Strumigenys semicompta

P.F. Darlington collected the type material in "a in heavy, dense eucalypt forest adjoining rain forest."

Identification
A member of the Strumigenys semicompta-group. For comparative notes see under Strumigenys carnassa.

Distribution based on Regional Taxon Lists
Australasian Region: Australia. Indo-Australian Region: Indonesia, New Guinea.

Nomenclature

 *  semicompta. Codiomyrmex semicomptus Brown, 1959c: 9, fig. 5 (w.) AUSTRALIA. Combination in Glamyromyrmex: Taylor & Brown, D.R. 1985: 64; in Pyramica: Bolton, 1999: 1672; in Strumigenys: Baroni Urbani & De Andrade, 2007: 127. See also: Bolton, 2000: 467.

Worker
Holotype. TL 2.1, HL 0.56, HW 0.42 (CI 75), ML 0.10 (MI 18), WL 0.52, scape L 0.25 mm. Shape of head and mandibles as shown, drawn from a paratype, but slightly wider across occiput. Dorsal surface of cranium strongly convex in the center, sloping to-ward occiput and anteriad (toward clypeus), so that the occipital lobes are narrowly rounded apically as seen from side. Mandibles strongly convex, rising above the anterior clypeal border (as is usual in Codiomyrmex); with five strong, acute conical teeth, the first (nearest base) and fourth a little smaller than the second and third, the apical (fifth) tooth smallest. The basal lamella is normally hidden beneath the clypeus at full closure; it is set at a lower level than the principal teeth and oblique to them, and is separated from them by a brief diastema; in shape and size it resembles the lamella of Strumigenys weberi, but is sharply truncate without being broadened at the apex. Clypeus almost perfectly plane.

Alitrunk narrow, only slightly more than half as wide as the head, its dorsum almost flat from side to side and defined by lateral margins, but forming one gentle convexity from pronotum to propodeal teeth, with only a slight dip at the posterior mesonotum. Seen from above, the pronotum is evenly rounded and marginate, without humeral angles and only slightly wider than the propodeum; promesonotum with a faint median longitudinal carinula. Propodeum curving evenly down into the concave declivity between the dorsolateral margins and the propodeal teeth; teeth with horizontal dorsal borders, completely involved in the broad infradental lamellae, which are briefly concave below the short acute dorsal tips, then below this broadly convex.

Petiole large, its peduncle rapidly enlarging caudad, but distinctly differentiated from the large node. Node high in front, with a strong, bluntly raised anterodorsal margin and steep bicarinate anterior face, the dorsal surface then strongly convex and sloping caudad; node distinctly longer than high, and, seen from above, longer than broad, with rounded sides and truncate anteriorly. Postpetiolar disc broadly subelliptical, broader than long and about 1 1/3 times as broad as petiolar node. A full complement of voluminous, areolate spongiform appendages present in all the usual positions on both nodes and at the base of the gaster. Gaster depressed, much broader than deep. Basigastric costulae distinct, crowded, effaced mesally, extending about 1/5 the length of the first segment.

Gaster otherwise, both nodes, entire alitrunk, most of legs, anterior frontal area of head, and clypeus smooth and shining except for scattered piligerous punctures. Scrobes, upper sides of hind eoxae and petiolar peduncle densely reticulate-punctate. Mandibles, antennae and small parts of legs finely punctulate-granulose, snbopaque to opaque. Cranium, both dorsal and ventral surfaecs, loosely and rather coarsely rugose or costulate, the rugae running more or less longitudinally. Between the rugae are various coarse and fine punctures, rendering the surface here opaque (more shining near the midline).

Occiput and rest of dorsal surfaces of body, including the entire legs, with numerous long (mostly 0.07-0.10 mm.) fine hairs with tapered or truncate tips, becoming more spatulate on center of head, and on anterior half of head proper represented by shorter, appressed linear-spatulate hairs directed mesad, this appressed pilosity repeated in miniature on clypeus. Scapes each with a row of short remiform hairs, inclined apicad. Mandibles, antennae, gula, and tarsi with fine reclinate hairs.

Color deep reddish-brown, head and gaster darkest; clypeus, mandibles, antennae and legs yellowish-ferruginous.

Bolton (2000) - TL 2.0-2.1, HL 0.54-0.62, HW 0.40-0.44, CI 71-76, ML 0.09-0.12, MI 16-19, SL 0.23-0.27, SI 56-62, PW 0.23-0.26, AL 0.54-0.58 (10 measured).

Type Material
Holotype a worker, chosen from a series of 18 workers taken together in heavy, dense eucalypt forest adjoining rain forest at Shipton's Flat, about 20-25 miles south of Cooktown, Queensland, Australia (P. F. Darlington leg.). The 17 paratypes are very similar to the holotype, and vary hardly at all in measurements; several are subtencral: these will be placed in the MCZ and with other ant collections.

Bolton (2000) - Holotype worker and paratype workers, AUSTRALIA: Queensland, Shipton's Flat, about 20-25 miles south of Cooktown, vi.1958 (P. F. Darlington) [examined].



References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
 * CSIRO Collection
 * 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.
 * Taylor R. W., and D. R. Brown. 1985. Formicoidea. Zoological Catalogue of Australia 2: 1-149.