Metopiinae, Forster, 1869

Ranjith, A. P. & Priyadarsanan, Dharma Rajan, 2022, A new Darwin wasp genus, Soliga (Hymenoptera: Ichneumonidae: Metopiinae), from India, European Journal of Taxonomy 852 (1), pp. 57-76 : 59-66

Key to the Indo-Australian genera of Metopiinae

1. Face generally flat, with a large shield-shaped region bounded by a carina ( Fig. 1a ); mid tibia with one apical spur ............................................................................................... Metopius Panzer, 1806

– Face entirely convex, lacking a shield-shaped region bounded by a carina ( Fig. 1b ); number of mid tibial spurs variable ........................................................................................................................... 2

2. Metasomal tergites 3–5 without laterotergites ( Fig. 2a ) ................................................................... 3

– Metasomal tergites 3–5 with laterotergites ( Fig. 2b ) ........................................................................ 5

3. Areolet present ( Fig. 3a ); metasoma clavate, fifth and sixth segments much wider than preceding segments ( Fig. 3b ); mid tibia of male with one spur ( Fig. 3c ) .................. Acerataspis Uchida, 1934

– Areolet absent ( Fig. 3d ); metasoma parallel sided, fifth and sixth segments not wider than preceding segments ( Fig. 3e ); mid tibia of male with two spurs ( Fig. 3f ) ........................................................ 4

4. Mesopleuron with sulcus ( Fig. 4a ); lateral longitudinal carina only present on metasomal tergite 1 and base of second metasomal tergite ( Fig. 4b ); pronotum with dorsal longitudinal depression ( Fig. 4c ) ................................................................................................. Chorinaeus Holmgren, 1858

– Mesopleuron without sulcus ( Fig. 4d ); lateral longitudinal carina often present on metasomal tergites 1–3 ( Fig. 4e ); pronotum without dorsal longitudinal depression ( Fig. 4f ) ...... Trieces Townes, 1946

5. Interantennal process of face connected dorso-posteriorly to a high lamella separating the antennal sockets, this lamella with a vertical groove in it, just below the median ocellus ( Fig. 5a ) .............. 6

– Interantennal process of face not produced dorsally into a lamellate structure separating the antennal sockets, but often present as a low lamella posterior to antennal bases ( Fig. 5b ) ............................ 7

6. First metasomal segment petiolate anteriorly, its spiracle near or posterior to centre ( Fig. 6a ); sternite 1 long, reaching more than half of length of tergite ( Fig. 6b ); mandible with teeth subequal ( Fig. 6c ) ............................................................................................... Colpotrochia Holmgren, 1856

– First metasomal segment weakly to quite strongly (and evenly) tapered anteriorly, its spiracle near its anterior ⅓ ( Fig. 6d ); first metasomal sternite short, at most reaching about ⅓ of length of tergite ( Fig. 6e ); mandible with lower tooth much shorter than upper tooth ( Fig. 6f ) ................................... ........................................................................................................................ Triclistus Förster, 1869

7. Pronotum with upper part inflated, the pronotal lobes appear as large triangular structures in dorsal view ( Fig. 7a ); upper tooth of mandible broadly lobate, lower tooth acute and turned upwards ( Fig. 7b ); interantennal process separated from upper face by a sharp transverse carina ( Fig. 7c ) .... .................................................................................................. Stethoncus Townes & Townes, 1959

– Pronotum with upper part not exceptionally inflated ( Fig. 7d ); upper tooth of mandible triangular and acutely pointed, the lower tooth generally small and always straight ( Fig. 7e ); interantennal process never separated from upper face by a carina ( Fig. 7f ) ......................................................... 8

8. Areolet present ( Fig. 8a ) ................................................................................................................... 9

– Areolet absent ( Fig. 8b ) ...................................................................................................................11

9. Occipital carina entirely absent ( Fig. 9a ) ............................................ Carria Schmiedeknecht, 1924

– Occipital carina present at least laterally ( Fig. 9b ) ......................................................................... 10

10. Notaulus present ( Fig. 10a ); first metasomal tergite distinctly narrowing basally ( Fig. 10b ) ............ .................................................................................................................... Sciron Fitton, 1984 (part)

– Notaulus absent ( Fig. 10c ); first metasomal tergite broad basally ( Fig. 10d ) ..................................... .................................................................................................................... Seticornuta Morely, 1913

11. Mid tibia with outer spur distinctly shorter than inner spur ( Fig. 11a ) ........................................... 12

– Mid tibia with outer spur as long as inner spur ( Fig. 11b ) .............................................................. 13

12. Occiput vertical ( Fig. 12a ); posterior transverse carina of mesosternum convexly bulging medioposteriorly ( Fig. 12b ); first metasomal tergite with distinct lateromedian carina often extending 0.8× of tergite ( Fig. 12c ) .......................................................................... Hypsicera Latreille, 1829 (part)

– Occiput rounded to steeply declivous ( Fig. 12d ); posterior transverse carina of mesosternum straight medio-posteriorly ( Fig. 12e ); first metasomal tergite without or with lateromedian carina, if present extending 0.5 × of tergite ( Fig. 12f ) ....................................................... Exochus Gravenhorst, 1829

13. Notaulus present ( Fig. 13a ); first metasomal tergite narrowing basally ( Fig. 13b ) ............................ .................................................................................................................... Sciron Fitton, 1984 (part)

– Notaulus absent ( Fig. 13c ); first metasomal tergite not narrowing basally ( Fig. 13d ) ................... 14

14. Propodeum without traces of carina ( Fig. 14a ); first metasomal tergite without carina ( Fig. 14b ); epicnemial carina largely incomplete or absent dorsolaterally ( Fig. 14c ) ................ Soliga gen. nov.

