The Ants of Africa
Genus Tetramorium species-groups - Part 6
Tetramorium Introduction


Species groups
Part 6 - former Tetramorium (Tetramorium)
species with short antennal scapes, larger eyes and nodiform petioles

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(SUB4) Frontal carinae long, extending beyond posterior margin of eyes, often to occipital margin
SUB5 Anterior clypeal margin with a distinct median notch or impression
Otherwise next stage of key sub-section

Note the anterior notch is much reduced in some T. lucayanum next stage of key but that (and the related versiculum) has the petiole seen from above as distinctively trapezoidal widening from front to back

Occipitum rugo-reticulate
Otherwise next stage of key next species group
bicarinatum-group -
88 Sculptured mandibles but only very finely striate; TL 3.4-4.5 mm; head and alitrunk light yellow-brown to bright orange-yellow, gaster always much darker to blackish-brown
{Tetramorium bicarinatum}
. .
. {short description of image} Tetramorium bicarinatum Exotic complex
pan-tropical tramp
found once in South Africa
- Mandibles smooth with scattered small pits
African complex-1 Large size HW > 0.80, petiole bluntly nodiform
70 Propodeum with minute teeth; TL 4.5-5.0 mm; uniform dark brown
{Tetramorium emeryi}
. .
. {Tetramorium emeryi} Tetramorium emeryi South Africa
72 Long propodeal spines; TL 4.2-5.0 mm; uniform dark brown
{Tetramorium erectum}
. .
. {Tetramorium erectum} Tetramorium erectum South Africa
African complex-2 Fairly large HW 0.70-0.80; petiole node roughly rectangular in profile
68 Bicoloured, orange-brown, gaster much darker; TL 4.1-5.1 mm
{Tetramorium cristatum pedicel}{Tetramorium cristatum}
. .
. Tetramorium cristatum Tetramorium cristatum sub-sahelian forests
71 Uniform dark brown; TL 4.1-4.9 mm
{Tetramorium gazense}
. .
. {Tetramorium gazense} Tetramorium gazense eastern Congo Basin into Tanzania
67 Uniform bright orange-brown; TL 3.5-5.0 mm
{Tetramorium notiale}
. .
. {Tetramorium notiale} Tetramorium notiale eastern southern Africa
African complex-3 Smaller HW < 0.70; petiole node long & low
67 Uniform pale yellow to light brownish yellow; TL 2.9-3.6 mm
Tetramorium phasias
Tetramorium phasias eastern southern Africa
68 Head & alitrunk orange, gaster near black; TL 2.9-3.5 mm
{Tetramorium peutli}
. .
. {Tetramorium peutli} Tetramorium peutli western forests
Ivory Coast round to Angola
69 Uniform blackish-brown or black; pedicel smooth; TL 3.2-4.0 mm
{Tetramorium pullulum}
Tetramorium pullulum Congo Basin
72 Black, appendages dark brown; pedicel sculptured, coarsely rugose; TL 3.1-3.6 mm
{Tetramorium amentete}
. .
, {Tetramorium amentete} Tetramorium amentete Ivory Coast & Ghana
Occipitum with little sculpturation
Propodeum with a pair of small teeth or denticles and rugo-reticulate
Otherwise next stage of key next species group
39 & 160 First gastral tergite reticulate-punctate or shagreened, as is dorsal alitrunk TL 3.6-4.4 mm; uniform medium to dark brown
{Tetrmorium jauresi}

