The Ants of Africa SUBFAMILY MYRMICINAE - Genus Ocymyrmex
Contents - Myrmicinae - MYRMICINAE Introduction

Genus Ocymyrmex Emery (1886: 364)

Diagnostic Features

The original genus definition, Emery (1886) - is at . Arnold (1916: 194) gave a translation, genus notes and a key (for Southern Africa), these are at . Revised by Bolton (1981b) and further by Bolton & Marsh (1989). Bolton (1981b) can be seen at can be seen at - . and, the full text of the latter revision can be seen at - .

Note 2: Bolton & Marsh cite descriptions by "Prins & Roux (1989). Annals of the South African Museum (in press)". The full list of publications in the Annals can be seen at http://media1.mweb.co.za/iziko/education/pdfs/annals.pdf. The cited paper is not listed and, therefore, the validity of the names has to be questioned. These are cilliei, gariepensis and gordoni. Apart from characters given in the Bolton & Marsh key (1989: 1282) no descriptions exist. On the Antweb site at http://www.antweb.org//description.do?name=cilliei&genus=ocymyrmex&rank=species&project=worldants cilliei is listed as authored by Bolton & Marsh 1989 (provided by Barry Bolton, 2013); also for gariepensis at http://www.antweb.org/images.do?genus=ocymyrmex&name=gariepensis&rank=species&project=allantwebants and gordoni at http://www.antweb.org/description.do?genus=ocymyrmex&name=gordoni&rank=species&project=allantwebants

Key developed from Bolton & Marsh (1989) but without reliance on "invisible" characters, eg. palp formula and mandible teeth; distribution as per those authors.

