Key to the species of Scolomus

1 Mandible stout with small acuminate teeth of the same length. Labrum apex always visible, even with mandibles closed. Wings with a pentagonal areolet, veins 2RS and rs-m touching 3RSa separately. Subtegular ridge produced as a sharp, curved spine. Deep groove between the propodeum and metanotum................................................... 2

- Mandible slender with upper tooth distinctly longer than the lower tooth. Labrum more or less concealed when mandibles closed (Figs 1, 3, 5). Areolet slightly petiolate, rhombic, with 2RS vein joining rs-m shortly before touching 3RSa (Figs 2, 4, 6). Subtegular ridge not produced as a sharp spine. Shallow groove between the propodeum and metanotum................ 3

2(1) Propodeum without areola, posterior transverse carina incomplete. Lateral longitudinal carina sharper and more distinct near propodeal spiracle............................................................. S. magellanicus Walkley 1962

- Propodeum with areola delimited by the lateromedian longitudinal, anterior and posterior transverse carinae. Lateral longitudinal carina faint, indistinct near propodeal spiracle.................................. S. viridis Townes & Townes 1950

3(1) Propodeum with no trace of lateromedian longitudinal carina. Head and mesoscutum with reddish brown marks, fore leg orange brown. Central America............................................ S. talamanca (Gauld & Sithole 2002)

- Propodeum with lateromedian longitudinal carina discernible. Head and mesoscutum without reddish brown marks, fore leg brown or green...................................................................................... 4

4(3) Body mostly blackish, without extensive green areas. Female supra-clypeal area with simple, uniformly distributed setae. Propodeum with lateral longitudinal carina incomplete. Holarctic........................... S. borealis (Townes 1971)

- Body with extensive green areas. Female supra-clypeal area with clusters of seemingly bifurcate setae. Propodeum with lateral longitudinal carina complete. Chile...................................................................... 5

5(4) Clypeus width 3.00× its height (Fig. 1). Distance between eye and lateral ocellus 1.50× diameter of lateral ocellus. Areolet 0.80× as wide as long. Hypopygium 1.55× as long as wide, in lateral view. Ovipositor 12.50× as long as basal width. Head, mesoscutum, postscutellum and pronotum entirely brownish yellow............................. S. clypeatus sp. nov.

- Clypeus width 1.55×–2.30× its height (Fig. 3, 5). Distance between eye and lateral ocellus 0.90×–1.00× diameter of lateral ocellus. Areolet 1.00× as wide as long. Hypopygium 1.90× as long as wide, in lateral view. Ovipositor 5.30× as long as basal width. Head and pronotum greenish, mesoscutum yellow with dark brown spots on lateral lobes and around scutellum......................................................................................... S. maculatus sp. nov.