– Propodeum with distinct carina ( Fig. 14e ); first metasomal tergite with longitudinal carina ( Fig. 14f ); epicnemial carina complete ( Fig. 14d ) ........................................................................................... 15

15. Propodeum without anterior transverse carina ( Fig. 15a ); at least anterior ⅓ of second metasomal tergite with distinct longitudinal carina ( Fig. 15b ) .......................... Drepanoctonus Pfankuch, 1911

– Propodeum with anterior transverse carina ( Fig. 15c ); second metasomal tergite without distinct longitudinal carina ( Fig. 15d ) ......................................................................................................... 16

16. Occiput vertical ( Fig. 16a ); metasomal tergite 2 with wide laterotergite ( Fig. 16b ) .......................... .......................................................................................................... Hypsicera Latreille, 1829 (part)

– Occiput roundly sloping ( Fig. 16c ); metasomal tergite 2 with narrow laterotergite ( Fig. 16d ) ......... ............................................................................................... Macromalon Townes & Townes, 1959

Figures

Fig. 1. a. Metopius sp., head, anterior view. b. Triclistus sp., head, anterior view. Arrow in Fig. 1a points to raised carina delineating shield-shaped area (compared to lack of carina in Fig. 1b).

Fig. 2. a. Trieces irwini Ranjith & Priyadarsanan, 2022, metasoma, lateral view. b. Exochus sp., metasoma, lateral view. Arrow in Fig. 2a points to the lack of laterotergite on metasomal tergite 3–5 (compared to the presence of laterotergite on metasomal tergites 3–5 in Fig. 2b).

Fig. 3. a–c. Acerataspis sp.a. Fore wing.b. Metasoma, dorsal view.c. Mid leg.d. Hypsicera sp., fore wing.e. Trieces irwini Ranjith & Priyadarsanan, 2022, metasoma, dorsal view. f. Hypsicera sp., mid leg. Arrow in Fig. 3a points to the presence of fore wing areolet (compared to the absence of fore wing areolet in Fig. 3d. Arrow in Fig. 3b points to clavate metasoma (compared to parallel sided metasoma in Fig. 3e. Arrow in Fig. 3c points to single mid tibial spur (compared to the presence of two mid tibial spurs in Fig. 3f.

Fig. 4. a–c. Chorinaeus sp. a. Mesosoma, lateral view. b. Anterior metasomal tergites, lateral view. c. Mesosoma, dorsal view. d–f. Trieces isolatus Ranjith & Priyadarsanan, 2022. d. Mesosoma, lateral view. e. Anterior metasomal tergites, lateral view. f. Mesosoma, dorsal view. Arrow in Fig. 4a points to the presence of sulcus on mesopleuron (compared to the absence of sulcus on mesopleuron in Fig. 4d). Arrow in Fig. 4b points to metasomal tergites 2–3 without lateral carina (compared to metasomal tergites 1–3 with lateral carina in Fig. 4e). Arrow in Fig. 4c points to pronotum with dorsal transverse depression (compared to pronotum without dorsal transverse depression in Fig. 4f).

Fig. 5. a. Triclistus sp., head, dorsal view. b. Hypsicera sp., head, dorsal view. Arrow in Fig. 5a points to vertical lamellate structure on frons (compared to lack of lamella on frons in Fig. 5b).

Fig. 6. a–c. Colpotrochia sp. a. Metasomal tergite 1, dorsal view. b. Metasomal tergite 1, lateral view. c. Head, antero-ventral view. d–f. Triclistus sp. d. Metasomal tergite 1, dorsal view. e. Metasomal tergite 1, lateral view. f. Head, antero-ventral view.Arrow in Fig. 6a points to metasoma petiolate anteriorly (compared to broad metasoma anteriorly in Fig. 6d). Arrow in Fig. 6b points to metasomal tergite 1 with long sternite (compared to metasomal tergite with short sternite in Fig. 6e). Arrow in Fig. 6c points to mandible with subequal teeth (compared to the mandible with shorter lower tooth in Fig. 6f).

