The Ants of Africa
SUBFAMILY DOLICHODERINAE - Genus Technomyrmex - extra notes from Wheeler (1922)
Main Dolichoderinae page

Most of the following information is taken from Wheeler (1922) for Engramma - since entirely revised and re-ordered by Shattuck (1991, 1992b) with most species removed to Technomyrmex and denticulatum to Axinidris -

My feeling is that the Engramma, now Technomyrmex, were orginally separated as having a head which is distinctly heart-shaped in full-face view. Wheeler (1922) defined the workers of Engramma as:- Small, monomorphic, with the head more or less excised behind, and the anterior border of the clypeus semicircularly notched in the middle and posteriorly extending back between the short but widely separated carinae. Maxillary palps 4-segmented. Antennae 12-segmented, with long first and last funicular joints. Gizzard with narrow, separated, anchor-like sepals. Gaster large, its first segment overlying the petiole; anus terminal or subterminal.

Forel's (1905b) definition of Engramma was of the male but was accompanied by the description of the new species (now) Technomyrmex lujae; this is at {original description}.

The genus, as thought in 1922, had been known only since 1910 and comprised six described species. It has a very narrow range, being confined to equatorial Africa and in all probability to the forest regions. Most of the species evidently live in the cavities of myrmecophytes. According to Wheeler, at least one, however, lives in the ground (wolfi) and another, zimmeri subspecies okiavoŽnsis of the Congo, had been found inhabiting "a large pale gray nest, soft, woven and mixed with fine vegetable matter and applied to the trunk of a tree."

The following key is derived from that compiled by Wheeler.

1 Metanotal constriction very deep and long, so that the thorax is halteriform; propodeum with a pair of denticles above Axinidris denticulatum
-- Metanotal constriction only moderately deep, acute; propodeum without denticles 2
2 Body long and slender; head and thorax opaque; antennal scapes extending at least one-fifth their length beyond the occipital border 3
-- Body more thickset; head and thorax shining; antennal scapes shorter 4
3 Scapes surpassing the occiput by one-fifth their length; clypeal notch very large and deep and the median border behind it with a small triangular impression; all the funicular joints twice as long as broad; color black, with brown appendages Technomyrmex andrei as Engramma wolfi
-- Scapes surpassing the occiput by about one-fourth their length; clypeal notch broad and shallow, the median border without an impression; funicular joints shorter; color yellowish red, gaster black, its segments narrowly bordered with yellow Technomyrmex zimmeri
4 Eyes very large, nearly one-third as long as the sides of the head Technomyrmex ilgi
-- Eyes much smaller 5
5 Head, without the mandibles, as broad as long, deeply excavated behind 6
-- Head longer than broad, feebly excavated behind 8
6 Antennal scapes slightly surpassing the occipital border; funicular joints 2 to 7 slightly longer than broad; base of epinotum nearly as long as the declivity, horizontal; pilosity well developed Technomyrmex lujae
-- Antennal scapes not reaching the occipital border; funicular joints 2 to 7 broader than long; base of epinotum much shorter than the declivity, sloping forward; pilosity less abundant 7
7 Brown; length 2.25 to 3 mm Technomyrmex laurenti
-- Dull yellow, with brown gaster; smaller, length 1.8 to 2.2 mm Technomyrmex kohli
8 Antennal scapes reaching the occipital border; funicular joints 2 to 7 broader than long; epinotum evenly rounded, without distinct base and declivity Technomyrmex lujae as Engramma griseopubens
-- Antennal scapes extending about one-sixth their length beyond the occipital border; funicular joints all distinctly longer than broad; epinotum with short base sloping forward and long, flat declivity, sloping backward (from Uganda) Technomyrmex ilgi as Engramma gowdeyi
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© 2001, 2002, 2003, 2004, 2008, 2013 - Brian Taylor CBiol FSB FRES
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