The Ants of Egypt SUBFAMILY MYRMICINAE - Genus Messor (Forel)

Genus Messor (Forel, 1890a)

With 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 .

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

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