The Ants of Africa
Genus Tetramorium species-groups - Part 3
Tetramorium Introduction

DIV3
Species groups
Part 3 - former Tetramorium (species with long antennal scapes)

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DIV3 12-segmented antennae (Tetramorium)
{12-segmented antenna}
SD1 Scape index 100 or more (scape longer than head width; usually surpasses occiput)
Otherwise next secondary division next secondary division
Frontal carinae extended back beyond posterior of eyes
Otherwise next stage of key next tertiary division
setigerum-group - complex-A Diameter of eye usually > 0.25 X HW; petiole node high and narrow in dorsal view
Otherwise next stage of key next species group
. With variable clavate hairs Tetramorium parasiticum queen only - South Africa
- With exceptionally long appendages; SI > 150
114 Dorsum of head and alitrunk rugulose with dense inter-rugal sculpture; TL 4.3-4.7 mm; uniform dark brown
{Tetramorium dolichosum}
Tetramorium dolichosum Zare
114 Dorsum of head and alitrunk weakly rugulose with little inter-rugal sculpture; TL 4.8-5.4 mm; dark brown
{Tetramorium perlongum}
. .
. {Tetramorium perlongum} Tetramorium perlongum Angola
- With relatively short appendages
- Propodeum with short spines
155 Sides of head behind eyes without projecting hairs; TL 3.0-3.3 mm; mid-brown
{Tetramorium praetextum}
. .
. {Tetramorium praetextum} Tetramorium praetextum Namibia
- Propodeum with long spines and strongly developed frontal carinae
138 Smooth mandibles; TL 4.0-4.1 mm; medium to dark brown, gaster darker
{Tetramorium agile}
Tetramorium agile Zimbabwe
144 Promesonotal dorsum smooth & shining; mandibles striated; TL 3.0-3.5 mm; mid- to dark brown
{Tetramorium laevithorax}
. .
. {Tetramorium laevithorax} Tetramorium laevithorax East & South Africa
- Promesonotal dorsum distinctly rugulo-punctate; mandibles striated
145 Eye diameter 0.28-0.31 X HW; smaller specimens HW at least 0.68; with numerous strong standing hairs on dorsum; TL 3.4-4.0 mm; mid- to dark brown, gaster darker
{Tetramorium setigerum}
. .
. {Tetramorium setigerum} Tetramorium setigerum East & South Africa
- Eye diameter 0.25-0.28 X HW; HW 0.58-0.67
146 & 156 Petiole node rounded as shown; striated mandibles; 3.1-3.7 mm; mid-brown or darker
{Tetramorium avium}
. .
. {Tetramorium avium} Tetramorium avium South Africa
146 Petiole node angular as shown; TL 2.9-3.4 mm; uniform dark brown
{Tetramorium frenchi}
. .
. {Tetramorium frenchi} Tetramorium frenchi South Africa & Zimbabwe
flabellum-group (part) Diameter of eye no more than 0.24 X HW; petiole node long and low in profile
flabellum-complex With long scapes (SI 90-100+) and strongly developed frontal carinae; clypeus with strong median carina and diagonal lateral carinae
149 Dorsal surfaces with bizarre fan-shaped hairs; TL 2.9-3.2 mm; dark brown
Tetramorium flabellum
Tetramorium flabellum Ivory Coast & Ghana
- Dorsal surfaces with simple, usually stout and blunt, erect hairs
150 Postpetiole dorsum less strongly sculptured than sides or petiole, with a median smooth strip; TL 2.8-3.0 mm; dark brown, gaster lighter
{Tetramorium sigillum}
. .
. {Tetramorium sigillum} Tetramorium sigillum Ivory Coast
- Postpetiole dorsum sculptured as sides and petiole dorsum
152 Light coloured, yellowish-brown; TL 3.0-3.1 mm
Tetramorium kestrum
Tetramorium kestrum Eastern & southern Africa
153 Dorsum of head with erect hairs no longer than diameter of eye; TL 3.0-3.5 mm; dark brown
{Tetramorium ataxium}
. .
. {Tetramorium ataxium} Tetramorium ataxium West Africa & Congo Basin
153 Dorsum of head with erect hairs markedly longer than diameter of eye; TL 3.4 mm; reddish-brown dark and glossy

