Cataulacus hispidulus

Specimens have been collected on vegetation in rainforest.

Identification
A member of the granulatus group. Of the species immediately related to Cataulacus granulatus, Cataulacus hispidulus is the most easily distinguished. The shape of the petiole and its ventral process is distinctive and will effectively separate the species from all others in the Indo-Australian and Oriental regions, but the general body form of the worker renders it very easily identifiable when one is acquainted with the genus. The short, stocky build of the body, sharp rugoreticulum with shining interspaces and the abundant hairs form an easily recognizable combination of characters, not seen in any other ally of granulatus. (Bolton 1974)

Regional Cataulacus Key

Distribution
Known from Brunei Darussalam, Indonesia (Sumatra) and Malaysia (Sabah).

This taxon was described from Indonesia (Sumatra).

Genetics
Polymorphic microsatellites have been identified for this species. (Debout et al. 2002)

Nomenclature

 *  hispidulus. Cataulacus hispidulus Smith, F. 1865: 76, pl. 4, fig. 7 (w.) INDONESIA (Sumatra). Bolton, 1974a: 66 (q.m.). Subspecies of granulatus: Dalla Torre, 1893: 138; Emery, 1924d: 298. Revived status as species: Donisthorpe, 1932c: 474. Senior synonym of brookei: Bolton, 1974a: 66.
 * brookei. Cataulacus brookei Forel, 1901e: 378 (w.q.m.) BORNEO. Junior synonym of hispidulus: Bolton, 1974a: 66.

Worker
Bolton (1974) - TL 4.6 – 5.8, HL 1.10 – 1.30, HW 1.31 – 1.50, CI 112 - 123, EL 0.40 – 0.48, OI 30 - 34, SL 0.64 – 0.72, SI 46 - 48, PW 1.14 – 1.25, AL l.14 – 1.22, MTL ca 0.70 (6 measured).

Occipital crest incomplete medially, the vertex rounding into the occiput. Occipital corners with a relatively large tooth followed by three or four smaller denticles along the occipital crest on each side. Sides of head behind eyes strongly denticulate. Edges of frontal carinae usually jagged, often more strongly so on the posterior than the anterior half, which in some cases is virtually smooth. Alitrunk with a massive appearance in dorsal view, short and broad, with the pronotal margins strongly denticulate. Propodeal spines narrow and short, each one less than half the length of the distance separating it from its twin. Petiole short and low in profile, the anterior face sloping gently into the very weakly convex dorsal surface. The latter curves posteriorly to the junction with the postpetiole, there being no distinct free posterior face to the petiole. Subpetiolar process large and complex, anteroventrally with a bluntly rounded angle or tooth and posteroventrally with a long, posteriorly directed spur. First gastral tergite short, broad, convex, not marginate laterally.

Sculpturation of dorsum of head and alitrunk a rather coarse and well-defined rugoreticulum, the interspaces of which are feebly reticulate-punctate and shining. First gastral tergite sculptured as alitrunk but the rugoreticulum much finer and the puncturation of the interspaces more distinct. Propodeal declivity finely and densely reticulate-punctate. All dorsal surfaces of head, body and appendages with abundant thick, blunt hairs, yellowish or white in colour and very distinct. On the head and alitrunk the hairs tend to arise from the points of intersection of the meshes of the reticulum.

Queen
Bolton (1974) - TL 7.2, HL 1.56, HW 1.66, CI 106, EL 0.50, OI 30, IOD 1.34, SL 0.74, SI 44, PW 1.54, AL 1.97, MTL 0.94.

As worker but denticulation of sides of head reduced to small, blunt tubercles. Propodeal spines shorter than in worker but still distinct. Subpetiolar process with the posteroventral spur more strongly developed, very long and conspicuous. First gastral tergite much longer than broad, length ca 2.40, width ca 1.70. Sculpturation of head and pronotum as worker with a similar arrangement of short, blunt hairs, but the interspaces of the rugoreticulum are less shiny and have  a granular appearance. Mesoscutum and scutellum coarsely longitudinally rugose with a few transverse meshes, many of which are incomplete. First gastral tergite with an extremely fine rugoreticulum, coarsest basally, and a dense reticulate-puncturation. In the centre of the sclerite is a short, longitudinal strip which is virtually devoid of sculpturation and contrasts with the surrounding areas.

Male
Bolton (1974) - The head of the male examined (syntype of brookei) is missing. PW 0.92, A: 1.64, MTL 1.75.

Notauli well developed, the anterior arms with some distinct cross-ribs. Limits of the posterior arm poorly defined laterally, the groove distinct and broad. Parapsidal furrows absent or almost completely masked by the sculpturation, visible on one side as a slightly more shining strip in the syntype of brookei. Propodeal spines reduced to a pair of minute but acute teeth. Subpetiolar process short and blunt, without the posteroventral spur characteristic of the worker and female castes. Sculpturation of alitrunk a fine rugoreticulum, coarsest on the pronotum, the interspaces reticulate-punctate. Pedicel similarly sculptured but gaster with only a very fine, superficial reticulate-puncturation. Abundant short, thick white hairs present as in the other castes. Exposed portion of parameres smooth and shining, unsculptured apart from the pits from which hairs arise, strongly arcuate in ventral view.

Type Material
Bolton (1974):

Holotype worker, SUMATRA (A. R. Wallace) (UM, Oxford) [examined].

Cataulacus brookei Syntype workers, female, male, BORNEO: Sarawak (Haviland) (MHN, Geneva) [examined].

Additional References

 * Debout, G., A. Dalecky, et al. (2002). "Isolation and characterization of polymorphic microsatellites in the tropical plant-ant Cataulacus mckeyi (Formicidae: Myrmicinae)." Mol. Ecol. Notes 2: 459-461.