. {Tetrmorium jauresi} Tetramorium jauresi eastern southern Africa
39 First gastral tergite completely smooth, as is dorsal alitrunk; TL 3.4-4.7 mm; uniform mid-brown
{Tetramorium qualarum}
. .
{Tetramorium qualarum}
Tetramorium qualarum Ghana
Propodeum with a pair of spines
Dorsum of petiole and postpetiole unsculptured or only slightly marked
Otherwise next stage of key next species group
camerunense-group camerunense-complex -
- Entirely yellow or yellowish-brown
129 Mandibles striate; TL 2.8-3.1 mm
{Tetramorium luteipes}
. .
. {Tetramorium luteipes} Tetramorium luteipes Congo
- Mandibles smooth with scattered pits
76 Alitrunk dorsum irregularly rugulose; petiole node with tranverse crest at anterior of dorsum; TL 2.4-2.6 mm
{Tetramorium gegaimi}
. .
. {Tetramorium gegaimi} Tetramorium gegaimi Zare
- Alitrunk dorsum longitudinally rugulose; petiole node without tranverse crest at anterior of dorsum
77 Dorsal alitrunk with elongate, fine, acute erect hairs; distinctive colouration, the head and alitrunk being glossy dull yellow and the gaster brown; TL 2.6-2.9 mm
Tetramorium browni
Tetramorium browni Ghana
77 Dorsal alitrunk with short, quite stout, blunt erect hairs; TL 3.1 mm
{Tetramorium miserabile}
Tetramorium miserabile Kenya
- Dark brown or black
78 Head with sharply developed, well defined rugulae, spaces between shiny; TL 2.7-3.1 mm
Tetramorium camerunense
Tetramorium camerunense Ghana, Cameroun & CAR
- Head and dorsal alitrunk with highly reduced sculpturation
NA Larger species TL 3.5 mm HL 0.70-0.77 HW 0.63-0.71 CI 90-92 SL 0.53-0.58 SI 82-84; petiole node broader than long in dorsal view; pedicel segments unsculptured
{Tetramorium boehmei}
Tetramorium boehmei Kenya
- Head with blunt, poorly defined rugulae, spaces between densely punctate or granular
78 Larger species TL 3.5 mm HL 0.85 HW 0.78 CI 92 SL 0.58 SI 74; petiole node broader than long in dorsal view; massively developed petiole and pedicel segments moderately sculptured
{Tetramorium ubangense}
. .
. {Tetramorium ubangense} Tetramorium ubangense Zare
- Smaller, TL max 3.0 mm, HW max 0.66
80 Head long & narrow CI 85; scapes relatively long SI 84; Tetramorium hapale Ivory Coast
80 Head broader CI 88-92; scapes shorter SI 78-80
{Tetramorium ictidum}
Tetramorium ictidum Cameroun
Dorsum of petiole and/or postpetiole distinctly sculptured
camerunense-group lucayanum-complex Node of petiole longer than broad in dorsal view
88 With suberect fairly long pubescence on hind tibiae; TL 3.6 mm; uniform dark brown
Tetramorium tychadion
Tetramorium tychadion Tanzania
- With decumbent to appressed short pubescence on hind tibiae
81 & 134 Dorsum of head with fine regular longitudinal rugulae, spaces between polished; postpetiole hardly sculptured; TL 2.8-3.3 mm; uniform mid-brown to black
{Tetramorium lucayanum}
. .
. apparent type form (Wheeler, 1905b) - head quadrangular, anterior border of clypeus transverse, erect hairs long and sparse on the body
Tetramorium lucayanum
. .
. form as illustrated by Bolton (1979) - head with more convex sides, smaller eyes and more abundant erect hairs
{Tetramorium lucayanum}
Tetramorium lucayanum West Africa & Congo Basin
81 & 133 Dorsum of head with dense coarse irregular longitudinal rugulae, spaces between narrow and with strong ground-sculpture; postpetiole longitudinally rugulose; TL 3.1-3.3 mm; blackish-brown to black

{Tetramorium versiculum}
Tetramorium versiculum Ivory Coast, Ghana & Benin
capense-group Node of petiole broader than longer in dorsal view
- With long frontal carinae
134 Erect hairs long and acute; postpetiole strongly rugulose; TL 3.6-4.1 mm; uniform mid-brown
{Tetramorium amatongae}
. .
. {Tetramorium amatongae} Tetramorium amatongae Mozambique
135 Erect hairs short & blunt; postpetiole reticulate-punctate; TL 3.3-3.6 mm; uniform glossy mid-brown, gaster darker
{Tetramorium lobulicorne}
. .
. {Tetramorium lobulicorne} Tetramorium lobulicorne Zimbabwe
- With widely separated and relatively short frontal carinae
102 & 160 Small species with minute eyes; very short frontal carinae; long scapes SI 85-91; alitrunk dorsum with abundant short hairs and very dense reticulo-puncturation; TL 2.3-2.9 mm; yellowish-brown to mid-brown
Tetramorium semireticulatum
Tetramorium semireticulatum Zimbabwe
- Medium-sized with small eyes; frontal carinae reach about posterior of eyes
131 Alitrunk dorsum with distinctive very short stout blunt hairs; TL 3.9 mm; light yellowish-brown
{Tetramorium dominum}
. .
. {Tetramorium dominum} Tetramorium dominum South Africa
135 Alitrunk dorsum reticulate-punctate, with longish erect hairs; TL 3.8-4.3 mm; yellowish-red sometimes darker, gaster brownish
{Tetramorium capense}
. .
. {Tetramorium capense} Tetramorium capense South Africa
return to start of key stage