{Tetramorium geminatum}
Tetramorium geminatum Gabon
Frontal carinae end at or forward of posterior of eyes
aculeatum-group
former Macromischoides
Petiole node high and narrow in profile, in dorsal view broader than long
Otherwise next stage of key next species group
99 Metapleural lobes elongate triangular; petiole with low node; TL 4.8 mm; dark brown
{Tetramorium 
}
. .

{Tetramorium Tetramorium rimytyum Ghana
- Metapleural lobes much reduced or absent; petiole node high and narrow in profile
. Petiole with long peduncle; erect pilosity long . .
60 & 100 Petiole with long peduncle; TL 3.2-5.4 mm +; variable forms light brown
to near black
(propodeal spines may be much reduced)
{Tetramorium aculeatum}
. .
. {Tetramorium aculeatum} Tetramorium aculeatum pan-African forests
. {Tetramorium aculeatum queen} Tetramorium aculeatum queen .
new species Overall size smaller, wing smaller; CuA cell proportionally smaller; mandibles completely smooth; head frontal area with little sculpturation; eye longer than wide (circular in aculeatum); head in profile with occiput shallowly but distinctly convex (near flat in aculeatum); distance between dorsal ocelli = 2.11 X length of ocelli (in aculeatum = 2.84); HW/width across eyes/HW = 123 (aculeatum = 118); CI = 84 (aculeatum CI = 90); funiculus segment 3-4 together shorter than segment 1 (in aculeatum 3+4 = 1); scape proportionally longer and SL greater, SI 131 (aculeatum SI = 110); pronotum dorsum with 9-10 strong parallel rugae; postpetiole in profile relatively narrow; longer erect hairs on hind legs and scapes; overall much paler orange-brown (aculeatum ranging from near black to brown
{Tetramorium robini nsp queen CAR HP}
Tetramorium robini Central African Republic - new species
. Petiole with short peduncle; erect pilosity short . .
60 &100 TL 3.7-4.7 mm; uniform light to medium brown; gaster with dense short pilosity
{Tetramorium africanum}
. .
Queen {Tetramorium africanum} Tetramorium africanum West Africa & Congo Basin
Queen only With erect hairs on gaster absent or restricted to posterior border of segments
{Tetramorium rotudatum queen}
Tetramorium rotundatum Congo Basin
sericeiventre-group Petiole node long and low in profile, in dorsal view usually longer than broad; clypeus laterally with a prominent tooth or crest
Otherwise next stage of key next species group
longicorne-complex Mandibles unsculptured; no pilosity; large eyes
41 TL 4.4-5.1 mm; dull red, gaster darker
{Tetramorium longicorne}
. .
. {Tetramorium longicorne} Tetramorium longicorne East Africa
bequaerti-complex Striated mandibles; numerous short erect hairs on scapes and tibiae of middle and hind legs
96 All over with very dense pile of short soft hairs; TL 3.3 mm; uniform dark brown
Tetramorium xuthum
Tetramorium xuthum Ghana
- Numerous short erect hairs all stout and scattered
97 Head with distinctive lug on posterior ventral corner; TL 4.3-4.6 mm; dull red
{Tetramorium bequaerti}
. .
. {Tetramorium bequaerti} Tetramorium bequaerti eastern Zare & Tanzania
- Head with rounded posterior ventral corner
98 Dorsum of head behind eyes feebly sculptured to smooth; TL 3.0-3.4 mm; reddish yellow to dull red
{Tetramorium bulawayense}
. ,
. {Tetramorium bulawayense} Tetramorium bulawayense Zimbabwe
98 Dorsum of head behind eyes strongly rugulose; TL 3.0-3.2 mm; reddish yellow to dull red
{Tetramorium hortorum}
. .
.8 {Tetramorium hortorum} Tetramorium hortorum Zimbabwe
