Polyrhachis alexisi

AntWiki - Where Ant Biologists Share Their Knowledge
Jump to navigation Jump to search
Polyrhachis alexisi
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Formicinae
Tribe: Camponotini
Genus: Polyrhachis
Subgenus: Myrma
Species group: alexisi
Species: P. alexisi
Binomial name
Polyrhachis alexisi
Forel, 1916

Polyrhachis alexisi casent0227521 p 1 high.jpg

Polyrhachis alexisi casent0227521 d 1 high.jpg

Specimen Labels

This rare, but distinctive species is only known from the original type specimens (Bolton, 1973) and a collection from the Central African Republic (Rigato, 2016).


The only species of the alexisi group with a combination of four petiolar spines or teeth and immarginate propodeum.

Keys including this Species


Distribution based on Regional Taxon Lists

Afrotropical Region: Central African Republic, Democratic Republic of Congo (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb




The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • alexisi. Polyrhachis (Cyrtomyrma) alexisi Forel, 1916: 455, fig. 7 (w.q.) DEMOCRATIC REPUBLIC OF CONGO. Combination in P. (Pseudocyrtomyrma): Emery, 1925b: 206; in P. (Myrma): Bolton, 1973b: 346.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.


Rigato (2016) - HL 1.25, HW 1.11, CI 89, SL 1.41, SI 127, FW 0.30, FI 27, PW 1.00, WL 1.56, HTL 1.35.

Bolton (1973) - TL 4.8, HL 1.19, HW 1.00, CI 84, SL 1.26, SI 126, PW 0.89, MTL 1.26.

Median portion of anterior clypeal margin projecting as a shallow, rectangular lobe, ending laterally in a pair of acute denticles. Sides of the head straight to weakly concave in front of the eyes, gradually converging anteriorly. Eyes convex, just breaking the outline of the sides of the head in full-face view. Alitrunk short, broad, convex dorsally. Pronotum armed with a pair of short spines, marginate for about half the distance between the base of each spine and the promesonotal suture. Remainder of alitrunk not marginate, the dorsum rounding without interruption into the sides. Promesonotal suture shallow but distinct, metanotal groove absent. Propodeum unarmed, the dorsum rounding into the declivity, the two surfaces not separated by a transverse ridge or margin. Declivity of propodeum very deep, concave in profile. Petiole with a pair of dorsal spines and a pair of lateral teeth. Anterior surface of the first gastral segment concave medially.

Erect hairs absent except on the clypeus, mandibles, and gastral apex. Pubescence extremely short and sparse.

Clypeus and gaster finely reticulate. Head finely, longitudinally striate. Dorsum of alitrunk with an exceedingly fine and dense striation overlying a superficial reticulation. In dorsal view the striae are longitudinal and somewhat arched on the pronotum, divergent on the mesonotum and posteriorly convergent on the propodeum. Sides of alitrunk finely reticulate apart from the propodeum which is striate as the dorsum. Colour black, the appendages brown, and with the antenna! funiculi yellow-brown.

Type Material

Bolton (1973) - Syntype workers, CONGO (KINSHASA) (H. Kohl) (Musee d'Histoire Naturelle Genève) [examined].