SUBFAMILY MYRMICINAE - Genus Oligomyrmex
Key to minor workers
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The Ants of
Africa SUBFAMILY MYRMICINAE - Genus Oligomyrmex Key to minor workers |
| Contents - Myrmicinae - MYRMICINAE Introduction |
| ¤ | Queen only known; subgenus Crateropsis, head with unique sculptured dorsal concavity | Kenya - elmenteitae |
| -- | subgenus Sporocleptes | -- |
| -- |  TL 1.8-1.9 mm; antenna 11-segmented with a distinctive
two-segmented
club, the penultimate segment cup or goblet shaped; mandible with
six-teeth but centre pair reduced, leaving two large apical and two
large distal teeth; pronotum with rounded anterior margin; propodeum
with strong superior spines, declivity with lamellate lateral
margination and lower teeth |
Possibly a separate genus Sporocleptes
Arnold |
| -- |  (description for nicotianae)
TL 1.9 mm; colour
ochreous (darker in politus), gaster lighter |
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| . |  |
Kenya & Zimbabwe - politus |
| -- |  Bernard
in genus Nimbamyrma; TL 1.8 mm; colour bright yellow |
Guinea - probable junior synonym of politus villiersi |
| -- |  TL
1.0 mm; head only 1.14 times longer than wide, with markedly convex
sides and long frontal carinae; propodeal teeth short but acute |
Kenya probable junior synonym of politus - punctatus |
| -- | Oligomyrmex proper |
-- |
| -- | Antennae 9-segmented | subgenus Oligomyrmex |
| -- | Antennae 10-segmented (note debilis 9-segmented) | subgenus Aeromyrma |
| -- | Antennae 11-segmented | subgenus Aneleus |
| -- | subgenus Oligomyrmex - antennae 9-segmented | -- |
| ¤ | Major only described | Uganda - convexus |
| ¤ | Major only known | Chad - diabolicus |
| ¤ | Description inadequate; TL 0.98 mm; separation by major | Nigeria - new species - boltoni |
| 1 |  TL 0.8 mm; head a
little longer than broad, longer than in alluaudi and less
enlarged behind; the scape nearly
attains the posterior fourth of the head; mandibles of four teeth;
alitrunk broad in front and more marginate than in alluaudi;
basal face of the propodeum clearly broader than long, with the teeth
moderate, somewhat broader at the base than long; petiole a little
longer than high and a little broader at the summit than in alluaudi;
postpetiole rounded, narrower. Head, propodeum, and sides of the
petiole matt, densely and finely reticulate-punctate, the remainder
smooth and shining; colour reddish yellow |
Angola & Gabon - angolensis |
| -- | TL 1.0-1.1 mm | 2 |
| 2 |  Pilosity
short but copious; TL 0.9 mm; head slightly longer than wide; lateral
alitrunk, head and promesonotum shiny; propodeum and pedicel densely
punctate; colour yellow-brown, head more yellow |
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| . |  |
Ethiopia & Gabon - erythraeus |
| -- | Pilosity thin and sparse | 3 |
| 3 | Propodeum with distinct triangular teeth | 4 |
| -- | Propodeum with no more than small points | 5 |
| 4 |  TL 1.1 mm; head
nearly 1.2 longer than wide; mandibles
5-toothed; anterior clypeal margin produced as a sinuate lobe over base
of mandibles; eyes minute; frontal lobes well developed and convex not
concealing antennal insertions; propodeum with small triangular teeth;
sublucid, all except pronotum and gaster with fine dense puncturation;
colour yellowish-brown, antennae and legs paler |
CAR - donisthorpei
or Sudan - santschii |
| -- |  TL
1.1 mm; head less than 1.2 times longer than wide; mandibles with fine
acute teeth; propodeal spines short and triangular, declivity laterally
carinate; sublucid, densely punctate except on gaster, pronotum and
dorsum of pedicel nodes; brownish-yellow |
Zaïre - frontalis |
| 5 |  TL
1.0-1.1 mm; head one-eighth longer than wide; propodeum sub-dentate;
mostly smooth, propodeum and lateral mesonotum reticulo-punctate |
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| . |  |
Congo & Zaïre - latro |
| -- |  TL
1.0-1.2 mm; head 1.25 longer than wide; propodeum dorsum convex, teeth
feeble; petiole short and high; shiny except for dense, coarse
puncturation on propodeum; colour yellowish-brown, head and medial
gaster darker (close to erythraeus) |
. |
| . |  Non-type image |
Kenya & Uganda - thoracicus |
| -- |  TL
1.09, HL 0.37, HW 0.32, SL 0.23, PW 0.21; CI 88, SI 70; head
sub-circular; mostly smooth and shiny; weak sculpture on propodeum |
Zimbabwe - rhodesianus |
 |
subgenus Aeromyrma - based on Weber (1952) -
antennae 10-segmented |
-- |
| ¤ | Major only known | Botswana - africanus |
| ¤ | Major only known | Zaïre - petulcus |
| 6 | TL < 1 mm | 7 |
| -- | TL > 1 mm | 10 |
| 7 | Antennae 10-segmented | 8 |
| -- |  Antennae
9-segmented, head one-sixth longer than broad, scape attains posterior
fifth of head; postpetiole 1.5 times broader than long |
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| . |  |
Guinea & Gabon - debilis |
| 8 |  Mandibles 4-toothed; TL 0.9
mm; scape attaining posterior third of head; head no more than lightly
sculptured; postpetiole almost 2 times broader than long (major
antenna is 9-segmented) |
Kenya - jeanneli |