Fig. 7. a–c. Stethoncus sp. a. Mesosoma, dorsal view. b. Head, antero-ventral view. c. Head, antero-dorsal view. d–f. Exochus sp. d. Mesosoma, dorsal view. e. Head, antero-ventral view. f. Head, antero-dorsal view. Arrow in Fig. 7a points to inflated upper part of pronotum (compared to normally curved upper part of pronotum in Fig. 7d). Arrow in Fig. 7b points to lobe like upper tooth of mandible (compared to triangular, acutely pointed upper tooth of mandible in Fig. 7e). Arrow in Fig. 7c points to the presence of a sharp transverse carina separating interantennal processes and upper face (compared to the absence of transverse carina separating interantennal processes and upper face in Fig. 7f).

Fig. 8. a. Colpotrochia sp., fore wing. b. Trieces orientalis Ranjith & Priyadarsanan, 2022, fore wing. Arrow in Fig. 8a points to fore wing with areolet (compared to fore wing without areolet in Fig. 8b).

Fig. 9. a. Carria sp., head, dorsal view. b. Hypsicera sp., head, dorsal view.Arrow in Fig. 9a points to the absence of occipital carina (compared to the presence of occipital carina in Fig. 9b).

Fig. 10. a. Sciron fundator Fitton, 1984, mesosoma, dorsal view. b. Colpotrochia sp., metasomal tergite 1, dorsal view. c. Exochus sp., mesosoma, dorsal view. d. Trieces orientalis Ranjith & Priyadarsanan, 2022, metasomal tergite 1, dorsal view.Arrow in Fig. 10a points to the presence of notauli on mesoscutum (compared to the absence of notauli on mesoscutum in Fig. 10c). Arrow in Fig. 10b points to metasoma petiolate anteriorly (compared to broad metasoma anteriorly in Fig. 10d).

Fig. 11. a. Exochus sp., mid leg. b. Hypsicera, mid leg.Arrow in Fig. 11a points to mid tibia with shorter outer spur (compared to subequal midtibial spurs in Fig. 11b).

Fig. 12. a–c. Hypsicera sp. a. Head, lateral view. b. Mesosoma, ventral view. c. Metasomal tergite 1, dorsal view. d–f. Exochus sp. d. Head, lateral view. e. Mesosoma, ventral view. f. Metasomal tergite 1, dorsal view. Arrow in Fig. 12a points to vertical occiput (compared to rounded occiput in Fig. 12d). Arrow in Fig. 12b points to posterior transverse carina on mesosternum convex medio-posteriorly (compared to straight posterior transverse carina on mesosternum in Fig. 12e). Arrow in Fig. 12c points to the long lateromedial carina on first metasomal tergite (compared to the short lateromedial carina on first metasomal tergite in Fig. 12f).

Fig. 13. a. Carria sp., mesosoma, dorsal view. b. Colpotrochia sp., metasomal tergite 1, dorsal view. c. Trieces irwini Ranjith & Priyadarsanan, 2022, mesosoma, dorsal view.d. Trieces orientalis Ranjith & Priyadarsanan, 2022, metasomal tergite 1, dorsal view. Arrow in Fig. 13a points to the presence of notauli on mesoscutum (compared to the absence of notauli on mesoscutum in Fig. 13c). Arrow in Fig. 13b points to first metasomal tergite narrow basally (compared to first metasomal tergite broad basally in Fig. 13d).

Fig. 14. a–c. Soliga ecarinata gen. et sp. nov. a. Propodeum, dorsal view. b. Metasomal tergites 1–2, dorsal view. c. Mesosoma, lateral view. d–f. Triclistus sp. d. Propodeum, dorsal view. e. Metasomal tergites 1–2, dorsal view. f. Mesosoma, lateral view. Arrow in Fig. 14a points to the absence of propodeal carinae (compared to the presence of propodeal carinae in Fig. 14d). Arrow in Fig. 14b points to the absence of dorsal carinae on first metasomal tergite (compared to the presence of dorsal carinae on first metasomal tergite in Fig. 14e). Arrow in Fig. 14c points to the incomplete epicnemial carina (compared to the complete epicnemial carina in Fig. 14f).

Fig. 15. a. Carria sp., propodeum, dorsal view. b. Trieces isolatus Ranjith & Priyadarsanan, 2022, anterior metasomal tergites, dorsal view. c–d. Hypsicera sp. c. Propodeum, dorsal view. d. Anterior metasomal tergites, dorsal view. Arrow in Fig. 15a points to the absence of anterior transverse carina of propodeum (compared to the presence of anterior transverse carina of propodeum in Fig. 15c). Arrow in Fig. 15b points to the presence of midlongitudinal carina on second metasomal tergite (compared to the absence of midlongitudinal carina on second metasomal tergite in Fig. 15d).

Fig. 16. a–b. Hypsicera sp. a. Head, lateral view. b. Metasoma, ventral view. c–d. Macromalon sp. c. Head, lateral view. d. Metasoma, ventral view. Arrow in Fig. 16a points to vertical occiput (compared to rounded occiput in Fig. 16c). Arrow in Fig. 16b points to wide laterotergite on metasomal tergite 2 (compared to narrow laterotergite on metasomal tergite 2 in Fig. 16d).