Myopias gigas

Because of the long mandibles and large size, we guess that Myopias gigas may be a millipede predator, but we have no direct evidence of feeding behavior for this species. This magnificent species is even larger than M. loriai, and has very different sculpture, but the two forms are obviously closely related. (Willey and Brown 1983)

Identification
Willey and Brown (1983) - Worker: A very large species of the Myopias loriai group, even larger than M. loriai with proportionately longer mesonotum and petiolar node, and with the head dorsally, trunk dorsum and pleura of posterior section of trunk sharply and regularly striate; body otherwise prevailingly smooth and shining. Funicular segment II very long, longer than I.

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

Nomenclature

 *  gigas. Myopias gigas Willey & Brown, 1983: 251, figs. 1, 12 (w.) NEW GUINEA.

Worker
Holotype: TL 16.9, HL 2.50, HW 2.60 (CI 104), ML 2.26 (MI 90), SL 2.62 (SI 101), EL 0.45, WL 4.61, petiole L 1.7, hind femur L 3.7, hind tibia L 3.16 mm.

This, the largest known species of Myopias, has the broad, posteriorly narrowed head of the loriai group; long, slender, curved mandibles and rather large eyes with many fine facets. A scape, when held straight back as seen in full-face view, surpasses the posterior border of the head by nearly 2 1/2 times the apical scape width. The posterior border of the head is transverse and nearly straight, varying from very feebly concave to subsinuate in slightly different views. As in M. loriai, the median clypeal lobe is apically biconvex, with a shallow median notch; the lobe is shorter and broader than in M. loriai, and tapers slightly from base to apex. Antennal funicular segment II is longer than I, III and all other funicular segments except the apical, and it is 2.5 times longer than its maximum (apical) width. No differentiated antennal club.

Labrum with a sharp erect tooth at the apex of each labral lobe; no median labral tubercle. Palpi concealed, not seen. Mandibles as shown in Figure I; apical tooth followed closely basad by 2 coarse denticles and a blunt tooth; middle tooth followed basad by a low, rounded basal angle. Strix (mandibular groove) well-developed from base to apex.

Trunk long and robust; mesonotum longer than in lorioi, but wider than long (L/W ~ 0.7). Metanotum present as a deeply impressed groove, widening laterad on each end. In side view profile, pronotum strongly convex, although transversely impressed just in front of the raised, cariniform posterodorsal margin; mesonotum feebly convex and sloping downward behind, but its anterior margin raised slightly above the posterior pronotal margin, especially (as in the type) when the two somites are flexed against each other. Promesonotum (without cervix) and propodeum subequal in length; propodeum broadly convex from front to rear, with its declivity steeper than its dorsum, but passing into dorsum through a gentle curve. Mesopleural suture distinct and complete, moderately deeply impressed (more distinct than in M. lorioi). Propodeal spiracle elongate and oblique, its opening about 2 ½ times longer than wide.

Petiole loaf-shaped, longer than broad and longer than high; exact shape of subpetiolar process, if any, not determined because the extreme anterior end of the segment is hidden by the coxae. Gaster long, gently down-curved, with a distinct constriction between first and second segments; dorsally viewed, second segments longer and a little wider than first. Sting long and strong, distinctly upcurved.

Dorsum of head completely finely and regularly striate in a longitudinal direction, the striae mesal to and behind the eyes tending to curve slightly outward. Dorsum and declivity of trunk similarly striate, but in a transverse direction, arching on pronotum. Sides of trunk behind pronotum with similar, oblique striation, continued from the propodeal dorsum through a curve. Remainder of head, body and appendages smooth and shining, including mandibles, cervical border of vertex and sides of pronotum. Coarse, spaced, piligerous punctures are conspicuous in smooth areas, particularly the sides of the head, mandibles, femora and tibiae, petiole, and normally exposed surfaces of gastric terga.

Pubescence appressed and decumbent, generally very sparse, except on antennal flagella, coxae, tarsi, flexor surfaces of fore tibiae, flexor surfaces of mid femora, extensor surfaces of mid tibiae, and apex of hypopygium. Rather abundant erect or suberect, fine, tapered hairs, from short to over 0.5 mm long, occur on almost all normally exposed surfaces of body and appendages. Color deep reddish brown, appendages mainly clear light red.

Type Material
Holotype a unique worker from Dobodura, Papua New Guinea (P. J. Darlington leg.).

References based on Global Ant Biodiversity Informatics

 * Janda M., G. D. Alpert, M. L. Borowiec, E. P. Economo, P. Klimes, E. Sarnat, and S. O. Shattuck. 2011. Cheklist of ants described and recorded from New Guinea and associated islands. Available on http://www.newguineants.org/. Accessed on 24th Feb. 2011.
 * Willey R. B.; W. L., Jr Brown. 1983. New species of the ant genus Myopias (Hymenoptera: Formicidae: Ponerinae). Psyche (Cambridge) 90: 249-285.
 * Wilson Edward O. 1959. Adaptive Shift and Dispersal in a Tropical Ant Fauna. Evolution 13(1): 122-144