Calyptomyrmex caledonicus

This is the only species of Calyptomyrmex known from New Caledonia. It is most frequently found in leaf litter samples from rainforest sites.

Identification
Hairs on head and body thin (essentially the same width along entire length, or only slightly and gradually expanded distally, and with blunt tips), propodeum armed with short, triangular spines, mesonotum and dorsal face of propodeum forming a single, continuous surface (the mesonotum and propodeum uniformly curved). This is the only species from the Oceania region with a uniformly curved mesosomal dorsum.

Distribution
This taxon was described from New Caledonia.

Nomenclature
Holotype worker and 1 worker paratype from Foret de Thy, New Caledonia, 21 May 1984, G. Monteith & D. Cook, rainforest, litter (, holotype ANIC32-05 1668, paratype ANIC32-053399).

Description
Worker description. Mandibles delicately striate basally, essentially smooth apically. Eyes small, with 2–3 ommatidia in greatest diameter. Propodeum in lateral view armed with short, thin spines. Propodeal lobes essentially uniform in thickness. Node of petiole in profile cubic or box-like and higher than that of postpetiole, both approximately the same volume. In dorsal view the petiolar node narrower than the postpetiolar node. Head indistinctly rugose, the rugae tending to be longitudinal anteriorly and forming a weak network posteriorly, with the entire surface finely but distinctly punctate, the punctations partially obscuring individual rugae. Mesosoma and petiolar and postpetiolar nodes rugose superimposed over an indistinctly punctate background, the individual rugae wavy and sometimes forming a network, otherwise more or less linear. Gaster finely and indistinctly sculptured. Hairs erect, uniform in diameter or slightly swollen medially or distally, generally with sharply pointed tips. Clypeal fork with enlarged and thin hairs which are approximately the same length. Colour yellow-red, antennae and legs slightly lighter.

Measurements. Worker (n = 12) - CFW 0.10–0.14; CI 88–94; HL 0.68–0.80; HW 0.62–0.76; ML 0.63–0.79; MTL 0.28–0.35; PetI 110–133; PetL 0.16–0.21; PetW 0.21–0.26; PronW 0.42–0.52; SI 57–65; SL 0.38–0.45.

Morphologically, the available material is fairly uniform although it does show moderate variation in size. However, this size variation is continuous with no indication of distinct subsets and this variation is interpreted as intraspecific.