Methocha alutacea Lin, 1966

Narita, Keisuke & Mita, Toshiharu, 2021, A review of the subfamily Methochinae from Taiwan (Hymenoptera: Tiphiidae) with description of a new species and redescription of the known species, Zootaxa 4964 (2), pp. 303-329 : 305-307

1. Methocha alutacea Lin, 1966

Figs 1–11

Methocha alutacea Lin, 1966: 186–187 . Type locality: TAIWAN: Raisha , Kaohsiung. Figs 2A, 2F, 3A, 3F .

Material examined. Type material. Holotype, ♂, Raisha , Kaohsiung, 14.iii.1924, J. Sonan leg. [ TARI] . Non-type materials. 1♂, Guizijiao, Hengchun , 14.iii.1956, K. S. Lin leg. [ TARI] ; 1♂ ( LC420051 ), N22.1317. E120.7959, Alt. 230 m, Mt. Gaoshifo-shan, Mudan , Pingtung, 19.v.2017, T. Mita leg. [ ELKU] .

Diagnosis. This species can be distinguished from other Asian Methocha species by a combination of the following characters: the distally narrowed mandible; the incurved clypeal apex; the dorsally granulate and faintly areolate propodeum; the faintly infuscate wings; the dorsally carinate hind coxa; the subapical tooth shorter than the apical one on the mandible; presence of a row of the stout setae on the posterior margin of the S2–S6 respectively; the costate anterior transverse depression of T2; the triangularly cleft distal apex of S7.

Redescription. Male.

Head ( Figs 4, 5 ). Head 0.7–0.8 times as long as wide in frontal view, temple weakly rounded in dorsal view; ocelli forming regular triangle, POL:AOL:DAO = 1.0:1.0:0.3–0.6; vertex sparsely punctate with small punctures: 1.0–4.0 puncture diameters apart, with smooth interspaces; frons more or less densely punctate: punctures 0.5–5.0 puncture diameters apart, excavated and impunctate above antennal sockets; antennal lobes developed; gena sparsely punctate; clypeus with dense small punctures with weak projection, distal apex incurved; mandible narrowed in apical half, lower tooth longer than upper one; maxillary palpus slightly longer than length of pronotum, ratio of length to width of palpomeres III–VI: 3:8–13:11–12:10; flagellum inconspicuously flattened, ratio of length to width of flagellomeres I–III: 1.4–2.5:2.4–3.5:2.7–4.

Mesosoma ( Fig 3 ). Pronotal disc punctate: punctures anteriorly larger than posteriorly, 1.0–5.0 puncture diameters apart, with smooth interspaces, anterior transverse carina absent, sometimes inconspicuously rugulose around anterior margin, lateral surface with sparse inconspicuous punctures, with smooth interspaces, lower part faintly striated; mesoscutum punctate: punctures smaller anteriorly, larger medially, surface around anterior margin coriaceous to transversely rugulose; notauli marked by transversely striated wide depression, reaching posterior twothird of mesoscutum, posterior margin of depression effaced; mesoscutellum bulging, dorsally sparsely punctate, with smooth interspaces, lateral slope smooth; mesepisternum convex, with sparse small punctures, with smooth interspaces, episternal sulcus deep, precoxal sulcus absent; metanotum elevated, smooth, laterally striated, anterior margin with deep crescentic depression; metapleural region smooth, faintly striated medially; propodeum dorsally granulate ( Fig. 6 ), sparsely or densely longitudinally striated in anterior fourth to third, partly or entirely areolate posteriorly, areolae faint, laterally punctate or punctate-rugulose, posteriorly irregularly or densely longitudinally rugose.

Legs. Hind coxa dorsally carinate and parabolically elevated in lateral view; all tarsal claws ( Fig 7 ) strongly curved on apical half, tridentate, apical tooth sharp, subapical one truncate, shorter than apical one, basal one minute, shorter than half subapical one.

Metasoma. Metasomal terga smooth, setose with sparse punctures; AMW:MTL:PMW = 1.0:2.5–3.0:2.5–2.9; T1 ( Fig 8 ) with pair of strong carina before spiracle, with several longitudinal carinae between spiracles, with smooth interspaces; anterior transverse depression of T2 costate, T3–T7 without carina, smooth; posterior margins of S2–S6 with stout setae; S7 coriaceous, with medial depression, distal apex triangularly cleft; hypopygium setose; paramere hairy around apical two-third ( Fig. 9 ), both sides rounded, dorsal margin concave around basal third, without projection; aedeagus ( Figs 10, 11 ) with cylindrical, median membranous lobe exposed dorsally.

Color. Black, except apical fourth of mandible reddish brown, maxillary palpus brown, tegula brown, wings faintly infuscate, legs brown.

Measurements. BL 5.7–8.0 mm, HL 0.8–1.1 mm, HW 1.1–1.5 mm, WF 0.5–0.7 mm, EL 0.6–0.9 mm, ML 1.7–2.7 mm, MW 0.6–0.8 mm, FWL 3.8–5.3 mm.

Female. Unknown.

Distribution. Southern Taiwan.

Figures

FIGURES 1–3. Methocha alutacea Lin, 1966, individual, male. 1 Dorsal habitus, 2 lateral habitus, 3 mesosoma, lateral view.

FIGURES 4–11. Methocha alutacea Lin, 1966, individual, male. 4 Head, frontal view, 5 head, lateral view, 6 propodeum, 7 hind tarsal claw, 8 T1, dorsal view, 9 right paramere, lateral view (right side is dorsal), 10 aedeagus, dorsal view, arrow indicating median membranous lobe, 11 aedeagus, lateral view. Scale bars are given in mm.