Key to the species of Indian subcontinent Alysson (modified from Tsuneki, 1968)
1. Mesosoma with ferruginous red markings.................................................................. 2
- Mesosoma (except tegulae) entirely black (sometimes with creamy white spots at pronotum and scutellum).............. 3
2. Propleuron striate in middle; propodeal enclosure with two central carinae united at apex; setae on frons and vertex silvery. ♀. India: Himachal Pradesh ................................................. Alysson erythrothorax Cameron, 1902
- Propleuron simply aciculate at base, not striate; propodeal enclosure with two central carinae not united at apex; setae on frons and vertex black. ♀, ♂. Sri Lanka ............................................. Alysson ruficollis Cameron, 1902
3. Propodeal enclosure apically triangular.................................................................... 4
- Propodeal enclosure apically rounded..................................................................... 6
4. First metasomal segment completely and second metasomal segment mostly yellowish red (except black apex and typical creamy yellow lateral spots on second tergite). ♀. India: Himachal Pradesh .............. Alysson himachalensis sp. nov .
- Metasoma entirely black................................................................................ 5
5. Propodeal enclosure only longitudinally carinated; outer area of dorsal side of propodeum with only few radiating striae from outer margins of propodeal enclosure; posterior side of propodeum on each side of the median carina smooth; no creamy white spots on pronotum, scutellum and basal fourth of hind tibia; OOL 3–4 × POL in female; forewing with two infumated bands in female; pygidial setae silvery. ♀. India: West Bengal .................................. Alysson bengalensis sp. nov .
- Propodeal enclosure rugoso-reticulated; outer area of dorsal side of propodeum with numerous areolets; posterior side of propodeum areolated; pair of creamy white spots present on pronotum, scutellum and basal fourth of hind tibia; OOL 1.55 × POL in female; forewing with a single infumated band in female; pygidial setae brownish. ♀, ♂. Sri Lanka; India: Tamil Nadu ........................................................................ Alysson triangularis Krombein, 1985
6. Posterior side of propodeum areolated; clypeus with extreme apex brownish black; forewing with a single infumated band (scutellum with two spots; mid and hind legs blackish and from coxae apically subannulately maculated with yellow). ‘ ♀ ’ = ♂. India: Maharashtra, West Bengal .............................................. Alysson annulipes Cameron, 1897
- Posterior side of propodeum on each side of the median carina smooth; clypeus with extreme apex not brownish black; forewing with two infumated bands (mid and hind legs black, with tarsi dark brown). ♀. India: Himachal Pradesh .................................................................................. Alysson testaceitarsis Cameron, 1902