SUB6 Anterior clypeal margin entire without any sign of a median notch or impression
Mandibles longitudinally striate and node of petiole with smooth curve from anterior to dorsum plus incurved posterior face, TL 3.7 mm plus
Otherwise next stage of key next species group
quadridentatum-group complex-A -
162 Propodeum with minute denticles at upper angle; TL 3.7 mm; uniform yellowish-brown
Tetramorium unicum
Tetramorium unicum Cameroun & Zare
137 Propodeum with moderate triangular teeth; mandibles with 3 teeth followed by 6-7 denticles; TL 4.1-5.9 mm; colour variable yellowish-brown to blackish-brown
{Tetramorium quadridentatum}
. .
type worker - yellow-brown
Tetramorium quadridentatum type

commodum variant - dark coloured
{Tetramorium quadridentatum} Tetramorium quadridentatum West Africa & Congo Basin
137 Similar but smaller with coarser sculpturation; mandibles with 3 teeth followed by 4 denticles; TL 3.7-3.9 mm; uniform yellowish-brown
{Tetramorium viticolum}
. .
. {Tetramorium viticolum} Tetramorium viticolum Kenya & South Sudan
SUB7 Propodeum with a pair of elongate spines; TL at least 3.0 mm
Otherwise next stage of key sub-section
Dorsal (hind surface) of tibiae with erect or suberect hairs or pubescence;
Otherwise next stage of key
{Tetramorium amissum tibia}{Tetramorium aculeatum}
Occipitum rugo-reticulate
86 Mandibles smooth; TL 4.8-5.2 mm; yellowish-brown, gaster darker
{Tetramorium magnificum}
. .
. {Tetramorium magnificum} Tetramorium magnificum Ivory Coast
89 Mandibles longitudinally striate; TL 2.6-3.0 mm; erect hairs blunt and almost all shorter than the maximum diameter of the eye; petiole and postpetiole finely rugulose dorsally; uniform medium to dark brown
Tetramorium longoi

Tetramorium longoi South Africa
NA Mandibles striate; TL 3.3 mm; erect hairs fine and all equal to or longer than the maximum diameter of the eye; red-brown, gaster darker
{Tetramorium n sp Cameroun fk 06}
Tetramorium n sp Cameroun fk 06 Cameroun
camerunense-group - lucayanum-complex (member) Occipitum smooth
89 TL 3.5 mm; glossy dull yellow, gaster dark brown
{Tetramorium amissum}
. .
. {Tetramorium amissum} Tetramorium amissum Zare
Dorsal (hind surface) of tibiae without erect or suberect hairs or pubescence
quadridentatum-group - complex-C (ungrouped) Eyes large, diameter > 0.30 X HW
42 TL 4.7-5.1 mm; dull red or reddish-brown
{Tetramorium simulator}
. .
. {Tetramorium simulator} Tetramorium simulator Zimbabwe
flabellum-group (part) Eyes smaller, diameter < 0.26 X HW
?saginatum-complex Shorter scapes (SI 80-85), relatively broad heads and strongly developed frontal carinae; clypeus with median carina plus lateral longitudinal weak carinae
148 Base of first gastral tergite sculptured with fine dense costulation; TL 3.3-3.7 mm; blackish-brown, first gastral tergite lighter
{Tetramorium pylacum}
. .
. {Tetramorium pylacum} Tetramorium pylacum Ivory Coast & Cameroun
151 Base of first gastral tergite unsculptured except for hair pits giving rise to stout hairs; TL 2.8-3.2 mm; uniform dark brown
Tetramorium saginatum
Tetramorium saginatum Angola
coloreum-complex Relatively short scapes (SI 77-83), relatively broad heads
142 Unicolorous very dark blackish brown; TL 3.1-3.3 mm
{Tetramorium invictum}
. .
. {Tetramorium invictum} Tetramorium invictum Ivory Coast
- Bicoloured, black (or dark brown) and yellow
57 Disc of postpetiole smooth and shining; mandibles smooth; TL 3.2-3.4 mm
{Tetramorium postpetiolatum}
. .
. {Tetramorium postpetiolatum} Tetramorium postpetiolatum Zare
57 Disc of postpetiole longitudinally sculptured; mandibles finely striate; TL 3.0-3.6 mm
{Tetramorium coloreum}
. .
. {Tetramorium coloreum} Tetramorium coloreum Congo Basin
granulatum-complex With blanketing reticulo-punctate sculpture on head, alitrunk and pedicel
42 With bizarre short, flattened hairs; TL 3.4-3.6 mm; dull red, gaster dark brown
{Tetramorium bellicosum}
. .
. {Tetramorium bellicosum} Tetramorium bellicosum Nigeria
148 With fine dense coat of short erect hairs; TL 3.5-3.7 mm; dull red, gaster slightly darker
{Tetramorium granulatum}
. .
. {Tetramorium granulatum} Tetramorium granulatum Nigeria
return to start of key stage

