Methocha foveiventris 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 : 316-319

7. Methocha foveiventris Lin, 1966

Figs 59–76

Methocha foveiventris Lin, 1966: 195–199 . Type locality: Taipei. Figs 2E, 2J, 3E, 3J , 6 .

Material examined. Type material. Holotype, ♀, Taipei, 19.Oct.1955, K. S. Lin leg. [ TARI] . Non-type materials. 1♂, Taipei, 26.xi.1968, K. R. Chang leg. [ TARI] ; 1♂, Wufeng , Taichung (Malaise Trap), 23–26.iv.1979, K. C. Chou leg. [ TARI] ; 1♂: Wanfeng, Wufeng , Taichung (Malaise Trap), 22–25.v.1979, K. C. Chou leg. [ TARI] ; 1♂: Wufeng , Taichung (Malaise Trap), 26.x.–5.xi. 1979, K. C. Chou leg. [ TARI] ; 1♂: same locality, 17–22.xi.1979, K. C. Chou leg. [ TARI] .

Diagnosis. This species can be distinguished from other Asian Methocha species by a combination of the following characters: (male) the distally wide mandible; the translucent distal margin of the clypeus; the simply convex mesepisternum; the dorsally areolate, laterally transversely striate-areolate propodeum; the strongly infuscate wings; the dorsally carinate hind coxa; the basally swollen apical tooth on the tarsal claws; the subapical tooth shorter than the apical one; the basal tooth shorter than the half subapical one; the longitudinally carinate surface around a pair of the strong carina of the T1; the costate anterior transverse depression of the T2; presence of a row of the stout setae on the posterior margin of the S2–S6 respectively; the truncate posterior margin of the S7; (female) the rugulose frons; presence of the frontal tubercles; the moderately convex clypeus; the distinguishable mesoscutum and mesoscutellum from each other; the reddish brown mesosoma; the basally swollen apical tooth of the tarsal claws; the subapical tooth shorter than the apical one; the basal tooth shorter than the subapical one.

Redescription. Male.

Head ( Figs 62, 63 ). 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 = 1.0:1.0:0.5–0.6; vertex sparsely punctate: 1.0–5.0 puncture diameters apart, with smooth interspaces; frons densely punctate: punctures 0–0.5 puncture diameters apart, punctate by sparse small punctures and flat or inconspicuously excavated above antennal sockets; antennal lobes developed; gena sparsely punctate; clypeus with dense small punctures, with acute or obtuse projection, apical fifth translucent, clypeal apex truncate; mandible not distally narrowed, lower tooth longer than upper one; maxillary palpus longer than length of pronotum, ratio of length to width of palpomeres II–VI: 3:2.5–3:9–13:10:10; flagellum inconspicuously flattened, ratio of length to width of flagellomeres I–III: 1.4:1.5–2.1:1.4–2.1.

Meosoma ( Fig 61 ). Pronotal disc punctate: punctures larger or smaller, 1.0–5.0 puncture diameters apart, with smooth interspaces, anterior transverse carina absent, surface in anterior fourth to half inconspicuously transversely rugulose, punctures around posterior third smaller and sparser, with smooth interspaces, lateral surface with sparse small punctures, with smooth interspaces, lower part longitudinally striated or rugose; mesoscutum punctate: punctures larger and sparser medially, smaller and denser around anterior half, smaller and sparser around posterior half, surface around anterior fourth to third more or less transversely rugulose; notauli marked by transversely striated wide depression, reaching posterior half of mesoscutum, posterior margin of depression effaced; mesoscutellum bulging, dorsal surface punctate: punctures 1.0–6.0 puncture diameters apart, with smooth interspaces, lateral slope densely punctate: punctures 0.5–1.0 puncture diameters apart; mesepisternum convex, usually densely punctate: puncture 0.5–3.0 puncture diameters apart, episternal sulcus deep, precoxal sulcus obscure; metanotum elevated, smooth, laterally striated, anterior margin with deep crescentic depression; metapleural region smooth around anterior half, transversely striated around posterior half; propodeum ( Fig 64 ) dorsally smooth, surface around anterior fifth longitudinally striated, other part entirely areolate but sometimes irregularly transversely rugose, laterally transversely striate-areolate, posteriorly smooth, sometimes areolate, with smooth interspaces, surface around anterior half sometimes transversely rugose.

Legs. Hind coxa dorsally carinate and parabolically elevated; all tarsal claws ( Fig 65 ) strongly curved in apical half, tridentate, apical tooth sharp, basal part swollen, subapical one truncate, shorter than apical one, basal one minute, shorter than half subapical one.

