Megalomyrmex pusillus

Nothing is known about the biology of .

Identification
Brandão (1990) - Forel (1912) observed a wide deep brown transversal band at the first gaster segment, contrasting with the light-yellow body. This condition is not constant for most samples, but it is present in the three available dealated females. I noticed intraspecific variation among workers in terms of color, presence of median seta at the clypeal set, degree of development of the anteromedian clypeal denticle and propodeum shape. The sample from Alto da Serra, SP, Brasil (types and non-types) have extreme values for all measured characters, as already noticed by Borgmeier (1939).

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Mexico.

Biology
Brandão (2003) - Of this rather rarely collected, although very distinctive species, I received from a worker collected in Poços de Caldas, Minas Gerais state, Brazil (21°48’S, 46°34’W), in October 28, 1991, by A.M.D. Aguiar. This is the first record of this species in Minas Gerais.

Castes
Known only from the worker caste.

Nomenclature

 *  pusillus. Megalomyrmex pusillus Forel, 1912g: 15 (w.) BRAZIL. Brandão, 1990: 453 (q.).

Worker
Brandão (1990) - Smooth mandibles with dental formula (1-2) + 4; anterior border of clypeus in general round with median denticle; frontal suture not impressed; occipital margin not raised: promesonotal suture when present faintly impressed at dorsum; dorsal face and declivity of propodeum meeting in lateral acute tubercles divergent at apex and laterally compressed: declivity smooth; epipetiolar carina not complete dorsally; ventral face of postpetiole with anterior denticle; postpetiole ventral face without process.

Pilosity: long erect or suberect hairs (exceeding compound eyes diameter) at body dorsum and smaller subdecumbert hairs at clypeus, antennae and legs.

Color: bright light yellow.

Queen
Brandão (1990) - Differs from conspecific workers in the following characters: triangular head in frontal view with areas of striation at the antenna! sockets and distal portion of lateral area of clypeus. Ocelli equally developed. Median propodeal depression deeper than in workers. Postpetiolar node distinctly broader than petiolar node.

Type Material
Brandão (1990) - Alto da Serra, SP, Brasil (23°47'S, 46°19'W). Lectotype designation: Lectotype and 1 paralectotype at the Museum de la Ville de Geneve; 1 paralectotype at Naturhistorisches Museum. Basel.