Brachycyrtus cerrettii Di Giovanni, 2021

Giovanni, Filippo Di & Varga, Oleksandr, 2021, First record of the subfamily Brachycyrtinae (Hymenoptera, Ichneumonidae) from continental Africa, with description of three new species, Zootaxa 4985 (2), pp. 203-218 : 208-211

Brachycyrtus cerrettii Di Giovanni , sp. n.

( Figs 3A–C , 4A–F )

urn:lsid:zoobank.org:act:4052A81A-1555-4172-A048-5449BC3C8278

Material examined. Holotype: ♀, “ UGANDA / Kibale National Park / Kanyawara Biol. Station / 23– 30.01.2011 / leg. S. Katusabe & Co. // Malaise trap (2) / Alt. 1510 m / 00:33:55,6N 30:21:29E // TUZ023081 ” ( TUZ).

Description. Female, holotype. Body length about 5.0 mm. Fore wing length about 4.1 mm. Body with a moderately dense covering of short, fine, white setae.

Head ( Figs 3 A–C , 4A ). Face about 0.9× as high as maximum wide; face polished, with just few discernible but shallow punctures; clypeus smooth, shining and without punctures, apical margin evenly and gently curved; malar space about 0.4× as basal width of mandible; mandible smooth and impunctate; eye strongly emarginate opposite antennal socket; vertex, temple and gena polished, with inconspicuous punctures; temple strongly narrowed behind eye (in dorsal view), gena about 0.35× as transverse diameter of eye (in lateral view); occipital carina strongly marked ventrally, joining hypostomal carina above mandible base, hypostomal carina slightly elevated; ocularocellar distance about 0.8× the maximum diameter of posterior ocellus, about 0.5× the distance between posterior ocelli; flagellum with 31 flagellomeres, with last nine flagellomeres just slightly enlarged; first flagellomere about 4.5–5.0× as apically wide, second flagellomere 3.2–3.5× as apically wide.

Mesosoma ( Figs 3C , 4A, 4C ). Pronotum polished, with inconspicuous punctures on posterior upper hind corner; epomia straight, flange-like and extending to dorsal edge; pronotum with few small wrinkles on ventral corner between epomia and posterior margin. Mesoscutum subpolished, strongly punctate, punctures denser in the center and near anterior margin; notauli absent; scuto-scutellar groove with inconspicuous longitudinal ridges; scutellum subpolished, with dense but shallow punctures; scutellum with carinae extending to about 0.6–0.7× of its length. Mesopleuron with dense punctures on anterior and on ventral half, on posterior half polished and without punctures or striae, except for few small striae just below speculum; sternaulus as a shallow groove extending approximately to half of mesopleuron, straight; epicnemial carina present, ending opposite to ventral angle of pronotum, epicnemial carina strongly elevated ventrally in the middle, between fore coxae; posterior transverse carina of mesosternum absent at the level of mid coxae, present medially. Metapleuron polished, with small punctures along anterior and posterior margins, centrally with just few isolated punctures. Propodeum subpolished; anterior transverse carina complete; area basalis obliterated, with a short longitudinal carina joining anterior transverse carina and anterior margin of propodeum; posterior transverse carina complete laterally but absent medially, thus area superomedia and area petiolaris joined; area superomedia smooth and polished centrally, with small transverse striae along margins, area petiolaris with strong transverse striae; area externa with few shallow punctures; area dentipara with few inconspicuous and isolated punctures on polished surface; area lateralis with shallow punctures on polished surface; pleural carina complete; propodeal spiracle sub-oval.

Wings ( Figs 3A , 4E ). Fore wing with 1cu-a distal to M&RS by about 0.6× the length of 1cu-a; 2rs-m about 0.3× as the section of 1m-cu&M between 2rs-m and 2m-cu. Hind wing with abscissa of CU present but spectral, CU about 1.3× as cu-a (i.e., nervellus intercepted below the middle in Townes’ morphological nomenclature).

Metasoma ( Figs 4B, 4D, 4F ). Polished with fine setiferous punctures on postpetiole and all metasomal tergites; metasomal tergite II with thyridia present, oblique; tergite II about 2.1–2.2× as apically wide, and about 0.8× the length of tergite I; metasomal tergites II–IV with a large oval to sub-oval membranous area in the center of the tergite. Ovipositor sheath about 1.4× as hind tibia; ovipositor strongly decurved.