Metasoma. Metasomal terga smooth with sparse punctures, setose, AMW:MTL:PMW = 1.0:3.0–3.5:2.8–3.0; T1 ( Fig 66 ) with pair of strong carina present before spiracles, longitudinally rugose between carina, sometimes median furrow deep and wide, reaching posterior third; anterior transverse depression of T2 costate, T3–T7 without carina, smooth; posterior margins of S2–S6 with row of stout setae; S7 more or less densely punctate, with coriaceous interspaces, distal margin without cleft; hypopygium longitudinally rugose, setose; paramere ( Fig 67 ) setose around apical two-third, dorsal margin substraight, ventral margin narrowed around basal third, without projection; aedeagus ( Figs 68, 69 ) with apical membranous lobe, apical hook elongate, longer than maximum width of aedeagus, faintly curved ventrally, aedeagal apodeme not curved except distal apex laterally.

Color. Black, except distal margin of clypeus translucent yellow, apical third of mandible dark reddish brown, maxillary palpus brown, tegula brown, wings strongly infuscate, legs brown.

Measurements. BL 13.0–14.0 mm, HL 1.5–1.8 mm, HW 2.0– 2.2 mm, WF 1.0– 1.1 mm, EL 1.1–1.2 mm, ML 3.6–3.8 mm, MW 1.1–1.3 mm, FWL 7.9–8.0 mm.

Female.

Head ( Figs 74, 75 ). Head 0.9 times as long as wide in frontal view; temple weakly rounded in dorsal view; ocelli forming regular triangle, POL:AOL:DAO = 1.0:1.0:0.6; vertex sparsely punctate; frons punctate: punctures larger on vertex, 2.0–5.0 puncture diameters apart, pair of frontal tubercles developed, surface above tubercles longitudinally rugose, frontal line present, reaching anterior ocellus; gena sparsely punctate; clypeus moderately convex, anterior two-third rugulose, clypeal apex rounded; mandible not distally narrowed, lower tooth longer than upper one; maxillary palpus slightly longer than pronotum, ratio of length to width of palpomeres III–VI: 3: 4:8:10; ratio of length to width of flagellomeres I–III: 2.0:1.3:1.3.

Mesosoma ( Figs 72, 73 ). Collar of pronotum dorsally costate; pronotal disc punctate; puncture 1.0–5.0 puncture diameters apart, with smooth interspaces; mesoscutum longitudinally striated; mesoscutellum smooth, elevated, rounded in profile, postero-lateral corner with deep notch; suture between mesoscutum and mesoscutellum or mesepisternum absent, almost fused but marginal region clearly marked off from them; tegula present; mesepisternum punctate by sparse small punctures, convex, forming dully corner antero-dorsally, lower part rugose; metanotum sculptured as pronotal disc, with anterior crescentic depression; metapleural region smooth; propodeum sculptured as pronotal disc.

Legs. All tarsal claws ( Fig 76 ) strongly curved in apical half, tridentate, apical tooth sharp, basally swollen, subapical one truncate, shorter than apical one, basal one minute, shorter than half subapical one.

Metasoma. Oval, polished, sparsely punctate by minute punctures; petiole longitudinally rugose.

Color. Head, flagellomeres VI–X, metasoma black, mesosoma reddish brown, tibiae and femora reddish brown to brown.

Measurements. BL 9.00 mm, HL 1.4 mm, HW 1.6 mm, WF 0.9 mm, EL 1.0 mm, ML 3.2 mm, MW 1.0 mm.

Distribution. Northern and central Taiwan.

Remarks. This is the only species that was known from both sexes before our work. Lin (1996) likely based his sex association on the body length and the habitat. We have not found any evidence to dispute this association.

Figures

FIGURES 59–61. Methocha foveiventris Lin, 1966, individual, male. 59 Dorsal habitus, 60 lateral habitus, 61 mesosoma, lateral view.

FIGURES 62–69. Methocha foveiventris Lin, 1966, individual, male. 62 Head, frontal view, the arrow indicating the translucent part, 63 head, lateral view, 64 propodeum, 65 hind tarsal claw, 66 T1, dorsal view, 67 right paramere, lateral view (right side is dorsal), 68 aedeagus, dorsal view, arrow indicating median membranous lobe, 69 aedeagus, lateral view. Scale bars are given in mm.

FIGURES 70–73. Methocha foveiventris Lin, 1966, holotype, female. 70 Dorsal habitus, 71 lateral habitus, 72 mesosoma, dorsal view, 73 mesosoma, lateral view.

FIGURES 74–76. Methocha foveiventris Lin, 1966, holotype, female. 74 Head, frontal view, 75 head, lateral view, 76 hind tarsal claw. Scale bars are given in mm.

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.