Batakomacrus caudatus (Holmgren, 1858)

Broad, Gavin R., 2010, Status of Batakomacrus Kolarov (Hymenoptera: Ichneumonidae: Orthocentrinae), with new generic combinations and description of a new species, Zootaxa 2394, pp. 51-68 : 60-62

Batakomacrus caudatus (Holmgren, 1858)

(Figs 8–12, 17, 24)

Orthocentrus caudatus Holmgren, 1858 : holotype Ƥ (NHRS) examined Orthocentrus (Stenomacrus) caudatus: Thomson, 1897 Stenomacrus caudatus: Aubert, 1981

Batakomacrus crassicaudatus Kolarov, 1986 syn. nov. Stenomacrus caudatus: Yu & Horstmann, 1997

Comments. Similar to B. flaviceps and B. noyesi , differing principally in the characters in the key. Morphology as in the generic diagnosis and description of B. noyesi (below), differences noted here. In shape and structure most similar to B. noyesi . First flagellomere of female slenderer than that of B. flaviceps (3.0–3.3 x as long as apically wide, n=4). Second metasomal tergite shiny, sculpture faint coriaceous, or occasionally distinctly pustulate; basal thyridiae inconspicuous, narrow, 2nd thyridiae faint, not raised (fig. 24); 3rd tergite onwards with pronounced, rectangular posterior emargination. Ovipositor sheaths with apical section relatively longer than in B. noyesi , setae scattered on basal half, basal stalk not visible when ovipositor at rest. Basically dark brown with reddish legs but with dull orange markings on the clypeus (or entire clypeus orange), malar space, upper edge of face, upper hind corner of pronotum and sometimes lower edge of prepectus and pronotum. The hind coxa varies from orange, slightly darker than rest of leg, to dark brown. Apical half of 1st to 3rd metasomal tergites vary from orangey-brown to dark brown. Antennae orange to midbrown, darkened apically; maxillary and labial palps off-white.

Male similar to Picrostigeus males but parameres not protruding to apex of metasoma; malar sulcus narrowly impressed (narrow but coriaceous groove present in Picrostigeus , and in this genus the parameres are large and often square-ended). Basal tergites more heavily sculptured than female, 2nd tergite with shallow diagonal grooves cutting off the anterolateral corners. Brown/black, except cream-coloured palps, entirely yellow face, reddish legs, with hind coxa brown and fore and mid coxae, trochanters, and trochantelli, creamcoloured.

Material examined. Material in BMNH (numbers of specimens in brackets) from England (45), Wales (1), Sweden (37), Finland (1), Croatia (1), Macedonia (2) and possibly Canada (see below). Material in NMS from England (2) and Scotland (57). Material in ZSMC from Bulgaria (6 specimens, type material of Batakomacrus crassicaudatus ). Listed as occurring in the following countries in Yu et al. (2005), but it is not known whether this species has been confused with B. noyesi : Azerbaijan, Bulgaria, Finland, Germany, Hungary, Lithuania, Norway, Poland, Portugal (Madeira), Russia, Sweden and UK. Collection dates for British and Swedish specimens span May to September, as follows: May 3.8%, June 7.6%, July 10.1%, August 57.0%, September 21.5%.

One female specimen from Canada was found in BMNH (Quebec, Gatineau County, Lake Duncan, VII- VIII.1979, A.C. Pont) and is only provisionally identified as B. caudatus . This Canadian specimen has a rather more pustulate sculpture to the second tergite than the majority of B. caudatus , and this tergite is square rather than transverse. It also has the metasoma more extended than any European specimens seen but this may be artefactual, resulting from the way it died. Whether these differences would stand up in a longer series remains to be tested.