Colour. Face, clypeus, gena, mandible except teeth, palpi, outer side of scape light yellow; area behind antennal base, vertex, occiput black (black areas connected); teeth and inner side of scape reddish–brown; antenna yellowish basally, yellowish–brown medially, reddish–brown apically, last segments brown. Mesosoma black and yellow; pronotum and propleuron pale yellow, propleuron with dark marks on ventral margin just above fore coxa; mesoscutum black with a squared yellow spot posteriorly in the middle and two yellow hook-like marks on shoulders, central black band of mesoscutum extending to posterior central margin of pronotum; scuto-scutellar groove and suture between scutellum and postscutellum black, scutellum basally and medially black, apically and laterally yellow, postscutellum yellow; tegula yellowish–brown; mesopleuron black, except for subalar prominence and for a diagonal band running from dorsal anterior margin of mesopleuron to the center of mesopleuron pale yellow; metapleuron pale yellow, anterior margin and ventral margin just above hind coxae black; propodeum pale yellow, area of propodeum anterior to anterior transverse carina black. Fore and mid coxae, trochanters and trochantelli pale yellow; fore femur and tibia pale yellow, with yellowish–brown marks dorsally; fore and mid tarsi yellowish–brown; hind coxa mostly black, with pale yellow marks; hind tronchantellus and hind femur pale yellow, hind trochanter and longitudinal stripes along inner and outer sides of hind femur dark brown; hind tibia dark brown, slightly lighter subbasally and on the outer side; hind tarsi brown. Metasomal tergite I black with pale yellow band apically; metasomal tergite II black on the basal 0.75, reddish apically and on lateral margins; metasomal tergite III black on basal half, yellowish–red on apical half; following metasomal tergites yellowish–red. Veins and pterostigma reddish–brown. Ovipositor sheaths brown.

Male. Unknown.

Biology. Unknown.

Differential diagnosis. Brachycyrtus cerrettii sp. n. can be distinguished from all the other species of the genus by the unusual presence of large oval to sub-oval membranous area in the center of the metasomal tergites II–IV and strongly decurved ovipositor. In addition, it can be distinguished by the combination of the following characters: eye strongly emarginate opposite antennal socket; flagellum with 31 flagellomeres, with last nine flagellomeres just slightly enlarged; gena about 0.35× as transverse diameter of eye (in lateral view); occipital carina joining hypostomal carina above mandible base; scuto-scutellar groove with inconspicuous longitudinal ridges; posterior half of mesopleuron polished and without punctures or striae, except for few small striae just below speculum; epicnemial carina strongly elevated ventrally in the middle, between fore coxae; metapleuron centrally polished and with just few isolated punctures; propodeum with area superomedia and area petiolaris joined, area superomedia polished centrally, with small transverse striae along margins, and area petiolaris with strong transverse striae; fore wing with 1cu-a distal to M&RS and 2rs-m about 0.3× as long as the section of 1m-cu&M between 2rs-m and 2m-cu; hind wing with nervellus intercepted below the middle; metasomal tergite II with thyridia present; metasomal tergite I black with pale yellow band apically; metasomal tergite II and III black basally, yellowish–red apically, following metasomal tergites yellowish–red.

Distribution. Uganda, known only from the holotype.

Etymology. The new species is named in honour of Prof. Pierfilippo Cerretti, a renowned expert of Diptera Tachinidae and Rhinophoridae , who was the supervisor of the first author during his Ph.D and spent years working on the Afrotropical flies.

Figures

FIGURE 3. Brachycyrtus cerrettii Di Giovanni, sp. n., female, holotype. A: habitus, lateral view. B: face, frontal view. C: temple and mesoscutum, dorsal view.

FIGURE 4. Brachycyrtus cerrettii Di Giovanni, sp. n., female, holotype. A: mesopleuron and metapleuron, lateral view. B: metasomal tergites II and III, dorsal view. C: propodeum, dorsolateral view. D: metasomal tergites II and III, dorsolateral view. E: wings, lateral view. F: ovipositor, lateral view.