The Ants of
Egypt SUBFAMILY MYRMICINAE - Genus Messor (Forel) |
Raised to genus by Bingham, 1903, includes members previously placed in Cratomyrmex Emery.
In Tribe PHEIDOLINI.
Diagnostic Features - Granivorous ants, most strongly polymorphic. Ventral surface of head with a psammaphore (a basket-like array of long, curved hairs beneath the head, used to carry sand). Mandibles strongly curved, usually dentate in smaller workers. Antennae 12-segmented. Propodeum armed with a pair of blunt teeth. Node of petiole emarginate above in large workers. Illustrations of West African species are not available so those below are given as a guide.
The original genus definition, as a subgenus of Aphaenogaster, Forel (1890a: lxviii) is at . Emery's (1892d) definition of Cratomyrmex is at .
André (1883a: 350) gave a key to the species then known from Europe and North Africa this is at . Finzi (1936: 160) gave a key to the species then known from Egypt; this is at .Key to workers from Egypt - derived largely from Finzi (1936)
1 | Funiculus with last four segments elongated; body slender and smooth; colour yellow, gaster brownish; TL max 7.5 mm | North Africa through Sinai to Syria - rufotestaceus |
-- | Funiculus with last four segments not elongated; colour other than yellow | 2 |
2 | First segment of funiculus shorter than second | 3 |
-- | First segment of funiculus at least as long as second | 4 |
. | First segment of funiculus shorter than second | . |
3 | TL 7-16 mm; declivity of mesonotum obviously convex and declivity of propodeum abrupt (105-110°); propodeum with distinct teeth | Across North Africa into Syria - arenarius |
-- | TL
12-16 mm; posterior declivity of mesonotum less convex and of propodeum
less abrupt (120-130°); propodeum with teeth reduced to denticles;
petiole with lower profile than most other species; head, alitrunk and
pedicel matt, densely reticulo-punctate; sides of head longitudinally
striate, plus a detached pair between the frontal carinae running
towards the vertex; generally red, edges of clypeus and frontal carinae,
scape, sometimes lower alitrunk, part of gaster blackish-brown to black,
appendages lighter (media shown) |
Egypt - niloticus |
. | First segment of funiculus at least as long as second | . |
4 | Occiput with more or less visible transverse striations, alitrunk deeply striated; petiole profile a low triangle; gaster smooth and shiny; TL 6 mm | rugosus |
-- | Occiput with no or only longitudinal striations | 5 |
5 | Propodeum with teeth or spines | 6 |
-- | Propodeum unarmed or with minute denticles/spines (when generally red in colour) | 9 |
. | Propodeum with at least pronounced tubercles | . |
6 | Propodeum with large teeth (not spines), quite strong but obtuse; body form slender; head and gaster brilliantly shiny; generally ebony black but alitrunk may be very slightly reddish in minor workers, tibiae & tarsi yellowish; alitrunk quite deeply rugose; opaque; TL 4.1-10 mm - NOTE - the foregoing based on Forel's description, later authors appear to have the teeth reduced to tubercles; the specimen shown has broad propodeal teeth | (semirufus ebeninus) Egypt to Syria - ebeninus |
-- | Propodeum with distinct spines | 7 |
7 | At least the alitrunk reddish; gaster black; pronotum densely granular, petiole finely rugose, gaster weakly granular basally, slightly shiny; propodeum with raised spines, sometimes arcuate; small TL max 6 mm | Algeria east to Egypt - aegyptiacus |
-- | Wholly black | 8 |
8 | Propodeum with flat spines, ends downturned; occipitum shiny, with sparse small rounded fossettes | (aegyptiacus foreli) Algeria, Tunisia and Sinai - foreli |
-- | Head with longitudinal striations reaching the occiput; longer propodeal spines with a narrower base than type aegyptiacus | Egypt only - aegyptiacus felah |
-- | Head black, alitrunk usually reddish with superficial rugosity, sometimes lightly shiny; appendages reddish to rust [Santschi, 1927c: 240], reported from Alexandria with reservations by Finzi (1936) - aralocaspius (Ruzsky, 1902c: 20, worker) occurs only in east-central Asia and minor (André, 1883b: 355, worker & queen) from North-east Africa, other than the type form from Italy, type location from Corsica (André, 1883b: 355, worker & queen) - rather small, TL maximum 7.0 mm | [questionable
diagnosis, possibly a one-off immigrant minor from Italy] -
Egypt (Alexandria), Turkestan - minor aralocaspius tamerlani BUT see aegyptiacus |
-- | Description imprecise (Finzi, 1936: 158); head flatter, longer psammophore; eyes larger, length = the distance eyes forward of occiput; much longer propodeal spines than type aegypticaus; head reddish, alitrunk dark brown (Forel, 1913d, as race of aegyptiacus); TL 4-12 mm | Egypt - aegyptiacus sahlbergi |
-- | Unicolorous black; TL 8.8 (minor worker ?); head with dense granulate sculpturation | Egypt - eglalae |
Propodeum unarmed or with minute spines/denticles | . | |
9 | Whole
of body covered with dense pilosity; head and alitrunk strongly striate,
matt; propodeum unarmed; varies from yellow brown to brown black, with
appendages all reddish; TL 3.5-10 mm |
France east to Central Asia - structor |
-- | Pilosity sparse to none | 10 |
10 | Tl 3-6 mm; head of major relatively small; type form with brown head (queen black); alitrunk finely sculptured; basal segment of gaster glabrous, smooth and shiny; scape reaches occiput; clearly higher petiole node | Tunisia, Algeria & "Arabian Desert near Cairo" - medioruber |
-- | subspecies generally red; propodeum seemingly with angular tubercles or minute spines rather than edentate | medioruber ssp maurus |
-- | Petiole only moderately high | 11 |
11 | Propodeum with obtuse transition from dorsum to declivity; apparently overall darker than type barbarus and head not lighter/more red than rest; | Syria, Crete & Sinai (?) - concolor |
-- | Propodeum with acute transition from dorsum to declivity | 12 |
12 | Type head particularly occiput smooth or near smooth and shiny, alitrunk quite heavily sculptured; propodeum often unarmed; TL 4-12 mm | southern Europe and circum-Mediterranean - barbarus sensu lato |
-- | Overall brown-red or brownish-red; head reddish, patches on head and mesonotum, also parts of legs and gaster more brown, antennae and rest of legs clear brownish red; propodeum with subvertical declivity and distinct metanotal groove; TL 5-10 mm; | (semirufus maculifrons) Egypt, Syria into Caucasus - maculifrons |
-- | Overall smooth or near smooth and shiny, alitrunk weakly sculptured; propodeum often unarmed; TL 4-8.5 mm; unicolourous red-brown | Egypt & Tunisia - binodis |
©2005,
2006, 2008, 2009, 2010, 2015, 2019 - Brian Taylor CBiol FRSB FRES 11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K. |
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