Species-group	TL mm	Features	.
.	.	Southern African	Link
.	.	East African - Tanzania northwards - all with a low, narrow petiole node	.
weitzeckeri-group couplet 12	9.2-9.3 mm	Anterior margin of clypeus with a deep notch; dark dull red, postpetiole and gaster lighter yellowish	.
.	.		Somalia - robecchii
.	.	Anterior margin of clypeus impressed to sharply notched	next
weitzeckeri-group couplet 25	7.7-8.0 mm	Dorsum of head densely sculptured; alitrunk dark deep red, head visibly lighter, gaster blackish-brown to black	.
.	.		Kenya & Tanzania - phraxus
--		Dorsum of head near smooth giving a polished appearance	next
weitzeckeri-group couplet 28	7.4-7.8 mm	Pronotum profile markedly convex; shiny, glossy dull red, gaster darker blackish-brown to black	.
.	.		North-east Africa - nitidulus
weitzeckeri-group couplet 28	8.0-9.0 mm	Pronotum profile near flat; reddish ferruginous, gaster duller	.
.	.		South Sudan & Kenya - celer
.	.	Southern Africa - Zimbabwe southwards	.
barbiger-group couplet 20	??	Never described ?? but cf barbiger only males separable! Images of male on species page	South Africa & Namibia - cilliei
.	.	Anterior margin of clypeus with median semi-circular or V-shaped impression	Link
.	.	Anterior margin of clypeus at least weakly convex without a median semi-circular or V-shaped impression (part 2)	.
velox-group couplet 5	5.8 mm	Alitrunk jet black and shiny; head and gaster blackish-brown; anterior margin of clypeus usually with a blunt triangular prominence	.
.	,		Namibia (holotype, Walvis Bay) - turneri
.	.	Base of gaster strongly constricted to form a neck or collar	Link
.	.	Base of gaster not strongly constricted to form a neck or collar	.
velox-group couplet 8	8.4 mm	Relatively long scapes, SI 116; head very dark dull red, alitrunk glossy jet black, rest blackish-brown; basal half of gaster with numerous conspicuous hairs	.
.	.		Namibia (holotype only) - zekhem
--	--	Relatively short scapes, SI 105 or less	Next
velox-group couplet 9	9.7-10.2 mm	Uniform rich orange brown, gaster slightly paler; basal half of gaster with no more than a few inconspicuous hairs	Angola (single collection) - ankhu
velox-group couplet 9	10.0-10.7 mm	Alitrunk dull red to blackish red, both head and gaster lighter (gaster even to orange/yellow); basal half of gaster with no more than a few inconspicuous hairs	.
.	.		Namibia & Angola - velox
.	.	Base of gaster strongly constricted to form a neck or collar	.
laticeps-group couplet 7	7.2-7.6 mm	Overall red but alitrunk darker, base of gaster yellowish-orange; petiole node in profile with a short, narrowly rounded dorsum	.
.	.		Angola & Namibia - laticeps
laticeps-group couplet 7	9.7 mm	Alitrunk dull glossy red, head lighter with orange tint, gaster darker reddish-brown; petiole node in profile with an elongate, almost flat dorsum	.
.	.		Angola (holotype only) - cursor
.	.	Anterior margin of clypeus with a median semi-circular or V-shaped impression	.
.	.	Alitrunk profile bizarrely saddle-shaped, PF 5,3 (part 1)	.
cavatodorsatus-group couplet 3	4.5-5.0 mm	Head and appendages bright red, alitrunk and pedicel darker, gaster piceous	.
.	.		South Africa - cavatodorsatus
cavatodorsatus-group couplet 3	TL ??	Never fully described ??; median portion of clypeus with anterior section abruptly truncated cf cavatodorsatus but alitrunk profile not so bizarre - no images available	South Africa - gordoni
cavatodorsatus-group couplet 1	TL ca 4.5 mm	Never fully described ??; mandible usually (?) with only 4 teeth, rarely the third tooth with a minute denticle at its base; median portion of clypeus with anterior section abruptly truncated cf cavatodorsatus; cephalic sculpture unusual, consisting entirely of dense reticulate-punctuation	South Africa - gariepensis
.	.	Alitrunk profile no more than shallowly concave	.
.	.	TL < 6 mm	.
kahas-group couplet 19	5.2 mm	Entirely yellow - no images available	Namibia (single collection) - flavescens
kahas-group couplet 19	5.8 mm	Head glossy dull red, rest black with some reddish tints	Namibia (single collection) - afradu
barbiger-group couplet 21	5.8-6.0 mm	Brown, head and gaster with dull yellowish to dull orange tint, alitrunk dull reddish	Namibia & South Africa - dekerus
tachys-group part 4, couplet 15	5.4-5.5 mm	Head unicolorous dull orange-red, alitrunk red, gaster blackish (PF 2,3)	Namibia (single collection) - engytachys
tachys-group part 4, couplet 15	5.2-5.7 mm	Head dark reddish-brown (mandibles and anterior lighter), alitrunk black, gaster dark brown (PF 2,3)	Namibia (Skeleton Coast) - tachys
barbiger-group couplet 21	5.5 mm	Overall shining blackish brown, gaster darker, appendages red-brown	.
.	.		Namibia - robustior
.	.	TL > 6 mm to 9.0 mm	.
.	.	Alitrunk very densely hairy (part 7, couplets 31-35)	.
hirsutus-group couplet 33	6.9-7.8 mm	Unicolorous reddish; head with distinctive transverse vermiculate rugulae behind eyes	.
.	.		Botswana & South Africa - hirsutus
hirsutus-group couplet 34	7.9-8.3 mm	All but gaster very dull red (blackish to naked eye); gaster black	South Africa - ignotus
hirsutus-group couplet 32	6.2-6.9 mm	Orange to orange-red, gaster lighter than alitrunk	Namibia - micans
hirsutus-group couplet 35	7.9-8.6 mm	Head & alitrunk very dull dark red, gaster orange-red to yellowish	.
.	.		South Africa (poss Botswana, Namibia) - resekhes
hirsutus-group couplet 35	7.1-7.4 mm	Bright orange-yellow, gaster lighter and more yellow	.
.	.		Namibia, Botswana & South Africa - flaviventris
hirsutus-group couplet 31	6.7 mm	Uniform bright orange	.
.	.		Namibia (holotype only) - shushan
.	.	Alitrunk not densely hairy (part 6, couplets 23-30)	.
barbiger-group couplet 20	6.7-7.2 mm	Head and alitrunk orange or darker brick red, gaster darker to dull brown	Botswana & S. Africa - barbiger
weitzeckeri-group couplet 25	7.3-8.0 mm	Usually (in one colony only?) uniform orange-red, sometimes gaster lighter or darker	Zimbabwe & South Africa - foreli
weitzeckeri-group couplet 27	6.7-8.2 mm	Head and alitrunk unicolorous dull brick-red to lighter red, gaster blackish-brown to black	.
.	.		pan-southern Africa - fortior
kahas-group couplet-18	6.3-7.0 mm	Head dull orange-yellow, alitrunk darker reddish to reddish-brown, gaster more yellowish than head	,
.	.		Namibia (single collection) - kahas
weitzeckeri-group couplet 29	7.4-8.1 mm	Uniform dull red to reddish black; front of head with fine dense longitudinal costulae	Angola & Namibia - monardi
weitzeckeri-group couplet 30	6.3-7.3 mm	Dull reddish but with alitrunk contrasting blackish cf monardi	Namibia - okys
weitzeckeri-group couplet 24	7.6-8.8 mm	Tricoloured, head dull red, alitrunk darker reddish-black, gaster dull yellowish red	.
.	.		Botswana, South Africa & Zimbabwe - sobek
weitzeckeri-group couplet 30	6.7-7.8 mm	Overall dark red to blackish red, some even darker	.
.	.	Namibia specimen	South Africa & Lesotho - weitzeckeri
.	.	TL > 9.0 mm (part 3, couplets 11-13)	.
weitzeckeri-group couplet 11	11.6-12.6 unique mm	Very dark red to black (head lightest, gaster darkest); hairs on alitrunk dark reddish-brown to black (Namibia specimens appear near black)	.
.	.		pan-Southern Africa - picardi
.	.	Alitrunk densely hairy, the hairs white to silvery	.
hirsutus-group couplet 13	9.4-9.8 mm	Head dull red, alitrunk darker, gaster lighter; petiole node flattened with triangular sides	.
.	.		Botswana & South Africa - alacer
hirsutus-group couplet 13	9.3-10.1 mm	Very dull dark red, gaster black; petiole node from above with rounded sides	.
.	.		Botswana & South Africa - sphinx

MYRMICINAE Introduction

© 2007, 2011, 2013, 2015 - Brian Taylor CBiol FSB FRES 11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.

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