The Ants of Africa
Genus Tetramorium species-groups -

Part 1
Tetramorium Introduction

DIV1
Species groups
Part 1 - former Triglyphothrix

Some or all erect hairs of dorsum of head or body branched (bifid, trifid or quadrifid)
Triglyphothrix
Otherwise next stage of key next primary division
grebennikovi-group Small species, TL ca 2.0, without elongate simple hairs in a row on the anterior edges of the scapes or along the upper borders of thescrobes
Otherwise next stage of key next species-group
-- Head rectangular with width much less than length, CI 84; very strongly reticulo-rugose; mandibles smooth; clypeus without a raised tranverse carina; gaster with distinctive minute hair pits; TL ca 2.0 mm; dark brown, appendages golden-brown
{short description of image}
Tetramorium grebennikovi Tanzania
ericae-group Very small to minute species (TL < 2.4 mm), all with elongate simple hairs in a row on the anterior edges of the scapes and along the upper borders of the scrobes
Otherwise next stage of key next species-group
11-segmented antennae, palp formula 3,3
02* Much reduced sculpture; TL 1.8 mm; black, tibiae yellowish-white
{Tetramorium antrema}
Tetramorium antrema Cameroun & Congo
03* Distinctly reticulo-rugose; clypeus with a raised tranverse carina; eyes with a distinctive anterior point; TL 1.6-1.9 mm; yellow-brown
{Tetramorium muscorum}
Tetramorium muscorum Pan-African forests
03* Distinctly reticulo-rugose; clypeus without a raised transverse carina; TL 1.9-2.1 mm; head with long simple hairs; gaster and postpetiole smooth & shining; black, appendages yellow-brown Tetramorium crypticum Ghana
12-segmented antennae, palp formula normal 4,3
12* Strongly bicoloured, head and gaster black, rest clear yellow; TL 1.7-1.9 mm Tetramorium distinctum Ghana
- Unicolourous or at most with darker gaster
10* Dorsal surfaces of head and alitrunk unsculptured other than median carina on head; TL 2.3-2.4 mm; dark blackish-brown
{Tetramorium menkaura}
Tetramorium menkaura Ghana
13* Clypeus with a raised tranverse carina; TL 1.7-2.0 mm; dark brown, appendages lighter
{Tetramorium minimum}
. .
. {Tetramorium minimum} Tetramorium minimum West African & Congo Basin forests
15* (as paupera) Clypeus without a raised tranverse carina; TL 1.8-2.0 mm; yellow to mid-brown, gaster may be darker Tetramorium ericae Zimbabwe
osiris-group Larger and gaster with dense mat of quadrifid hairs; both upper scrobe margins and leading edges of scapes with a row of elongate simple hairs
Otherwise next stage of key next species group
14* Anterior of first gastral tergite with coarse punctate sculpture; TL 3.4 mm; uniform dark brown
{Tetramorium yarthiellum}
Tetramorium yarthiellum Zambia
16* First gastral tergite smooth; distinctive narrow down-curved propodeal spines; TL 2.8-2.9 mm; brown with much darker gaster
{Tetramorium osiris}
Tetramorium osiris Ghana
23* With very strong antennal scrobes and few erect long hairs; TL 3.4 mm; light yellowish-brown
{Tetramorium reptana}
Tetramorium reptana Uganda
rothschildi-group Large species, lacking antennal scrobes; anterior clypeal margin with deep median impression
Otherwise next stage of key next species group
06* TL 3.8-4.7 mm; red-brown
{Tetramorium rothschildi}
Tetramorium rothschildi Dry southern Sahel
Ethiopia, Kenya & Ghana
inezulae-group Without long simple hairs on scapes but with a row on the upper scrobe margin; most with compressed petiole node
Otherwise next stage of key next species group
07* Uniquely, without branched hairs; alitrunk dorsum densely reticulo-punctate; TL 2.4-2.9 mm; yellow-brown
{Tetramorium arnoldi}
Tetramorium arnoldi Zimbabwe
10* Without propodeal spines; TL 2.4 mm; dorsum of head and alitrunk rugulose; clear ferruginous brown
{Tetramorium imbelle}
