctonus desvignesii
Creators: name: Klopfstein, Seraina
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Ichneumonidae
Syrphoctonus
Syrphoctonus desvignesii

description: Syrphoctonus desvignesii (Marshall 1870, Bassus) (stat. rev.)
(new name for Bassus pulchellus Desvignes)
Bassus pulchellus Desvignes 1862 (junior homonym)
Homotropus fraudulentus recurvatus Dasch 1964a (syn. nov.)
Homotropus neopulcher Horstmann 1968 (syn. nov.)
Diagnosis. Fore wing length 4.3–5.2 mm. Antenna in females with 19–21 flagellomeres, in males with 20–21 flagellomeres, with tyloids on flagellomeres 6 to 15/16. Epicnemial carina sometimes only weakly interrupted behind fore coxa. Mesoscutum with weak and sparse punctures on a finely coriaceous background. Propodeum almost devoid of carinae, at most with pleural carina and apex of lateral longitudinal carina weakly indicated, sculpture coriaceous and matt. Female metasoma compressed posterior to fourth tergite or rather gradually tapered to apex, first tergite 1.3–1.4 times longer than wide in females, 1.4–1.7 in males; spiracle of third tergite on or below lateral fold.
Colouration of females. Antenna dark brown, paler below. Head and mesosoma black, face with a yellow central face patch, yellow on clypeus, mouthparts, hind corner of pronotum, tegula, subtegular ridge, large shoulder mark, upper mesepimeron, and most of scutellum. Legs orange, fore and mid coxae black basally with a yellow apex, hind coxa black, trochanters yellow; femora orange, often marked with black ventro-basally; hind tibia orange with a dark apex, tarsus dark. Metasoma usually orange on hind margin of tergite 2 and entire tergites 3 and sometimes 4, this colouration sometimes dark, and usually with posterior margins of tergites 3 to 5 yellow.
Colouration of males. As in females but with yellow ventrally on antenna, entire face, lower propleuron, epicnemium, and a stripe on lower mesopleuron. Fore and mid coxae entirely yellow, hind coxa black with a yellow apex. Metasoma sometimes as in females but often with orange colouration reduced, yellow posterior margins of tergites 3 to 5 often broadened.
Material examined. Holotype of Bassus pulchellus Desvignes: United Kingdom, 1♂, at BMNH. Paratypes of Homotropus fraudulentus recurvatus Dasch: USA, California, Crane Flat, Yosemite park, leg. H.M.G., D. & J. Townes, 22.VII.1948, 1♂ at BMNH; 25.VII.1948, 1♀, at AEI. USA, California, Cisco, leg. H.M.G. & D. Townes, 31.VII.1948. 1♂, at AEI. Paratype of Homotropus neopulcher Horstmann: Sweden. 1♀, at ZIL.
New for Italy: Südtirol, Antholzer-Obertal, 1800m, leg. E.Diller, 19.VIII.1967. 1♀, at ZSM.
Finland (1), Germany (2), Ireland (1), Italy (1), Norway (1), Sweden (10), Switzerland (20), United Kingdom (1), USA (4).
Distribution. Western Palaearctic and Nearctic.
Figures. Habitus (Fig. 34 D).
Notes. This species had been synonymized with S. tarsatorius (Morley 1911), but is actually conspecific with the taxon referred to as Homotropus neopulcher Horstmann, which becomes a junior synonym. As I have only seen the paratypes of Homotropus fraudulentus recurvatus Dasch and not of the subspecies fraudulentus, only the former is synonymized with desvignesii here. Whether H. fraudulentus should be treated as a distinct species, as a subspecies of desvignesii, or even as its synonym thus remains unclear at the current state.
description: Published as part of Klopfstein, Seraina, 2014, Revision of the Western Palaearctic Diplazontinae (Hymenoptera, Ichneumonidae), pp. 1-143 in Zootaxa 3801 (1) on pages 95-97, DOI: 10.11646/zootaxa.3801.1.1, http://zenodo.org/record/249944