Pseudomyrmex deminutus

The only known collection is from a Tachigali plant in southern Amazonas state, Brazil.

Identification
Ward (1999) - There are no other known species in the sericeus species group in which the queen has such an elongate head (CI ≈ 0.66). The small size, relatively short eyes (for the species group), broad profemur and narrow petiole are also distinctive. In petiole shape P. deminutus is perhaps closest to Pseudomyrmex vinneni but the queens of that species are larger (HW 0.96–1.06) with broader heads (CI 0.77–0.81) and longer eyes (REL 0.60–0.63).

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil.

Castes
Known only from the queen caste.

Nomenclature

 *  deminutus. Pseudomyrmex deminutus Ward, 1999b: 517, figs. 50, 59, 68 (q.) BRAZIL.

Queen
Measurements (n=3). HL 1.19–1.21, HW 0.78, MFC 0.015–0.022, LHT 0.67– 0.68, CI 0.65–0.66, REL 0.58–0.59, REL2 0.89–0.90, FCI 0.02–0.03, FI 0.52–0.53, PLI 0.87–0.88, PWI 0.69–0.72.

A species in the sericeus species group of small stature (HW < 0.80, LHT < 0.70). Palp formula 5,4. Frontal carinae closely contiguous; head elongate, with straight sides and concave posterior margin, in frontal view; eyes relatively short in relation to head length (REL < 0.60); profemur very broad (see FI values). Petiole relatively low, long and narrow, not expanded posterolaterally; petiolar node rounded in lateral view, without differentiated anterior and dorsal faces. Anteroventral petiolar process thin and blunt. Standing pilosity sparse, a pair of long, thin, pale setae on the anterior pronotum, posterior pronotum, mesoscutellum, petiole, and postpetiole. Brownish-black, the antennae, frontoclypeal complex, protibia, and tarsi yellow-brown.

Type Material
Holotype alate queen. BRAZIL Amazonas: Rio Juma, near Apui, 400 km E Humaita, Transamazonica Hwy. [7°08’S, 59°57’W], 30.iv.1985, ex Tachigali, F. Rickson B-41-85. HW 0.78, HL 1.19, EL 0.70, LHT 0.68, PL 0.52, PH 0.45.

Paratypes. Same data as holotype: two alate queens.