Tetramorium imbelle Ethiopia
TL max 3.3 mm
22* Yellow or light yellow-brown; TL 1.8-2.1 mm;CI 89-95; dorsal alitrunk finely rugo-reticulate;
{Tetramorium gestroi}
Tetramorium gestroi Southern area of wet forests
Angola, Gabon and Uganda
Dark brown to black
22* TL 2.2-2.5 mm; CI 90-96; base of gaster smooth; eyes small; antennal scrobe with strong longitudinal median carina; dorsal alitrunk longitudinally rugose; black to blackish-brown
{Tetramorium furtivum}
Tetramorium furtivum Wet western forests
Angola to Ghana
20* Base of gaster densely punctate; antennal scrobe with weak median longitudinal carina, lower portion of scrobe sculptured above the eye; mandibles striate; TL 2.2-2.3 mm, CI 86-92; dark brown Tetramorium trimeni South Africa
20* Base of gaster densely punctate; antennal scrobe with strong longitudinal median carina; TL 2.5-3.3 mm, CI 90-97; medium to dark brown
{Tetramorium inezulae}
Tetramorium inezulae East Africa
includes eastern Zaïre
(17*) Worker not known - may be sexuals of inezulae Tetramorium desertorum Botswana
TL at least 3.4 mm
17* Eyes minute, diameter less than width of scape; TL 3.4-3.7 mm; mandibles striate; sculpturation rugulose and weakly longitudinal; yellow to yellow-brown
{Tetramorium microps}
Tetramorium microps Southern Africa
19* First gastral tergite with only simple hairs; TL 3.6-3.8 mm; pale yellow-brown
{Tetramorium talpa}
Tetramorium talpa Eastern Zaïre
21* Large species TL 3.6-3.8 mm; brown, gaster usually darker
{Tetramorium tenebrosa}
Tetramorium tenebrosum Mozambique & Kenya
gabonense-group Stocky with overall covering of branched trifid or quadrifid hairs
- Without antennal scrobes
05* Propodeum unarmed; TL 3.5 mm; brown
{Tetramorium agnum}
Tetramorium agnum Zaïre
06* Propodeum with short teeth; TL 2.7-3.6 mm; dark brown
{Tetramorium eminii}
. .
. {Tetramorium eminii} Tetramorium eminii Pan-African
- With well developed antennal scrobes
23* Propodeum unarmed; minute TL 2.3 mm; uniform light brown
{Tetramorium dedefra}
Tetramorium dedefra Angola & Uganda
- Propodeum with spines or acute teeth
24* Bicoloured, head bright golden-yellow, rest blackish-brown; TL 2.7 mm
{Tetramorium pulcherrimum}
Tetramorium pulcherrimum Forests of western Uganda & eastern Zaïre
- Unicolourous; head and/or gaster may be darker than alitrunk
TL < 3.0 mm
30* TL 2.4 mm; mandibles smooth & shining; mid-brown, legs lighter Tetramorium thoth South Africa
26* TL 2.3-2.8 mm; branched hairs on dorsal surfaces all appressed, lying flat; uniform dark brown; Tetramorium sericeum Zimbabwe
TL > 3.0 mm
With long propodeal spines
27* Petiole from above strongly crescent shaped; TL 4.0 mm; dark brown
{Tetramorium monardi}
Tetramorium monardi Angola
32* Clypeus with weak or incomplete median carina; postpetiole with little or no sculpturation; TL 3.8-4.6 mm
{Tetramorium gabonense}
Tetramorium gabonense Wet forests of Cameroun east to Central Africa
32* Clypeus with strong median carina; postpetiole strongly sculptured; TL 3.0-3.6 mm; uniform mid-brown
{Tetramorium constanciae}
Tetramorium constanciae East Africa
With reduced propodeal spines
29* Head convex in front view; lower portion of antennal scrobe densely reticulo-rugose; TL 3.4 mm
{Tetramorium baufra}
Tetramorium baufra Zimbabwe
31* Petiole node from above with convex anterior face; TL 3.2-3.9 mm; variable brown
{Tetramorium brevispinosum}
. .
. {Tetramorium brevispinosum} Tetramorium brevispinosum Wet forests of West & Central Africa
31*
(as silvestrii)
Petiole node from above with flat anterior face; smaller TL 3.1 mm
{Tetramorium surrogatum}
Tetramorium surrogatum Ethiopia
return to start of key stage
Contents
© 2007, 2008 - Brian Taylor CBiol FIBiol FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.

href="tetramorium_groups_1.htm"