SUB8 Propodeum with at most a pair of short triangular teeth
Mandibles striate (not always obvious), most with short blunt hairs
Otherwise next stage of key next species group
simillimum-group Alitrunk dorsum with short blunt hairs, if any
if no hairs then eyes large, diameter > 0.29 X HW
oculatum-complex Large eyes and (probably) 2-4 elongated curved, hooked hairs on underside of head
Otherwise next stage of key next complex
- Uniform pale yellow
(as T. (Tet.) arnoldi)
Propodeum unarmed; alitrunk dorsum without hairs; TL 2.8-3.0 mm
{Tetramorium incruentatum}
. .
. {Tetramorium incruentatum}
Tetramorium incruentatum Zimbabwe
168 Propodeum unarmed; erect hairs present on dorsal alitrunk; TL 2.8-2.9 mm
{Tetramorium berbiculum}
. .
. {Tetramorium berbiculum} Tetramorium berbiculum Zimbabwe
168 With small but well-developed propodeal teeth; TL 2.5-2.7 mm; gaster usually darker
{Tetramorium luteolum}
. .
. {Tetramorium luteolum} Tetramorium luteolum Zimbabwe
- Uniform dark brown
- Base of gastral tergite with a band of shagreening
170 Very large eyes; TL 2.4-3.2 mm
{Tetramorium oculatum}
. .
. {Tetramorium oculatum} Tetramorium oculatum Zimbabwe
170 Moderate sized eyes; thick silvery hairs conspicuous; TL 2.9-3.2 mm
{Tetramorium argenteopilosum}{Tetramorium argenteopilosum}
. .
. {Tetramorium argenteopilosum} Tetramorium argenteopilosum Zimbabwe
- Base of gastral tergite without a band of shagreening and without silvery hairs
171 Scapes relatively long (SI 80-87); metapleural lobes sharp; TL 2.8-3.0 mm
{Tetramorium bevisi}
. .
. {Tetramorium bevisi} Tetramorium bevisi Lesotho
171 Scapes relatively short (SI 71); metapleural lobes rounded; TL 2.7 mm
{Tetramorium krynitum}
. .
. {Tetramorium krynitum} Tetramorium krynitum Namibia
simillimum-complex Smaller eyes (max 0.27 HW)
- Head with dense reticulo-puncturation
Otherwise next stage of key next sub-complex
177 With appressed hairs behind the eye; TL 1.9-2.1 mm; bright uniform yellow
{Tetramorium rhetidum}
. .
. {Tetramorium rhetidum} Tetramorium rhetidum West Africa & Congo Basin
- With a single stout hair immediately behind the eye
176 Yellowish, thorax and head reddish, gaster paler; TL 2.2-2.5 mm
{Tetramorium delagoense}
. .
. {Tetramorium delagoense} Tetramorium delagoense Mozambique
revived from synonymy
Bolton (1995)
Rust-red, head lighter, gaster darker; TL 2.5 mm
{Tetramorium intextum}
. .
. {Tetramorium intextum} Tetramorium intextum East Africa & Congo (?)
revived from synonymy
Bolton (1995)
Dark yellow brown to black
{Tetramorium zambezium}
Tetramorium zambezium Forests of West & Central Africa
- Without a single stout projecting hair immediately behind the eye, either hairless or with a number of minute appressed hairs behind the eye
178 Yellowish- to light brown, gaster darker; generally smaller, TL 2.0-2.7 mm
{Tetramorium simillimum - Bolton}
