Calosota vernalis Curtis

Gary A. P., Gibson, 2010, Calosota Curtis (Hymenoptera, Chalcidoidea, Eupelmidae) - review of the New World and European fauna including revision of species from the West Indies and Central and North America, ZooKeys 55, pp. 1-75 : 53-55

Calosota vernalis Curtis Figs 327325469, 73

Calosota vernalis Curtis 1836: folio 596. Type data: England: Southgate. Lectotype ♀ (MVMA; not examined), designated by Graham 1969: 90.

Calosoter aestivalis Walker 1837: 359-360. Type data: England: near London. Syntypes, ♀ and ♂ (BMNH, type no. 5.1620; not examined). Synonymy by Graham 1969: 90. Homonym of Calosota aestivalis Curtis (1836).

Diagnosis.

FEMALE (Fig. 32) and MALE. Head (Figs 3, 69) with frontovertex finely, meshlike coriaceous or at most only very shallowly reticulate in small part, but scrobal depression quite distinctly reticulate to transversely reticulate-alutaceous excluding smooth and shiny scrobes; ocelli in acute triangle with POL subequal to or only slightly greater than OOL; mesonotum (Figs 27, 73) meshlike reticulate and uniformly dark to bluish-green or depressed medial part of mesoscutum and scutellum dark or sometimes with slight coppery luster under some angles of light; axilla elongate-slender, sculptured surface usually mostly obliquely angled rather than a flat dorsal surface and separated by at least about 6 × own width (Figs 27, 73); fore wing hyaline, without linea calva or speculum; acropleuron finely, obliquely coriaceous-alutaceous anteriorly and longitudinally coriaceous-alutaceous to very finely alutaceous-aciculate posteriorly (Fig. 54); lower mesepimeron reduced (Fig. 54).

Male with at least fl2−fl6 longer than wide and quite densely setose with short, only slightly curved setae projecting at about a 45° or lesser angle relative to the flagellomere.

Biology.

A gregarious ectoparasitoid of Trichodes Herbst ( Coleoptera : Cleridae ) in Megachilidae and Sphecidae nests ( Thompson 1955 (as Calosota aestivalis ); Askew and Nieves-Aldrey 2006). The host species in Buprestidae and Curculionidae , and possibly Scolytidae ( Coleoptera ), listed by Noyes (2003) almost certainly refer to Calosota aestivalis . All the original publications cited by Herting (1973) for the various host species were published prior to Graham (1969), who corrected the previously reversed concepts of Calosota aestivalis and Calosota vernalis . Furthermore, even the more recent publications listing Blastophagus minor (Hartig) ( Scolytidae ) as a host cited Hedqvist (1963), who interpreted Calosota vernalis in the sense of Calosota aestivalis . However, a single male from France (BMNH) is labeled "ex Pinus sylvestris with scolytids".

Regional material examined.

None, but one female (CNC Photo 2009-43, CNC SEM 2009-47) and male labeled: Canada: BC [British Columbia], Surrey, Westcoast Granite, CFS [Canadian Forest Service] 1988-0035-07, quarantine interception, ex log bolt #24 from Norway, em. 20.VII.1988.

Distribution.

Noyes (2003) listed Calosota vernalis from several countries in the Palaearctic region; I saw specimens from England (BMNH), France (BMNH), Italy (CNC, CNC SEM 2009-46), Spain (CNC, MNCN), Sweden (CNC), and Yugoslavia (BMNH).

Recognition.