sericeiventre-complex Striated mandibles; no erect hairs on scapes and tibiae of middle and hind legs
- Propodeal dorsum with one or more pairs of erect hairs
Otherwise next stage of key
- Short, stout, erect hairs projecting on sides of head behind the eyes
121 Densely hairy; promesonotum dorsum coarsely longitudinally rugose;
TL 4.1 mm; uniform dark brown, with reddish tint
{Tetramorium asetyum}
. .
. {Tetramorium asetyum} Tetramorium asetyum Nigeria
121 Densely hairy; promesonotum dorsum smooth or nearly so: TL 3.6-3.7 mm; light brown, with reddish tint, gaster darker
Tetramorium petersi
Tetramorium petersi Namibia
- Without erect hairs projecting behind the eyes
122 Propodeal dorsum with only a single pair of hairs; first gastral tergite with blunt hairs; TL 4.0-4.3 mm; dull red, gaster blackish-brown
{Tetramorium khyarum}
Tetramorium khyarum Nigeria round western savannah to Botswana
122 Propodeal dorsum with several pairs of erect hairs; first gastral tergite with slender acute hairs TL 3.8-4.4 mm; dull red or reddish-brown, gaster darker
{Tetramorium sepositum}
. .
. {Tetramorium sepositum} Tetramorium sepositum Zimbabwe & South Africa
- Without erect hairs on propodeum
123 Dorsal alitrunk very coarsely rugose, spaces shining; TL 3.8-4.5 mm; dark red, gaster blackish, glossy
Tetramorium gladstonei
Tetramorium gladstonei Zimbabwe
124 Dorsal alitrunk and head with fine rugulae and dense reticulate puncturation; base of gaster usually completely finely sculptured, matt and dull; TL 3.3-4.4 mm; colour dull red variable from yellowish through to dark, gaster usually darker
{Tetramorium sericeiventre}
. .
. {Tetramorium sercieiventre} Tetramorium sericeiventre Pan-african
124 Dorsal alitrunk and head feebly sculptured at most; base of gaster smooth and shiny; TL 3.6-4.0 mm; colour dull red variable from yellowish through to dark, near black
{Tetramorium quadrispinosum}
. .
. {Tetramorium quadrispinosum} Tetramorium quadrispinosum southern Africa & Madagascar
Queen only inquiline found in nests of sepositum and sericeiventre Tetramorium microgyna Southern Africa
setigerum-group - complex-B Petiole node high and narrow in profile, in dorsal view usually longer than broad; clypeus laterally not strongly modified
- Propodeum with no more than denticles; weak frontal carinae
118 & 157 Sides of head behind eyes with projecting hairs; pronotal dorsum sculptured: TL 3.2-3.8 mm; yellowish-brown to mid-brown
Tetramorium doriae
Tetramorium doriae Ethiopia also Arabian Peninsula
118 & 157 Sides of head behind eyes with projecting hairs; pronotal dorsum mostly unsculptured; TL 3.4 mm; uniform mid-brown
{Tetramorium gracile}
.
. {Tetramorium gracile} Tetramorium gracile Ethiopia
- Propodeum with long spines but weak frontal carinae
141 Longitudinal rugulae on head without cross-meshes, almost smooth between rugae; TL 3.6-4.1 mm; dark brown, appendages yellow
{Tetramorium metatactum}
. .
. {Tetramorium metatactum} Tetramorium metatactum Kenya
141 Longitudinal rugulae on head with cross-meshes, distinct ground-sculpture between rugae; TL 3.4 mm; glossy blackish-brown, appendages pale yellow
Tetramorium youngi
Tetramorium youngi Angola
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Contents
2007, 2008, 2010, 2011, 2013, 2014, 2016 - Brian Taylor CBiol FRSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.

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