Cotesia radiantis (Wilkinson, 1929)

Fig. 24

Apanteles radiantis Wilkinson, 1929: 110 (holotype, ♀, NHMUK).

Cotesia radiantis – Austin & Dangerfield 1992: 22 (transfer from Apanteles s.l.).

Diagnosis

Cotesia radiantis can be separated from all other species of Cotesia currently described from Australia and Papua New Guinea by the following combination of characters: T1 broadening posteriorly, wedge shaped; fore wing vein r shorter than 2RS; anteromesoscutum sculpturing considerably stronger along lines of notauli than elsewhere, almost smooth laterally – basal area of anteromesoscutum almost reticulate rugose; scutellar disk with shallow punctures; mesosoma not dorsoventrally flattened; hind coxa and metasoma only slightly paler than mesosoma; ocelli normal sized, OOL/posterior ocellus diameter <2.4.

Material examined

Holotype

AUSTRALIA • ♀; Queensland, Gatton; 3 Dec. 1925; E. Ballard leg.; ex. larvae of “ Euxoa radians ” attacking cotton seedlings; NHMUK 3.c.1036.

Redescription

Female (from holotype)

COLOUR. Head, antenna and mesosoma dark, T1–2 dark, rest of dorsal metasoma pale on non-sclerotised areas with dark sclerotised areas, pale laterally at anterior end, darkening posteriorly; (fore-, mid-, hind coxa) dark, dark, dark; femora (fore-, mid-, hind femur) pale, pale, light brown; tibiae (fore-, mid-, hind tibia) pale, pale, light brown; tegula and humeral complex pale to light brown; pterostigma light brown; fore wing veins light brown.

BODY LENGTH. Head to apex of metasoma: 2.3 mm.

HEAD. Antenna broken in types; OOL/posterior ocellus diameter 2.2; POL/posterior ocellus diameter 2.3; antennal flagellomere 2 length/width 2.8; antennal flagellomere 14 length/width 1.4.

MESOSOMA.Anteromesoscutum punctate reticulate, much smother on lateral edges with deep sculpturing along lines of the notauli, posterior quarter of anteromesoscutum with sculpturing tending towards reticulate rugose; number of pits in scutoscutellar sulcus 11; scutellar disc with shallow punctures; mesoscutellum hidden by wings in type.

WINGS. Fore wing length 2.2 mm; length of veins r/2RS 0.6; length of veins 2RS/2M 1.5; length of veins 2M/(RS+M)b 0.9; pterostigma length/width 2.8.

LEGS. Hind tibia inner spur length/metabasitarsus length 0.5.

PROPODEUM. Medial carina present but barely distinguishable amongst strong rugose sculpturing.

METASOMA. T1 partially hidden by wings in type, broadening posteriorly, wedge shaped, length unable to be measured, reticulate rugose in posterior third, posterior edge with some striate sculpturing; T2 width at posterior margin/T2 length 2.5, rectangular, lateral sides slightly curved, irregularly striate sculpturing tending towards rugose in some parts; border between T2 and T3 straight, slightly indented, T2 length /T3 length 0.7; T3 sculpture smooth and shiny; ovipositor sheaths length/hind tibial length 0.13.

Male

Not examined, male included in the original description of Wilkinson as not remarkably different from female type.

Distribution

Only known from type locality in south-eastern Queensland.

Host

Agrotis munda (Walker, 1857) (Noctuidae). Record from type specimens. Note that the host name given in the original description is Euxoa radians Guénée, 1852, but that the actual host is not conspecific with Agrotis radians Guénée, 1852 due to confusion historically in the Australian literature. See Common (1958) for details. Gregarious (based on multiple specimens from description with identical label data).

Remarks

There are a large number of specimens sequenced as part of this project (BIN: BOLD:ABA6232, Fig. 1) that are broadly distributed across Australia and that strongly resemble C. radiantis. As this group of specimens cannot be separated definitively from the holotype of C. radiantis, we do not describe them as a new species, but also hesitate to confirm their identity as C. radiantis until a specimen reared from Agrotis munda is sequenced and the COI barcode compared (no attempt was made to extract DNA from the holotype of C. radiantis).