Torymus sasae Matsuo, 2020

Matsuo, Kazunori, 2020, A revision of Japanese Torymus Dalman (Hymenoptera: Torymidae), Zootaxa 4758 (3), pp. 401-441 : 430-432

Torymus sasae Matsuo n. sp.

Figs 4a , 7 c–d, 20a–d, 25d

Etymology. The specific name, sasae , is derived from the host plant of the host insect.

Type material. Holotype: ♀ ( BLKU), emerged on 23 May 2003 from a gall of Procystiphora uedai on Sasa nipponica collected by A. Ueda on 24 April 2003 from Mt. Odaigahara, Kamikitayama, Nara, Japan. Paratypes: 7 ♀ and 5 ♂, same data as the holotype ( BLKU).

Description. Female. Body length excluding ovipositor sheath 2.6–2.9 mm. Head bluish green. Scape yellow-

ish brown but darker apically; pedicel and flagellum brown. Mesosoma bluish green. Fore wing hyaline. Fore coxa yellow; mid and hind coxae concolorous with mesosoma; all femora and tibiae yellow. Metasoma bluish green ( Fig. 4a ).

Head 2.0–2.1× as wide as long in dorsal view; temple 0.2× as long as dorsal length of eye; POL 2.0–2.2× OOL; OOL 1.0× OD. Head 1.2–1.3× as wide as high in frontal view ( Fig. 20a ); eyes separated by 0.9–1.0× their height; malar space 0.3× height of eye; mouth 2.2× malar space; clypeus with apical margin produced, truncate medially. Antenna not clearly clavate ( Fig. 7c ); scape 0.6× as long as height of eye, just reaching ventral margin of anterior ocellus; combined length of pedicel and flagellum 1.2–1.3× width of head; pedicel 1.5–1.6× as long as wide; anellus 1.2–1.5× as wide as long; F1 1.2× as long as wide, shorter than pedicel; F2–F5 1.1–1.2× as long as wide; F6–F7 quadrate; each funicular segment bearing longitudinal sensilla arranged in two rows; C3 with a small tuft of micropilosity beneath.

Mesosoma 1.8× as long as wide; mesoscutum ( Fig. 20b ) with small piliferous punctures; sculpture on mesoscutum in anterior half transversely reticulate; notaulus shallow; scutellum ( Fig. 20c ) 1.3× as long as wide, sculptured as posterior part of mesoscutum; dorsellum without median carina; propodeum ( Fig. 20d ) with superficial reticulation, smoother medially; lower mesepimeron 1.3–1.5× as long as wide. Fore wing ( Fig. 25d ) 2.4× as long as wide; costal cell 9.0–10.1× as long as wide, on upper surface with a setal row, on lower surface with a complete setal row and scattered setae; basal cell closed, with a setal row below submarginal vein; cubital setal line present; basal setal line present; speculum narrowly opened below; relative lengths of marginal vein: postmarginal vein: stigmal vein=12.4: 2.8: 1.0. Hind coxa 1.8–2.0× as long as wide, with dorsal carina basally; dorsal surface of hind coxa setose in basal half; hind femur 4.2–4.5× as long as wide; hind tibia with longer spur 1.4–1.5× as long as width of hind tibia, 0.4–0.5× length of basitarsus; shorter spur 0.6–0.7× length of longer spur.

Metasoma as long as mesosoma; posterior margin of metasomal tergum five incised; tip of hypopygium situated at 0.6 length of metasoma; ovipositor sheath as long as metasoma plus 2/3 mesosoma, 2.3× as long as hind tibia.

Male. Differs from female as follows. Body length 2.5 mm. Antenna stouter than that of female ( Fig. 7d ); scape bluish green; pedicel about 1.1× as long as wide; anellus transverse, 2.5 as wide as long; F1–F3 quadrate; F4–F6 0.9× as long as wide; F7 0.8× as long as wide; longitudinal sensilla on each funicular segment arranged in one row. Relative lengths of marginal vein: postmarginal vein: stigmal vein=10.0: 2.3: 1.0. Hind tibia with longer spur 0.7× length of basitarsus. Metasoma with coppery tint; posterior margin of metasomal tergum five entire.

Distribution. Japan (Honshu).

Host information. Torymus sasae is a parasitoid of Procystiphora uedai Sato and Yukawa ( Diptera : Cecidomyiidae ) that induces galls on Sasa nipponica (Makino) Makino et Shibata (Poaceae) (gall photo: fig. 14 of Sato et al. 2009).

Remarks. Females of T. sasae are similar to T. fractiosus Graham and Gijswijt , which is recorded from France ( Graham & Gijswijt 1998), by having the following shared features: POL 2.0–2.2× OOL; OOL 1.0× OD; malar space 0.3× height of eye; mouth 2.2× malar space; dorsellum without median carina; dorsal surface of hind coxa with setae in basal half; hind tibia with longer spur 0.4–0.5× length of basitarsus; ovipositor sheath 2.3× as long as hind tibia. However, females of T. sasae can be distinguished from T. fractiosus by the basal cell of the fore wing with a setal row below the submarginal vein (bare or 2–3 setae in T. fractiosus ).

Figures

FIGURE 4 a–d. ♀, lateral view. a, T. sasae; b, T. sawadai; c, T. sinensis; d, T. wanggyui.

FIGURE 7 a–h. Antenna. a, T. rugosus ♀; b, T. rugosus ♂; c, T. sasae ♀; d, T. sasae ♂; e, T. sawadai ♀; f, T. sawadai ♂; g, T. wanggyui ♀; h, T. wanggyui ♂. Scale lines 0.25 mm.

FIGURE 20 a–d. T. sasae ♀. a, head, frontal view; b, mesoscutum, dorsal view; c, scutellum, dorsal view; d, propodeum, dorsal view.

FIGURE 25 a–f. ♀ fore wing upper surface. a, T. minamii; b, T. quernus; c, T. rugosus; d, T. sasae; e, T. sawadai; f, T. wanggyui. Scale lines 0.5 mm.