Aphomomyrmex

Identification
Snelling (1979) - WORKER: Polymorphic; head rectangular; antenna nine-segmented, without distinct apical club; ocelli well below occipital margin. FEMALE: Antenna ten-segmented, without distinct apical club; head about one-third longer than wide, parallel-sided; frontal carinae separated by more than their length; atria of propodeal spiracle and metapleural gland large, nearly circular, latter without conspicuous guard hairs. MALE: Antenna ten-segmented, without distinct apical club; eye large, occupying most of side of head; ocelli large; frontal carinae obsolete; pygostyles present; mandible tridentate.

Nomenclature

 *  APHOMOMYRMEX [Formicinae: Plagiolepidini]
 * Aphomomyrmex Emery, 1899e: 493. Type-species: Aphomomyrmex afer, by subsequent designation of Wheeler, W.M. 1911f: 159.
 *  APHOMYRMEX  Ashmead, 1905a: 111, incorrect subsequent spelling of Aphomomyrmex: Bolton, 1995b: 20.

Ce genre se rapproche de Myrmelachista et encore davantage de Dimolphomyrmex. Il differe du premier par ses antennes ne formant pas de massue differenciee, du second par la forme et la position des yeux par rapport aux aretes frontales, ainsi que par le faible developpement de ces dernieres. Je l'etablis sur une espece nouvelle de l'Afrique occidentale, dont j 'ai recu 3 ouvrieres et plusieurs femelles dont deux encore unies en accouplement avec le mâle. Je crois, malgre la difference de nombre des articles des antennes, que la queen se rapporte a la worker. Les differences dans la forme de la tete et du petiole sont de l'ordre de celles que l'on observe dans le genre Myrmelachista.

Je rapporte au meme genre l'espece que j'ai decrite autrefois sous le nom de Dimorphomyrmex Andrei (=Cladomyrma andrei) d'apres la queen seule provenant de Borneo. Elle differe de l'espece africaine par les arêtes frontales beaucoup plus rapprochees l'une de l'autre, ce qui fait que l'epistome ne s'avance que fort peu entre elles. Les antennes n'ont que 8 articles. La position des yeux est comme chez A. afer et non pas comme chez Dimorphomyrmex. Il est probable que la queen de D. Janeti (=Gesomyrmex chaperi) a les yeux reniformes places comme chez la worker.

Worker
Tete courte. Antennes de neuf articles (ou moins?) le 1st article, du funicule plus long que le 2nd, les suivants graduellement epaissis, sans massue differenciee. Epistome un peu prolonge en arc entre les aretes frontales, court, faiblement saillant en avant; pas d'aire frontale distincte. Yeux ovales, places notablement en dehors des aretes frontales qui sont ecartees l'une de l'autre ; ocelles distincts. Mandibules de forme ordinaire. Corselet constitue sur le type de Plagiolepis, le postscutellum formant un bourrelet transversal. Ecaille mince. Les poils dresses sont fins, pointus, pas branchus au bout.

Snelling (1979) - Polymorphic, HW of largest worker about twice that of smallest; head rectangular. Mandible with five or six teeth along apical margin; basal tooth indistinct and greatly offset along basal margin. Maxillary palp five-segmented, labial palp three-segmented. Median lobe of clypeus broader than long, moderately convex longitudinally and transversely, basal margin below level of upper margin of antennal sockets; lateral margin confluent with antennal socket; apical margin of median lobe slightly projecting, subtruncate to weakly convex. Antennal scape not reaching occipital margin, broadened at apex, flagellum eight-segmented, only first and last segments longer than broad; gradually thickened apicad, without distinct club. Eye slightly higher than broad; placed slightly below middle of side of head; distance between eye and antennal socket slightly greater than distance between eye and head margin in frontal view. Ocelli present, distinct in large workers, minute is smallest workers, placed well below Occipital margin in frontal view. Occipital margin broadly and weakly concave in largest workers, more narrowly and abruptly concave in smallest.

Mesosoma stout, about twice longer than wide, widest across pronotum; pronotum about twice wider than length along midline. Promesonotal suture distinct. Mesonotum, in dorsai view, wider than long; convex in profile and abruptly descending into metanotal depression. Metanotal spiracles slightly elevated; metapleural gland very large, atrium large, circular, not provided with guard hairs. Propodeum broader than long in dorsal view, sides gently convex; declivity flat in profile, about twice longer than basal face; spiracle large.

Profemur stout. Middle tarsal segments short, broader than long. Tarsal claws simple.

Node of petiole scaliform; spiracle minute, near base of scale.

Acidopore with conspicuous fringe of long, curled hairs.

Queen
Tete plus allongee, construite d'ailleurs comme chez la worker. Antennes de 8 ou 10 articles. Corselet etroit, allonge. Ecaille du petiole epaisse, basse. Nervures des ailes comme chez Plagiolepis.

Snelling (1979) - Head distinctly longer than wide, with straight, subparallel sides and straight occipital margin in frontal view. Eye large, lateral. Ocelli large. Antenna about as in worker, but flagellum nine-segmented. Mandible as in worker but basal tooth larger and set further basad.

Mesosoma normal for alate forms, somewhat flattened in profile; mesonotum flattened, about as broad as long. Scutellum flattened and on same plane as mesonotum. Metanotum and propodeum, in profile, strongly oblique, latter without distinct basal face.

Legs as in worker.

Forewing with a single submarginal cell; vein m-cu absent; fringe hairs present except along apical margin. Hindwing with cu-a far basad of r-m; 1A ending at cu-a; fringe hairs long, present along posterior margin.

Node of petiole low, thick; from above, about twice wider than long.

Gaster somewhat elongate, acidopore as in worker.

Male
Le male est beaucoup plus petit que la queen. Les antennes ont 10 articles comme chez la queen (dans l'unique espece dont le male soit connu), le scape plus long que la moitie du funicule. Les mandibules sont dentees. Les aretes frontales plus rapprochees l'une de l'autre. L'ecaille du pedicule est a peu pres comme chez la queen. Armure genitale bien developpee: stipes en lame falciforme, la volselle grele, plus longue que la lacinie qui est distincte.

Snelling (1979) - Head, across eyes, distinctly broader than long. Eye massive, occupying most of side of head, but distance between eyes greater than eye width in frontal view. Ocelli enlarged, ocellocular distance less than maximum diameter of anterior ocellus. Mandible with three widely spaced teeth, apical tooth much broader and longer. Scape more slender than that of female, flagellum ten-segmented.

Mesosoma, from above, about one-third longer than wide; in profile, about one-third longer than high. Mesonotum wider than long. Scutellum, in profile, convex. Propodeum about as in female.

Legs slender. Wings as in female.

Node of petiole, in profile, bluntly triangular; from above, about as wide as long.

Gaster robust. Pygostyles present. Subgenital plate deeply excised. Paramere conspicuously longer than basal width, apex acute; ventral lobe of aedeagus nearly straight; edentate, basal angle dentiform.

Type Material
Snelling (1979) - It is possible that the type of Aphomomyrmex muralti (=Aphomomyrmex afer) is from Cameroon and not from Natal as stated by Forel. In the Forel collection are the two Cameroon workers collected by von Muralt. The type of A. muralti has the notation "Natal (v. Muralt)." but only on the identification label. That notation appears to have been made at a different time and with a different pen than the identification. It is not inconceivable that "Natal" is an error.