Myrmecina gymnocephala

Nothing is known about the biology of .

Identification
Okido, Ogata, and Hosoishi (2020) - A member of the Myrmecina macrops complex (Myrmecina breviata, M. gymnocephala, Myrmecina macrops and Myrmecina nitidiuscula). This species is distinguished within its complex in having developed propodeal spines, and the pronotum and mesonotum with straight rugae. The dorsal surface of the mesosoma of the workers distributed in Seram is sculptured only on the lateral portion, while that of the workers distributed in Mindoro is sculptured on the entire surface.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia, Philippines.

Nomenclature

 * . Myrmecina gymnocephala Okido, Ogata & Hosoishsi, 2020: 49, fig. 21 (w.) INDONESIA.

Worker
Holotype. TL 2.78, HL 0.67, HW 0.66, CI 99, SL 0.62, SI 93, PW 0.43, ML 0.74. Paratype. TL 2.71-2.93, HL 0.66-0.67, HW 0.66-0.68, CI 100-104, SL 0.61-0.63, SI 90-93, PW 0.42-0.45, ML 0.70-0.80 (5 measured)

Head subrectangular, as long as broad in full-face view; median portion of occipital margin flattened or slightly concave; occipital corners widely rounded, not projected posteriorly. Masticatory margin of mandible bent at midlength (third small tooth or sixth tooth); apical tooth strong, third tooth robust, followed by 4-5 small teeth and a stout basal tooth bearing blunt apex; small teeth frequently unclear. Dorsal surface of clypeus slightly concave; median portion of anterior margin weakly projected with a median process but the process frequently unclear; lateral portion simple, lacking sharp ridge in front of antennal insertions. Anterior dorsal surface of labrum with paired small denticles distinctly, closed to each other. Frontal carinae present but variable in length; running back to or beyond the level of the posterior margin of the eyes. Eyes extremely large and convex, varying in size with maximum diameter 0.14-0.16 mm and 7-8 ommatidia; malar space as long as diameter of eye in profile. Antennal scape long, extending beyond posterolateral corner of head distinctly; antennal flange weakly developed.

Dorsal outline of mesosoma slightly convex in profile. Pronotum without denticles; anterior ventrolateral portion not angulate. Eumetanotal spine absent. Propodeal spine triangular and very small, not reaching vertical posteriormost limit of propodeum in profile. Propodeal lobe slightly raised. Propodeal spiracle large, situated near base of propodeal spine, distance between posterior margin of spiracle and posterior margin of propodeum slightly longer than diameter of spiracle. Petiole long, longer than high in profile, and longer than broad in dorsal view; small but distinct dorsal crest located almost at midlength in profile; subpetiolar process absent or unclear; ventral outline flattened or slightly convex. Postpetiole broader than petiole in dorsal view; anterolateral margin rounded; dorsal outline slightly convex or flattened in profile; ventral outline projected rectangularly at anterior and posterior portion.

Anterior margin of gaster not concave in dorsal view.

Head smooth and shining, completely absent any sculpture except for frontal carinae and a few rugae in front of eyes; ventrolateral portion smooth and shining. Mandibles smooth and shining, frequently with yellow spots on dorsal surface. Clypeus smooth and shining. Mesosoma with with longitudinal rugae which are thick, sometimes median portion smooth and shining in dorsal view. Petiole and postpetiole with weak rugae. Head with sparse pilosity on dorsum. Mesosoma with sparse pilosity on dorsum. Pilosity of pronotum slightly shorter than maximum diameter of eye. Pilosity of petiole and postpetiole as long as that of mesosoma. Petiole without hairs on ventral surface. Postpetiole with about 4 hairs on ventral surface. Head, mesosoma, petiole and postpetiole reddish brown.