Cardiocondyla micropila

This species is only known from west of the Wallace Line and widely distributed and abundant over Indochina, Malaysia and the Philippines from sea level up to 1000 m. In contrast to Cardiocondyla latifrons it is so far not known from Java and Sulawesi and is much less abundant than the latter species in Thailand. Habitat selection, overall abundance and social structure correspond to the situation in C. latifrons. Queen-queen aggression, male behavior and morphology are also similar. According to the data of Frohschammer, the number of queens in the polygynous nests is higher than in Cardiocondyla latifrons. (Seifert, 2022)

Identification
Worker (Figure 14, Table 2): Very small, CS 395 µm. Head shorter than in C. latifrons (CL/CW 1.120), with notably concave occipital margin. Postocular distance relatively small, PoOc/CL 0.423. Scape short SL/CS 0.826. Eye rather small, EYE/CS 0.232. In position with CL in visual plane, anterior clypeal margin between the level of frontal carinae strongly concave and not forming a sharp edge; instead this concavity appears in frontal view as a small area, the lower margin of which is marked by the three clypeal macrosetae. In dorsal view, the lower margin is usually concealed under the upper margin that is the anterior reference point to measure CL. Occipital margin notably concave. Frontal carinae very widely separated (FRS/CS 0.331) and almost parallel immediately posterior of the FRS level. Dorsal mesosomal profile strongly convexly vaulted but with a contrasting small plateau on anterior pronotal dorsum. Pronotal corners in dorsal view weak. Spines very long (SP/CS 0.397), in dorsal view slightly diverging, in lateral view straight or slightly downcurved, their axis deviating by 30–35° from longitudinal axis of mesosoma. Petiole rather wide (PeW/CS 0.310), its node in dorsal view as long or slightly longer than wide, narrowing frontad. Petiole in lateral view with a short peduncle and a convex dorsal node profile that steeply slopes down to the caudal cylinder and high (PeH/CS 0.362). Postpetiole in dorsal view wider than in C. latifrons (PpW/CS 0.460) and with a concave anterior margin; in lateral view higher than in C. latifrons (PpH/CS 0.326), its sternite with pronounced anterolateral corners that are formed by bilateral lobes which strongly protrude compared to anteromedian level. Whole dorsum of head and mesosoma foveolate-reticulate, thus appearing at lower magnifications perfectly matt. Vertex, with deep foveolae of 15–20 µm diameter which often show an inner structure reminiscent of a three- or four-leafed cloverleaf (Figure 14D); such foveolae are on mesosoma restricted to pronotum and dorsal mesonotum, the foveolae on remaining mesosoma and waist are smaller and usually without cloverleaf-structure. Postpetiole less strongly sculptured, frequently rather shiny. First gaster tergite smooth and shiny and with a delicate microreticulum. Pubescence on 1st gaster tergite much shorter than in C. latifrons (PLG/CS 3.18, sqPDG 6.28). All body parts concolorous light yellowish or orange.

See Cardiocondyla latifrons for separation from this otherwise similar species.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Malaysia.

Nomenclature

 * . Cardiocondyla micropila Seifert, 2022: 45, fig. 14 (w.) MALAYSIA.

Type Material
Holotype worker (on separate pin) and 3 paratype workers labelled “MAL: 2.7825° N, 104.1309° E, Tioman, Gunung Kajang, 200 m, Primärwald, in Stein, Frohschammer 2007.06.06-118”, depository SMN Görlitz; 3 paratype workers labelled “MAL: 2.7786° N, 104.1278° E, Tioman, Primärwald, in Stein, Frohschammer 2007.06.03-99”, depository SMN Görlitz.

Taxonomic Notes
Following an earlier provisional naming in the author’s data files, this species has been named by other authors in two non-taxonomic, sociobiological papers as “Cardiocondyla microseta” (Oettler et al., 2010; Schmidt & Heinze, 2018). According to the provisions of ICZN, this name was not made available with these publications. This provisional naming was later changed by me to “micropila” because “microseta” would have meant “small strong hairs” or “small bristles” which is not adequate. A return to “microseta” would also mean the expense of changing specimen labels in two remotely-housed collections.