The Ants of Africa
Contents - Myrmicinae - MYRMICINAE Introduction

Genus Decamorium Forel (1913a: 121)


Diagnostic Features - The key feature is the 10-segmented antenna, with a 3-segmented club.

Forel's (1913a) genus description is at {original description}. Arnold (1917: 349) gave a translation, this is at {original description}. Bolton's (1976) review is at {original description}.

Bolton (1976, 1995) listed only two species.

Note: Hita Garcia & Fisher (2014) (see opine that Decamorium should be subsumed under Tetramorium, with Decamorium being a "species-group"

Key following Hita Garcia & Fisher (2014)
Dorsum of promesonotum with conspicuous longitudinally rugose/rugulose sculpture
Dorsum of promesonotum unsculptured, smooth, and usually very shiny
Decamorium raptorSlightly smaller species, TL ca 3.2 mm, (WL 0.88–0.93); HL 0.64-0.68, HW 0.53-0.56;  propodeum armed with shorter, triangular, and acute teeth (PSLI 10–11); dorsum of promesonotum longitudinally rugulose with very little ground sculpture, lateral pronotum mostly unsculptured and shiny, only dorsally longitudinally rugulose; generally of uniform dark brown colour; rainforest species
Cameroun, Nigeria - raptor
Decamorium uelenseSlightly larger species (WL 0.98–1.06); HL 0.67-0.72, HW 0.54-0.59; propodeum armed with longer, triangular to elongate-triangular, and acute teeth (PSLI 16–18); dorsum of promesonotum and lateral pronotum strongly longitudinally rugose with distinct punctate ground sculpture; strongly bicoloured species with dark brown or black gaster contrasting with light brown to reddish brown on remainderof body; savannah species
West Africa & Congo Basin - uelense
Decamorium decem typeGenerally larger species (WL 1.02–1.16); HL 0.71-0.74, HW 0.59-0.62; propodeal teeth relatively longer (PSLI 17–19); petiolar node in profile relatively higher, in profile 1.2 to 1.3 times higher than long (LPeI 77–82); strongly bicoloured species with dark brown or black gaster contrasting with light brown to reddish brown remainder of body
Kenya, Tanzania, Zimbabwe - decem
Generally smaller species (WL 0.85–0.98); propodeal teeth relatively shorter (PSLI 9–13); petiolar node relatively lower, in profile around 1.0 to 1.2 times higher than long (LPeI 86–100); usually of uniform brown colour, if bicoloured, then only slightly so and never as well developed as above
Decamorium ultorSmaller eyes (OI 33–36); HL 0.62-0.70, HW 0.48-0.58; body colouration uniformly light brown to chestnut brown
Cameroun & East Africa - ultor
Decamorium venatorLarger eyes (OI 37–40); HL 0.64-0.71, HW 0.51-0.59; body colouration uniformly dark brown to black, always darker than above.
Liberia east to Uganda - venator
Contents MYRMICINAE Introduction
2007, 2011, 2012, 2015 - Brian Taylor CBiol FSB FRES
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