Simopelta mayri

Known only from the holotype worker; collected by hand in tropical rain forest, 1430 m.

Identification
Mackay and Mackay (2008) - The four mandibular teeth, and the spine on the medial anterior clypeal border, would separate this species from most of the others in the genus. It could be confused with Simopelta laticeps, from which it differs in having the posterior edge of the head nearly straight, where it is strongly concave, and forms sharp, posterior lateral lobes in S. laticeps. Additionally, the petiole is relatively narrow (width at the base of the peduncles, including the poorly developed spiracular horn 0.30 mm, height at the same level 0.32 mm).

This species differs from Simopelta curvata, in having moderately well-developed, transverse striae on the posterior half of the head, which bends anteriorly towards the eyes on the sides of the head. Additionally, the region on both sides of the tooth of the clypeus is noticeably concave.

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia.

Castes
Known only from the worker caste.

Nomenclature

 *  mayri. Simopelta mayri Mackay & Mackay, 2008: 311, figs. 43, 44 (w.) COLOMBIA.

Worker
The worker is a moderate sized (total length 4.5 mm), reddish brown specimen. The mandible has four well-developed teeth, the anterior medial border of the clypeus has a single, short (0.05 mm) sharp tooth, with the area adjacent to the tooth being distinctly concave. The head length is 1.11 mm (excluding the clypeal tooth), the head width is 1.03 mm. The eye is small (maximum diameter 0.04 mm, and the scape (1.04 mm) extends past the posterior lateral corner of the head. The mesosoma is depressed at the metanotal suture, the petiole is relatively narrow when viewed in profile, with the anterior and posterior faces being nearly parallel, and forming a broadly rounded apex. The subpetiolar process is a single, narrow flange, which is slightly angulate posteriorly.

The mandibles are coarsely striated, the head is mostly punctate, but fine, transverse striae may be present, especially posteriorly. Transverse striae are present on all surfaces (top and side) of the mesosoma, including the propodeum. The petiole has poorly defined, horizontal striae on all surfaces. The dorsum of the postpetiolar is smooth and glossy, with only fine sculpture.

Erect and suberect hairs are present on all surfaces, including the dorsal and ventral surfaces of the head, the scapes, the mesosoma, the legs, the petiole, and the gaster. Hairs tend to be of two distinct lengths, the longest are about 0.3 mm in length, and are sparse, the other hairs are much more abundant, and about 0.04 mm in length.

Type Material
Holotype worker (50084, ), COLOMBIA: Nariño, Mun. Orito, Territorio Kofán Bosque, 0°30’7”N 77°13’43”W, 1430m, Cap. Manual, 1-4 25.ix.1998 E. González, Leg.

Etymology
Named in honor of Ernst Mayr, one of the most prominent biologists of our time, who recently died at 100 years of age. Dr. Mayr generously supported our research at the Museum of Comparative Zoology.