Additional features than those used in the key to differentiate Calosota vernalis relative to Calosota aestivalis are provided by Graham (1969), including comparatively narrower axillae and the acropleuron anteriorly being obliquely coriaceous-alutaceous (Fig. 54) rather than at least shallowly meshlike reticulate (Fig. 55). If eventually collected in North America, individuals of Calosota vernalis are most likely to be misidentified as one of the four regional species having a conspicuously sculptured scrobal depression, but unlike any of these species lack an exposed lower mesepimeron (Fig. 54). It also uniquely has an unusual sculpture combination of a finely meshlike coriaceous frontovertex and more coarsely reticulate or at least transversely sculptured scrobal depression (Figs 3, 69). This not only helps differentiate it from Calosota aestivalis , which has both the frontovertex and scrobal depression reticulate (Fig. 2), but also from the nominal European species Calosota agrili Nikol’skaya (1952) (paratype examined, BMNH), Calosota bolivari Askew (2006) (holotype examined, MNCN) and Calosota nitens Askew (2006) (holotype and paratype examined, MNCN), which have the frontovertex coriaceous and the scrobal depression mostly smooth and shiny similar to the New World albipalpus species-group (cf. Figs 9, 10, 66).

Askew and Nieves-Aldrey (2006) noted that the unknown male of Calosota nitens may have the antennal features that they used to differentiate males of Calosota vernalis . The male of Calosota nitens is undescribed and I have not seen any males resembling females of the species. However, based on the two examined type females from Spain and one additional female from Sardinia (BMNH), in addition to having the outer surface of the metacoxa entirely setose, females of Calosota nitens uniquelyhave the propodeal callus setose along the propodeal foramen. Other Calosota typically have the callus setose lateral to the spiracle and sometimes there are 1 or 2 setae behind the spiracle but never along the propodeal foramen. The male of Calosota nitens may also have the propodeum at least sparsely setose along the foramen and if so should be recognized easily.

Although the male of Calosota bolivari is also undescribed, I saw 19 males and 3 females from Spain (CNC, MNCN), 13 males and 3 females from Cyprus (CNC), and 1 male from Corsica (ZSMC) that I identify as this species. The combination of head sculpture (upper part of scrobal depression at most finely coriaceous rather than obviously reticulate) and exposed, lunate lower mesepimeron differentiate the males from those of Calosota aestivalis and Calosota vernalis , respectively. Flagellar structure of Calosota bolivari males is somewhat similar to that of Calosota vernalis , but the funiculars are typically shorter and the setae are conspicuously longer and more distinctly curved, the setae projecting at an obtuse angle and curved so as to be subparallel with the funicular distally. Using Askew and Nieves-Aldrey (2006), the putative males of Calosota bolivari key to Calosota obscura and Calosota aestivalis , but the flagellum is comparatively more gracile with abutting funiculars unlike that described for Calosota obscura , and the acropleuron is finely coriaceous. Of the six females examined, one (El Ventorrillo, 14.VII.91, A. Garrido) was identified as Calosota dusmeti in Askew and Nieves-Aldrey (2006). This apparent misidentification likely was in part because it has about the basal two-thirds of the scape yellowish-orange, unlike the holotype of Calosota bolivari which has an entirely dark scape, but similar to specimens of Calosota dusmeti . However, scape color of other females from Spain and Cyprus, which vary in length from about 2.4−5 mm, varies from entirely or virtually entirely dark to variably extensively yellowish. These females are also very similar to the paratype of Calosota agrili examined, which has about the basal half of the right scape yellowish and the left scape quite dark with only some indication of yellow in its basal half. Another female from Voronezhskaya Oblast, Russia (CNC), identified as Calosota agrili by A. Sharkov has both scapes dark. All the females have the marginal vein about 2.8 × as long as the stigmal vein and the carina along the propodeal foramen not quite extending to the anterior margin of the propodeum so that there is a very short medial plical region similar to the holotype of Calosota bolivari . The holotype was described as having the medial length of the propodeum (including plical region and smooth and shiny lunate region posterior to carina extending anteriorly from along foramen) as long as the dorsellum, but this is partly an artifact because the mesonotum is arched and the anterior margin of the propodeum extends over the apex of the dorsellum to reduce its apparent length. Based on the above, I suspect that Calosota bolivari is a junior synonym of Calosota agrili , but hesitate to formalize the synonymy prior to a more comprehensive revision of Palaearctic Calosota .