Synosis parenthesellae, Broad & Shaw, 2005

Broad, Gavin R. & Shaw, Mark R., 2005, The species of four genera of Metopiinae (Hymenoptera: Ichneumonidae) in Britain, with new host records and descriptions of four new species, Journal of Natural History 39 (26), pp. 2389-2407 : 2400-2402

Synosis parenthesellae sp. n.

Female

Body length 4.8–5.2 mm. Fore wing length 3.9–4.3 mm. Antennal flagellum with 29 or 30 segments. Ocellar–ocular distance from 0.72 to 0.84 times maximum diameter of lateral ocellus ( Figures 13, 14 ). Propodeum with a short transverse carina separating the area superomedia from area basalis, area superomedia rather pointed and triangular but with more angulate sides than S. caesiellae ( Figures 1 , 15 ). Area basalis shorter with carinae forming a wider angle than in S. caesiellae and the anterior transverse carinae represented by distinct grooves, usually with a raised anterior edge (three females with a less distinct groove/ridge, very weak on one individual; one female with strong carinae with weak grooves). Malar space yellow, with a rather ill-defined edge.

Male

Body length 4.3–4.7 mm. Fore wing length 3.8–3.9 mm. Flagellum with 31 or 32 segments. Similar to the females but with yellow of the face not extending beyond the anterior tentorial pits. The grooves replacing the anterior transverse carinae of the propodeum are very well developed in the two male specimens known ( Figure 1 ).

Comments

Separated from S. caesiellae by the greater number of flagellar segments and rather subtle differences in the shape of the propodeal areas demarked by carinae, as detailed in the description above. One non-reared male (from Savernake, see ‘‘Material examined’’) differs in that the malar space is yellow, as in females. This specimen is tentatively assigned to S. parenthesellae but is not included in the type series as it differs slightly in appearance and is from a different locality. One reared male, and some males of S. caesiellae , have the malar space faintly marked with yellow so the un-reared specimen may be at the extreme of a trend.

Material examined

Holotype: ♀, ‘‘Rowardennan, Loch Lomond [ Scotland, UK] ex Ypsolopha parenthesella , larva below Quercus 27.6.1983, em. 6.6.1984 (M.R. Shaw)’’ (NMS). Paratypes (all NMS): 3♀♀, same details as above except em. 8 August 1983, 14 August 1983, and 8 June 1984; 2 „„, same details as above except em. 23 May 1984 and 6 June 1984. Other material: 1 „, England: Savernake Forest, Wilts., SU 229656, Malaise trap, 23 May–13 June 1990 (K. Porter) (NMS).

Biology

All of the type specimens were reared from pupae of Ypsolopha parenthesella (Linnaeus) ( Lepidoptera : Yponomeutidae ) collected as fully fed larvae by sweeping grasses below Quercus in June, at a single site. Four adults emerged in May and June the following year but two emerged in August of the year of collection.

Etymology

This species is named after the yponomeutid species from which it has been reared.

Figures

Figure 1. Propodeum of Synosis parenthesellae „, with carinae and areas marked.

Figures 13–15. Synosis parenthesellae. (13) ♀, dorsal view of head showing ocelli. (14) „, dorsal view of head showing ocelli. (15) ♀, propodeum.