. .
. Egypt specimen
{Tetramorium simillimum Egypt}
. .
. Note - West African specimens with finer erect hairs
{Tetramorium simillimum}
Tetramorium simillimum Gabon Pan-African & tramp
178 Uniform dark brown to blackish brown; larger, TL 2.4-2.6 mm
{Tetramorium bothae}
. .
. {Tetramorium bothae} Tetramorium bothae southern Africa
- Head with no more than weak sculpturation
174 Scapes relatively long (SI 91), TL 2.2 mm; dark brown glossy
Tetramorium buthrum
Tetramorium buthrum Congo Basin
175 Scapes shorter (SI 82-83); mandibles finely shagreened ; TL 2.0-2.2 mm
{Tetramorium anxium}
. .
. {Tetramorium anxium} Tetramorium anxium Guinea & Gabon
Mandibles usually smooth
alitrunk dorsum with fine acute hairs, if any; if no hairs then eye diameter < 0.29 X HW
dumezi-group -
dumezi-complex Erect pilosity relatively sparse, short & fine
Otherwise next stage of key sub-section
. Propodeum with short acute teeth; without erect hairs on scapes or tibiae
165 with a strong median pronotal costa; head with seven rugulae between the frontal carinae; TL 3.1 mm; brownish yellow
Tetramorium pialtum
Tetramorium pialtum Ghana
165 No erect hairs on scapes or tibiae; without a median pronotal costa; TL 2.7-3.1 mm; clear pale yellow
Tetramorium dumezi
Tetramorium dumezi West Africa & Congo Basin
. Propodeal teeth reduced or absent
92 Erect hairs on scapes and hind tibiae, gaster smooth; TL 3.1-3.3 mm; light brown
{Tetramorium candidum}
. .
. {Tetramorium candidum} Tetramorium candidum Zare & Tanzania
92 Erect hairs on scapes and hind tibiae but gaster densely punctulate; TL 3.2-3.3 mm; uniform clear pale yellow
Tetramorium isipingense
Tetramorium isipingense South Africa
162 No pilosity on legs; TL 3.4 mm; uniform mid-brown
{Tetramorium elidisum}
. ,
. .
{Tetramorium elidisum}
Tetramorium elidisum Ghana
NA Without erect pilosity on legs or scapes; TL 3.7 mm; dark brown, funiculi and mandibles contrasting
Tetramorium Cameroun nsp fk um54
Tetramorium n  sp Cameroun fk um54 Cameroun
. Erect hairs variably abundant but always fine and acute
new Propodeum with small acute teeth; dorsum of head and alitrunk rugo-reticulate; TL 2.1-2.4 mm; yellow-brown
{Tetramorium amaniensis nsp Tanzania}
Tetramorium amaniensis Tanzania (Usambara Mts) - new species
meressei-complex Abundant long soft curved acute hairs forming a dense pelt; postpetiole with a high posterior face
91 Propodeum with small teeth; dorsal alitrunk weakly sculptured; TL 3.2-3.5 mm; uniform pale yellow
{Tetramorium meressei}
. .
91 {Tetramorium meressei} Tetramorium meressei Ghana & Zare
91 Propodeum angular with no teeth; dorsal alitrunk evenly sculptured; TL 3.1 mm; brown
Tetramorium psymanum
Tetramorium psymanum Ghana
return to start of key stage
2007, 2008, 2010, 2011, 2013, 2014 - Brian Taylor CBiol FSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.