| -- | Mandibles 5-toothed | 9 |
| 9 |  TL 0.8-1.0 mm; head a little
longer than wide; mandibles 5-toothed, eyes minute; scape slightly
surpassing posterior third of head; pronotum with anterior angles
rounded; propodeal spines longer than one-third their basal interval;
matt with a greasy reflection, mostly reticulate-punctate; colour
entirely dull yellow; antennae & legs paler |
Kenya - alluaudi |
| -- |  TL 0.8 mm; head
except frons densely
reticulate; propodeal declivity with a translucent lamella on each
side, that dentate at both ends; postpetiole twice as broad as long;
colour yellow, appendages paler |
Ghana - vorax |
| 10 |  Totally
without eyes; TL 1.0-1.2; mandibles with 5 teeth; postpetiole 1.3 times
broader than long; head
smooth and shiny |
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| . |  |
South Africa - arnoldiellus |
| -- | Eyes present, even if atrophied | 11 |
| 11 | TL 1.1-1.2 mm | 12 |
| -- | TL 1.5 mm | 16 |
| 12 | Propodeum without spines | 13 |
| -- |  Propodeum
with distinct spines, TL 1.1 mm, HL 0.42 HW 0.31; mandibles with 5
teeth; colour brown |
Zaïre - acutus |
| 13 | Head near rectangular in full face view, with straight sides | 14 |
| -- | Head more ovate with convex sides | 15 |
| 14 |  Mandibles
4- or 5-toothed; TL 1.1-1.3 mm; scape attaining posterior quarter of
head; no propodeal lamellae; colour reddish-yellow, gaster more brown |
. |
| . |  |
South Africa - hewitti |
| -- |  Mandibles
5-toothed; TL 1.2 mm; head a little over 1.25 times longer than broad;
postpetiole almost 1.5 times broader than petiole; propodeum marginate;
almost unsculptured; colour yellow |
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| . |  |
Zimbabwe - lucidus |
| 15 |  |
. |
| . |  |
Zimbabwe - incertus |
| -- |  TL 1.2
mm; head 1.15 times longer than wide; mandibles with 4-5 teeth;
propdeum more or less bordered; petiole node low and rounded;
postpetiole 1.3 times broader than petiole; head with some
puncturation; mesopleurae, propodeum and pedicel finely
reticulo-punctate; colour dirty-yellow |
. |
| . |  |
Mozambique - nanus |
| -- |  TL
1.1-1.2 mm; mandibles 4-toothed; propodeal dorsum flat, declivity
margined with a fine lamella; head mostly shiny, propodeum faintly
reticulate-punctate, rest shiny; colour pale yellowish-brown, antennae
and legs ochreus |
Zimbabwe - khamiensis |
| 16 |  TL
1.5 mm; head narrower; mandibles with 5 teeth; propodeum with very
small tubercle at angle; propodeum, posterior of mesonotum and petiole
node reticulate, puncturate and submatt;
colour yellow with reddish tint |
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| . |  |
South Africa - traegaordhi |
| -- |  TL 1.5 mm; head 1.17 times longer than broad;
mandibles with 5 teeth; generally smooth and shiny but mesonotum,
propodeum and petiole finely
reticulate-punctate; colour dull brownish-yellow, head darker,
appendages and apex of gaster paler; robust |
Uganda - ugandanus |
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subgenus Aneleus - antennae 11-segmented | -- |
| 17 | Propodeum with junction of dorsum and declivity angular but without teeth or spines | 18 |
| -- | Propodeum with distinct spines or teeth at
junction of dorsum and declivity |
19 |
| 18 |  TL
1.2 mm; head rectangular with straight sides; metanotal suture shallow;
propodeal teeth reduced to tubercles; densely puncturate but quite
shiny; yellow |
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| . |  |
Cameroun, CAR - diabolus |
| -- |  TL
1.4 mm; head with markedly convex
sides and long frontal carinae; head and alitrunk smooth and shiny |
Cameroun - new species cameroun FK |
| 19 | TL < 1.2 mm | 20 |
| -- | TL > 1.2 mm | 21 |
| 20 |  TL
ca 1.0-1.25 mm; (note no description ever made, thus based on soldier
and drawing) apparently pronotum with sharp straight anterior margin;
colour testaceous red |
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| . |  |
Ghana & Guinea - silvestrii |
| 21 |  TL 1.8-2.0 mm;
pedicel nodes especially petiole rounded in
profile; head slightly longer than wide, sides convex and posterior
angles sharp; mandible 5-toothed; propodeum with two small sharp spines
(as in soldier); sculpturation similar to soldier but head without
transverse rugae; sparse yellowish pilosity; colour testaceous red,
clypeus and mandible rust brown |
(? Nigeria - undetermined species) Fernando Po I. & Gabon - menozzii |
| -- |  TL 1.5 mm; head
elongate, sides moderately convex,
occipital margin concave and sharp; pronotum with sharply defined
margins; propodeum with triangular tooth on each side; petiole narrow
with post-petiole barely wider; colour reddish-yellow (note arnoldi
is TL 1.0-1.4 mm) |
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| . |  |
East & South Africa - perpusillus |
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MYRMICINAE Introduction |
© 2007, 2008, 2010, 2011, 2013, 2015 - Brian Taylor
CBiol
FSB FRES 11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K. |
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