Dorymyrmex amazonicus

The type series was collected in the vicinity of an Amazonian forest relict, outside Leticia (Colombia). All the specimens were collected in open deforested habitat, probably this is an indication of the preference of this species to nest in highly anthropic or disturbed environments. (Cuezzo and Guerrero 2011)

Identification
Cuezzo and Guerrero (2011) - Worker. Large ant, TLI: 133–135. Head with lateral margins broadly convex and posterior margin of head concave medially. Short scape not surpassing the posterior margin of the head more than three times its apical width.

At first view, this species could be confused with Dorymyrmex brunneus, but a greater TLI, shorter scapes, eyes placed deep inside the head capsule, and a continuous mesosomal profile in D. amazonicus are the best characters to separate it from D. brunneus. Other Dorymyrmex species found in Colombia share with D. amazonicus the shape of mesonotal profile (i.e., D. pyramicus), but all the characters, given in the key and in the diagnosis above, are useful to separate D. amazonicus from other species of Dorymyrmex found in Colombia.

Distribution
Known only from the type collection - Amazonas, Colombia.

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia.

Castes
Known only from the worker caste.

Nomenclature

 *  amazonicus. Dorymyrmex amazonicus Cuezzo & Guerrero, 2011: 5, figs. 1a-c, 13 (w) COLOMBIA.

Worker
Holotype (Paratypes = 2). HL: 1.00 (1.02–1.04). HW: 0.92 (0.94–0.96). EL: 0.30 (0.28–0.30). EW: 0.22 (0.22). SL: 1.06 (1.06–1.08). WL: 1.32 (1.36–1.40). CI: 92 (92). SI: 106 (104). REL: 30 (27–29). OI: 73 (73–79). TLI: 132 (133–135).

Head and scapes reddish-brown; lateral clypeal region and dorsal face of mandibles testaceous yellow; masticatory mandibular margin dark brown; mesosoma, legs, petiole, and gaster yellowish-brown. Whitish, short, and appressed pubescence covering all the body tagma. Head: head slightly longer than wide, with lateral margins strongly convex and posterolateral corners rounded. Posterior margin of the head concave in the middle. Mandibles strongly striate, with apical tooth four times longer than others. Masticatory margin with four denticles. Compound eye well developed and placed far inside the head capsule. Psammophore with short hairs disposed in a semicircle; the hairs on the top line are close to the foramen magnum and not reaching the oral cavity. Scape short (SI = 104–106) not surpassing the posterior margin of the head more than three times its apical width. Mesosoma: dorsal face of pronotum with no erected setae, pronotum and mesonotum in profile forming a continuous line, not interrupted, metanotal suture not impressed. Dorsum of propodeum weakly sinuate. Propodeal cone acute, upward directed with wide base. Apical point of the propodeal cone reaches the same level of the highest point of pro-mesonotum in lateral view. Declivitous face of propodeum convex. Metasoma: petiolar scale wide, thin and rounded in the apex.

Type Material
Holotype. Amazonas, Leticia,, 06 Jun 1976,Columbia. Paratypes: 2w, Amazonas, Leticia,, 06 Jun 1976, COLOMBIA: 1w , 1w (IFML).

Etymology
The name amazonicus refers to the apparently unusual distribution of this species, the Amazon rainforest in Colombia. It is a noun in apposition and invariant.