Myopias densesticta

The holotype and other workers were found in savannah woodland grading into riparian rain forest (gallery forest), at an elevation of about 300 m. A Kuranda queen is from a similar elevation. A pin of three workers comes from Koombooloomba, near the dam of the same name south of Ravenshoe, Queensland, at about 750 m in rain forest.

Identification
Willey and Brown (1983) - Worker and queen: A member of the M. tenuis group, similar to Myopias chapmani, but with much more distinct and abundant foveolate sculpture and a shorter, wider median clypeal lobe and shorter antennae. Also, the trunk is not deeply divided at the metanotal groove, the petiolar node is more massive, and the gaster is gently tapered, not sharply constricted, behind the first segment.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  densesticta. Myopias densesticta Willey & Brown, 1983: 268, figs. 11, 29 (w.q.) AUSTRALIA.

Worker
Holotype: TL 5.6, HL 1.03, HW 0.97 (CI 94), ML 0.55 (MI 53), MLO 0.82, SL 0.85 (SI 88), EL 0.09, WL 1.62, hind femur L 0.87, hind tibia L 0.83 mm.

Worker, paratypes (n = 3 of 9 from two colonies, including largest and smallest, the holotype): TL 5.6-5.7, HL 1.03-1.07, HW 0.97-1.03 (CI 94-97), ML 0.55-0.56 (MI 51-54), MLO 0.82-0.83, SL 0.85-0.86 (SI 83-88), EL 0.09-0.11, WL 1.62-\.71, hind femur L 0.87-0.89, hind tibia L 0.83-0.84 mm.

In overall size, proportions of head, and mandibles, this species is very similar to Myopias chapmani, but the sides of the head are a trifle more convex, and the basal angle of the mandible is a little less distinct; also the following, more definite differences from M. chapmani:

(1) Antennae shorter; scapes overreach posterior border when held straight back by only a slight amount, less than their apical width. Segments II through VIII of funiculus wider than long; I (pedicel) more than twice as long as II.

(2) Median clypeal lobe shorter, wider (CLL 0.08-0.10, CLW 0.16-0.17 mm), with sharply angular free corners terminating the divergent carinae that form the lateral edges of the lobe.

(3) Promesonotum shorter than propodeum; propodeal dorsum about twice as long as mesonotum, and nearly on the same level; both only weakly convex and meeting at a distinct but not deeply impressed metanotal groove, so that the side-view dorsal profile is a nearly smooth, gently convex outline from top of front pronotal incline to top of propodeal declivity.

(4) Petiolar node more massive and more nearly cuboidal, less notably longer than high; seen from above wider than long, but sides convex; widest near mid length.

(5) Second gastric (true abdominal IV) segment narrower and lower than first segment (postpetiole), so that the gaster is gradually tapered caudad of I, and not constricted and recovering after.

(6) Body, especially head, trunk and petiolar node, with deeper and much more distinctly developed foveolate sculpture, the punctures mostly 0.01-0.02 mm in diameter and densely crowded, contiguous on front of head between eyes and frontal lobes, becoming larger, mostly 0.02-0.03 mm in diameter and narrowly separated on posterior half of head, at times with intervening, indistinct, longitudinal strigulosity, and still coarser and more widely spaced on sides and underside of head and near median frontal sulcus (which reaches back to near the posterior quarter of HL). Trunk and petiole with abundant foveolae, mostly 0.02-0.04 mm in diameter, separated on the average by a little more than their own diameters, but more crowded and more elongate on sublateral strips of propodeal dorsum; truncal midline strip partly open, with few foveolae. In general, interfoveolar surfaces smooth and shining, but lower sides of propodeum indistinctly, longitudinally costulate, and sides of petiolar node coarsely and densely foveolate and minutely roughened, more or less opaque. Gaster I smooth, with scattered coarse punctures, and these become fewer and smaller still on gaster II. Mandibles smooth and shining, with scattered punctures. Antennal scapes and legs smooth and shining, but with fine punctulation. Propodeal declivity nearly smooth, but peppered with many small foveolae. Clypeus smooth and shining.

(7) Pilosity and pubescence more abundant than in M. chapmani, most notably on mandibles and antennal scapes; decumbent pubescence on head more conspicuous, directed mesad.

(8) Color perhaps averaging slightly darker than in M. chapmani, but legs and antennae tending to be lighter, more yellowish red. As in chapmani, the palpi are segmented 3,3, and upturned teeth are present, one on each labral lobe. Worker variation is very slight overall. The Koombooloomba series averages very slightly larger, and the compound eyes may be a trifle larger than in the Shipton's Flat colony.

Queen
Dealate, a unique taken in rotten wood in a rain forest patch near Kuranda, Queensland, 31 October 1950, leg. Brown: TL 6.7, HL 1.07, HW 1.05 (CI 98), ML 0.52 (MI 49), MLO 0.81, SL 0.85 (SI 81), EL 0.24, WL 1.92 mm.

Type Material
Holotype [MCZ] one of six workers from Shipton's Flat, south of Cooktown, Queensland, during June 1958, leg. P. F. and P. J. Darlington. This locality is savannah woodland grading into riparian rain forest (gallery forest), and lies at an elevation of about 300 m. (The Kuranda queen is from a similar elevation.) A pin of three workers comes from Koombooloomba, near the dam of the same name south of Ravenshoe, Queensland, at about 750 m in rain forest, “4/7/71,” leg. Taylor and J. Feehan. We have no information about possible prey.



Etymology
The name densesticta refers to the characteristic foveolate sculpture.

References based on Global Ant Biodiversity Informatics

 * Willey R. B.; W. L., Jr Brown. 1983. New species of the ant genus Myopias (Hymenoptera: Formicidae: Ponerinae). Psyche (Cambridge) 90: 249-285.