The Ants of Africa SUBFAMILY DORYLINAE - Subgenus Rhogmus
Genus Dorylus and Key

Subgenus Rhogmus Shuckard (1840c: 323)

Diagnostic Features - Antennae 11-jointed; worker major 8 mm long; subapical tooth of mandibles double or truncate; impressed area of pygidium without sharp margins.

Shuckard's (1840c) genus definition, based on the male of "Rhogmus fimbriatus", is at . Reduced to subgenus of Dorylus by Emery (1895j: 702).

Separation of known major workers 1 Major worker with 11-segmented antennae; TL ca 7.2-7.5 mm fimbriatus -- Major worker with 10-segmented antennae 2 2 TL 3.8-6.9 mm; promesonotum smooth; generally more yellow fuscipennis -- TL (2 specimens only) 4 mm & 5.5 mm; head rectangular longer than wide, with shorter occipital notch; promesonotum with distinct suture; reddish yellow-brown termitarius

Queens The queen only is known for - Ivory Coast - ocellatus

Males Santschi (1919b) separated the males as follows -

1 Pygidium deeply impressed (scalloped) - apex of gaster swollen and much wider than first to third segments 2 -- Pygidium scarcely or not scalloped 5 2 Wings blackish; TL 28-32 mm, HW 4.8; alitrunk width 5.5-5.7 mm; head higher than fimbriatus with less convex eyes; petiole two-thirds wider than long; reddish-fawn with gaster brownish at posterior edge of first segment (postpetiole), gastral spiracles with a distinct border that is of a darker brown like the tibiae, extremities of the tarsi and the edge of the mandibles; head blackish; a reddish pilosity, long and silky, covers the alitrunk, posterior edge of the petiole, the last segments of the gaster, the external borders of the femora, the underside and edge of the clypeus; face, gaster and pygidium with dense golden pubescence Ivory Coast - male only known - leo -- Wings yellowish 3 3 Pygidium pubescent, except for a median line 4 -- Pygidium shining with several clear hairs; slightly more robust, anterior wing 23 mm Kenya - fimbriatus ssp laevipodex 4 Thorax length 6 mm; TL ca 37 mm, wing-spread 46 mm Pan-African - fimbriatus -- Thorax length 5.2 mm Congo - fimbriatus ssp crampeli 5 Apical third of mandibles wide, gaster cylindrical, underneath of hypopygium shiny, not velvety 6 -- Apical third of mandibles tapering, gaster club-shaped, underneath of hypopygium matt and velvety 7 6 Mandibles large, stipes rounded; TL 28-33 mm (head + alitrunk + petiole 12-13.5 mm); dark brownish-yellow, head brown; dark red-brown mandibles, antennae, petiole and genitalia; wings dark brown with black veins West Africa & Congo Basin - male only known - savagei -- Stipes more acuminate savagei ssp mucronatus 7 TL 28-30 mm, alitrunk 9.5 X 5.3-6 mm, forwing 20-21 mm; alitrunk clear red, gaster brownish West Africa & Congo Basin - fuscipennis -- Colour otherwise 8 8 Entirely brown fuscipennis ssp lugubris -- clear red with gaster segments edged with brown fuscipennis ss marginiventris

Genus Dorylus and Key

© 2007 - Brian Taylor CBiol FIBiol FRES 11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.

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