Gastralysia Fischer, 1967

van Achterberg, Cornelis & Tan, Jiang-Li, 2018, Revision of the enigmatic genus Gastralysia Fischer (Hymenoptera, Braconidae, Alysiinae), Journal of Hymenoptera Research 65, pp. 149-156 : 149

Gastralysia Fischer, 1967

Figures 1 , 2-10 , 11-16

Gastralysia Fischer, 1967: 110, 134. Type species (by monotypy): Gastralysia garambana Fischer, 1967 [lost?].

Diagnosis.

Antenna with 39-41 segments and third segment (including annellus) 0.9 × as long as fourth segment; epistomal sulcus crenulate (Fig. 7 ); median groove of mesoscutum complete and similarly crenulate as complete notauli (Fig. 5 ); posterior half of precoxal sulcus vertical, runs to mesosternum and nearly connecting to lamelliform postpectal carina; pleural sulcus wider than precoxal sulcus and coarsely crenulate (Fig. 4 ); mesosternal sulcus medium-sized and crenulate; propodeum very short, in dorsal view slightly longer than metanotum (Fig. 5 ) and with curved transverse lamelliform carina; antero-dorsally propodeum with a parallel-sided lateral lamellae (spine-shaped in lateral view) as long as posterior metanotal lamella (♂) or distinctly longer (♀); vein CU 1b of fore wing longer than vein cu-a, only pigmented, interstitial with vein m-cu and reclivous; vein 2-SR of fore wing longer than vein 3-SR; first subdiscal cell of fore wing ventrally and posteriorly without sclerotized veins; hind wing reduced (Fig. 3 ) and vein cu-a absent; tarsal claws normal (Fig. 10 ); first metasomal tergite 0.5-0.6 × as long as its apical width, movably connected to second tergite (Fig. 11 ), with its dorsal carinae flattened and posteriorly united in a wide median lamella (Fig. 5 ); dorsope absent; second and third metasomal tergites form a strongly convex carapace, closed apically, with serrate ventral margin posteriorly and covering following segments; hypopygium long (Fig. 11 ); ovipositor short and its sheath only apically setose (Fig. 11 ).

Biology.

Unknown.

Distribution.

Afrotropical (Zaire, Ivory Coast, Tanzania ). One species.

Notes.

Fischer (1976) placed Gastralysia in his "Gruppe F" because of the complete wing venation, third antennal segment as long as fourth segment or longer, vein 2-SR not shorter than vein 3-SR of fore wing and second metasomal tergite sculptured. Gastralysia does not fit in with the other genera of this group (e.g., Trachyusa Ruthe, 1854 and Bobekia Niezabitowski, 1910) because of having the third antennal segment slightly shorter than the fourth segment (Fig. 12 ), an entirely differently shaped hind wing, propodeum and first tergite, different venation of the fore wing, etc. It fits somewhat better in his "Gruppe C" because of the shortened third antennal segment and in this group it has some superficial resemblance to the Oriental and East Palaearctic genus Hylcalosia Fischer, 1967. The latter has also a coarsely sculptured (but less convex) carapace formed by the second and third metasomal tergites (e.g., van Achterberg 1983, Belokobylskij 2015, Zhu et al. 2017) and the third antennal segment is more or less widened in lateral view. However, it differs in the shape of the mandible, clypeus, head, propodeum and ovipositor as well as in several details of the venation. Actually, Gastralysia occupies a very isolated position within the Alysiini and, therefore, we propose a new subtribus for this genus, Gastralysiina subtrib. n. The new subtribus is monobasic (including only Gastralysia Fischer) and differs from all other Alysiini by the apically closed and strongly convex carapace, the long unsclerotised and reclivous vein CU 1b of the fore wing, the wide median lamella of the first tergite united to a flattened ring of carinae submedially and the enlarged hypopygium.

Figures

Figure 1. Gastralysia garambana Fischer, ♀, Ivory Coast, habitus, lateral aspect.

Figures 2 - 10. Gastralysia garambana Fischer, ♀, Ivory Coast. 2 fore wing 3 hind wing 4 mesosoma lateral aspect 5 mesosoma dorsal aspect 6 first-third metasomal tergites dorsal aspect 7 head anterior aspect 8 head dorsal aspect 9 head lateral aspect 10 hind leg lateral.

Figures 11 - 16. Gastralysia garambana Fischer, ♀, Ivory Coast. 11 metasoma lateral aspect 12 basal segments of antenna 13 apical segments of antenna 14 antenna 15 mandible, full on first tooth lateral aspect 16 metasoma posterior view.