The Ants of Africa

The Ants of Africa
Genus Cerapachys

Genus Cerapachys F. Smith (1857a: 74), includes previous Phyracaces

Diagnostic Features - Antennae 11- (former Parasyscia) or 12-segmented, the apical funicular segment greatly swollen, forming a club. Genae longitudinally carinate, eyes present. Petiole a massive node, never marginate laterally. The gastral constriction may be extreme, so that in some species there is a petiole and a post-petiole. Middle and hind tibiae with two spurs, claws simple.

Smith's (1857a) genus definition is at . Emery (1902c) gave revisionary notes - these are at .

Described as uncommon by Bolton (1973a), who remarked that all known species raid the nests of other ants for food. They are generally specialist feeders on other species of ants, hence the armoured nature of the body (Hölldobler & Wilson, 1990, page 569). Brown (1975) observed Cerapachys species in Madagascar and India attacking nests of Pheidole species.

Brown (1975) separated the African species into the following groups: the wroughtoni group, from S. Africa, of small species, with 12-segmented antennae, the eyes minute or absent, and promesonotal suture well developed; the cribrinodis group (centurio, cribrinodis, sudanensis and villiersi from West Africa and the Congo Basin); the mayri group (coxalis, foreli, and nkomoensis from West Africa and the Congo Basin); and indeterminate (decorsei and similis).

Arnold (1926) gave a key to South African species, this is at . Brown's (1975) key is at .

Key to workers of species known from Africa (after Brown, 1975).

¤	Male only known	Chad - decorsei
¤	Male only known	Ivory Coast - similis
¤	Male only known	Kenya - niger
1	Antennae with 11 segments	2
--	Antennae with 12 segments	4
2	TL 2.8-3.8; eyes quite large; sculpturation only of scattered hair pits, reduced to tiny on gaster; petiole with concave anterior face; shiny, colour dark brown	.
.		Pan-African - sudanensis
--	Eyes reduced, with less than 15 facets	3
3	TL 3.5 mm; smooth and shiny with almost whole of head and alitrunk with large pits from which a yellowish hair arises, finer pits on the posterior four segments of gaster; antennae and legs with very fine decumbent pubescence; ferruginous yellow with apex of gaster browner [nothing given by Brown, 1975]	Syria {extra-limital] piochardi
--	TL 3.3-3.4 mm; shiny, sparsely punctate; piceous, appendages medium brown	.
.		West Africa & Congo Basin - nitidulus
4	Petiole node with sharp dorsolateral angles	5
--	Petiole node without dorsolateral margins, dorsum smoothly rounding into sides	11
5	Petiole node from above with 2 broadly rounded nodes, separated by a deep concavity; TL 3.5 mm; piceous	South Africa - braunsi
--	Petiole node with angulate or dentate posterolateral angles	6
6	Alitrunk coarsely longitudinally costulate for entire length, colour black	7
--	Alitrunk dorsum smooth or punctate; longitudinal costulae, if any, confined to anterior and posterior extremities	8
7	Head smooth; TL 3.5-3.7 mm; dark brown to black	.
.		West Africa & Congo Basin - foreli
--	Head with longitudinal costulae, at least on occiput	Guinea - occipitalis
8	Petiole node with fine sculpture whereas alitrunk smooth; petiole also with much denser pubescence. Propodeal declivity smooth	9
--	Alitrunk, petiole, postpetiole and gaster shining, with small but very distinct round punctures	10
9	Eye small < length of apical segment of funiculus; TL 3.4 mm (Kenya) 4.2-4.5 mm (South Africa); piceous	Kenya (montane) & South Africa - vespula
--	Eye larger > length of apical segment of funiculus; TL 2.8 mm (Nigeria slightly larger); black	.
.		Zimbabwe & Nigeria - coxalis
10	TL 4.2-4.6; scape reaches posterior third of head; shiny, black	Congo Basin - nkomoensis
--	TL 2.8 mm; petiole without postero-dorsal teeth; colour ferruginous except lower postpetiole and gaster which are black	Kenya - braytoni
	Petiole node without dorsolateral margins, dorsum smoothly rounding into sides	--
11	Eyes minute or absent	12
--	Eye quite distinct to moderate in size	13
12	TL 2.0-2.3 mm; with distinct promesonotal suture; eyes absent; smooth (other than punctures) and shiny, yellow brown	southern Africa - wroughtoni
--	TL 4.3 mm; promesonotum without any sign of suture; eye very small but distinct; dark ferruginous	.
.		East Africa - kenyensis
13	Petiole node slightly but distinctly longer than broad; TL 5.6-5.7 mm	Central Africa - centurio
--	Petiole node broader than long	14
14	Petiole node with distinct median point in posterodorsal margin	15
--	Petiole node with straight or slightly concave posterodorsal margin	16
15	TL 4.0 mm; petiole with median point in posterior margin, dorsum in profile convex; ventral lobe of petiole with distinctive angles at anterior and posterior; castaneous	South Africa - peringueyi
--	TL 2.4-3.0 mm; black; petiole with flat dorsum in profile	.
..		East & southern Africa - afer
--	TL 3.5 mm; petiole assumed similar; paler and more reddish than peringueyi	South Africa - arnoldi
16	TL 4.3; mm; dorsum of head, alitrunk and pedicel very finely roughened and opaque; first gastral segment with very fine dense puncturation on shiny surface; black	South Africa - sylvicola
--	Dorsum of head mostly smooth or nearly so	17
17	TL 5.0 mm; petiole and postpetiole with coarse, contiguous and confluent punctures; dark reddish-brown	east and south central Africa - lamborni
--	Petiole and postpetiole otherwise sculptured	18
18	TL 4.3 mm; petiole from above near square; black	Zimbabwe - validus
--	Petiole from above with posterior wider than anterior	19
19	TL 2.7 mm; pale burnt sienna brown	.
.		South Africa & Tanzania - faurei
--	Darker reddish-brown to black	20
20	TL 2.6 mm; head, alitrunk and petiole with large deep puncturations; uniform brown-red, shiny, appendages yellow;	Guinea - villiersi
--	Head, alitrunk and petiole with smaller, shallower puncturations	21
21	TL 3.7-4.0 mm; postpetiole with deep ventral process; sculpturation of small hair pits; blackish-brown, apices of body and appendages brownish-red	West Africa & Congo Basin - cribrinodis
--	TL 4.0 mm; pronotum wider; pedicel more weakly sculptured but alitrunk and head more densely punctured; antennae and mandibles entirely reddish	South Africa - natalensis

Cerapachys new species.

Found in Ghana, by Belshaw & Bolton (1994b) in leaf litter samples from the semi-deciduous forest zone, with single workers from primary forest at Esukawkaw Forest Reserve, and secondary forest at Atewa Forest reserve and CRIG.

Cerapachys species F (as Phyracaces species F)

From Ghana in a cocoa canopy sample, by Room (1971).

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