Simopelta longirostris

Both type specimens were collected from a Winkler extraction. A series from Ecuador formed a column on the forest floor.

Identification
Mackay and Mackay (2008) - The worker of this species is easily recognized by the narrow lobe of the clypeus, which overhangs the remainder of the clypeus. The transverse striae on the head, as well as the relatively short antennal scapes and the short mesonotum could cause confusion with Simopelta breviscapa, but the latter species has a broadly rounded medial clypeal border or at the most a slightly angulate point. The long, lobed process over the clypeal apron could cause confusion with Simopelta andersoni. They can be easily separated as S. andersoni has four mandibular teeth, S. longirostris has three.

Key to Simopelta

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia, Ecuador.

Habitat
High elevation tropical cloud forest (1840m).

Castes
Known only from the worker caste.

Nomenclature

 *  longirostris. Simopelta longirostris Mackay & Mackay, 2008: 308, figs. 14, 40 (w.) COLOMBIA.

Worker
The worker is a small (total length 3.0-3.5 mm), black ant, with brownish legs. The head is relatively elongated, the head length is 0.82 mm, the head width 0.58 mm. The mandibles have three, well-developed, sharp teeth. The clypeus forms an extended, narrow lobe which passes over the apron of the clypeus. The sides of the head are nearly parallel, only slightly narrowed anterior to, and posterior to the eye. The posterior border of the head is broadly convex. The eye is small (maximum diameter 0.06 mm) located more than 2 diameters from the anterior margin of the head. The scape is relatively short (0.74-0.78 mm) and extends only slightly past the posterior lateral corner of the head. The mesonotum (length 0.28 mm) is noticeably shorter than the dorsal face of the propodeum (length 0.42 mm), when both are viewed in profile. The anterior and posterior faces of the petiole are parallel; the dorsal face is well developed and slopes upwards. The spiracular horns and the subpetiolar process are weakly developed.

Short (0.04 mm) erect and suberect hairs are present on most surfaces, including the dorsal and ventral surfaces of the head, the scapes, dorsum of the mesosoma, legs, dorsum of the petiole, and dorsum of the gaster. Longer hairs (up to 0.1 mm in length) are present on the mandibles, clypeus, and ventral surface of the gaster. A few scattered hairs are nearly appressed.

The mandibles are dull and finely striated, the dorsum of the head is covered with transverse striae, which pass anteriorly on the sides of the head and are mostly transverse on the ventral surface of the head. The striae on the mesosoma are similar, although portions are smooth and glossy, including the lower one third of the pronotum, lower half of the mesopleuron, and most of the legs. The side and dorsum of the petiole and postpetiole (with tiny, scattered punctures) are finely striated and partially smooth and glossy.

Type Material
Holotype worker (# 50123 ), one paratype worker (# 50122 ), COLOMBIA Nariño R.N. La Planada Vía Hondón, 1°15’N 78°15’W 1930m, Winkler 16-20.xii.2000, G. Olivia Leg. M.1446.

Etymology
From Latin longis meaning long, and rostrum, meaning beak, referring to the long clypeal process which overhangs the apron of the clypeus.