Dimophora ­­­Förster

Omatsu, Yuji & Kazuhiko Konishi, 2023, Revision of the genus Dimophora Förster (Hymenoptera: Ichneumonidae: Cremastinae) from Japan, Zootaxa 5278 (3), pp. 537-554 : 538-539

Genus­­­ Dimophora ­­­Förster ­­­

Dimophora Förster; 1869: 155 .

Type-species: Dimophora robusta Brischke [= nitens Gravenhorst 1829b ], by subsequent inclusion (Brischke, 1894: 55).

Dimophorus Thomson, 1889: 1355–1356 . [Unjustfied emendation.]

Olidotmema Cushman, 1920: 280. Type-species: Oligotmema prima Cushman [= evanialis Gravenhorst 1829a ], by original designation.

Diagonosis.­­­ Referring to Dasch (1979), Gauld (2000) and Townes (1971). Small to moderately sized species, four wing length 2.4–7.2 mm. Head with occipital carina complete, or narrowly interrupted medially; frons without a median horn; mandible with upper tooth shorter than lower tooth, or teeth subequal; maxillary and labial palpi with 5 and 4 segments respectively. Mesosoma not particularly elongate; pronotum unspecialized, with epomia lacking or weak; mesoscutum with notauli quite shallowly impressed; ­­­ scutellum weakly convex; propodeum with anterior and posterior transverse carinae present, more or less complete, lateromedian and lateral longitudinal carinae more or less complete between the transverse carinae.

Fore wing with areolet, triangular, trapezoidal or pentagonal. Hind wing with 2nd abscissas of CU and AA weak or absent, arising from below middle of nervellus when present.

Legs with tarsal claws unspecialized; mid and hind tibia with two apical spurs; hind femur without a ventral tooth.

Metasoma with lower margins of T1 widely separated, the first sternite visible between them; T1 with glymma; T2 without thyridium; ovipositor usually straight or apically downcurved; genitalia simple, without lobe or tooth.

Description­­­based­­­on­­­Japanese­­­species

Body length ­­­ about 2.7–6.9 mm. Head­­­ 1.1–1.4 times as wide as high, face 1.7–2.6 times as wide as high, head 1.8–2.5 times as wide as face; granulate with dense setae; area between eye and antennal base flat, without protrusion; eye not covered with short setae; POL/OD=1.2–1.8, OOL/OD=0.8–1.4, wide of temple/OD=1.5–2.2; clypeus 1.4–2.2 as long as wide; malar space 0.4–0.9 times as long as basal mandibular width; antenna with 24–35 flagellomeres; 1st fragellomere 1.0–1.5 times as long as 2nd, 3.2–4.7 as long as wide. Mesosoma puncto-strigose with dense setae; not particularly elongate, 1.4–1.7 times as long as high; mesoscutum 0.9–1.1 times as long as wide; scutellum 0.6–1.1 times as long as wide; axilla with carina of posterior margin broadened to form raised subtriangular smooth area (Figs 9, 18, 24); speculum bald and glossy; propodeum with area superomedia 0.4–0.7 as long as area petiolaris. Wings­­­ with densely setae, hyaline and tinged with pale brown to brown. Fore wing 2.4–4.9 mm long, 2.3–3.0 as long as wide; stigma moderately wide, 2.1–2.9 times as long as wide; areolet oblique to rhombic, 0.6–1.0 times as long as wide. Hind wing with 5 or 6 distal hamuli. Metasoma granulate and sparsely punctate with setae; T1 0.6–1.4 mm long, 2.1–2.9 as long as wide, 1.3–2.2 times as long as T2; petiole 1.1–1.8 times as long as postpetiole; T2 0.4–0.8 mm long, 0.6–1.1 times as long as wide; from the T3 almost smooth, faintly coriaseous. Ovipositor­­­down-curved, with a dorsal subapical notch, ­­­ 1.1–2.7 mm long, 2.2–2.5 times as long as hind 1st tarsomere. Male­­­genitalia.­­­ Paramere (Figs 19, 22) with setae and a wide notch on dorso-apical margin; digitus tapering toward pointed apex; cuspis parallel sided with rounded apical margin; aedeagus (Figs 20, 23) less slender; penis valve with spines on mesad surface of subapical portion and ventral edge (Figs 21, 24).

Bionomics. No additional records of hosts.

Remarks. In Japan, Dimophora can be easily distinguished from other genera of Cremastinae by having areolet on fore wing.

Dasch (1979) stated that “[propodeum with] lateral longitudinal carinae more or less complete between the transverse carinae”, however, posterior half of the carinae (lateral longitudinal carina in area dentipara) is missing in D. parva (Fig. 31).