Eurhopalothrix chapmani

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Eurhopalothrix chapmani
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Eurhopalothrix
Species: E. chapmani
Binomial name
Eurhopalothrix chapmani
Taylor, 1990

Eurhopalothrix chapmani casent0280775 p 1 high.jpg

Eurhopalothrix chapmani casent0280775 d 1 high.jpg

Specimen Labels

The single type, a worker, was collected from the base of a rotten pole in a bamboo thicket.

Identification

E. chapmani seems to be close to Eurhopalothrix heliscata and both species are probably related to Eurhopalothrix procera. (Taylor 1990)

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Indo-Australian Region: Philippines (type locality).

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Little is known about the biology of most species in this genus. Nests are rarely found, and queens and males have not been collected for many species. Longino (2013) summarized their biology "Eurhopalothrix specimens are encountered almost exclusively in samples from mass extraction techniques that recover small arthropods in sifted litter, rotten wood, and soil. Densities, at least in the northern Neotropics, are usually low, with workers occurring in < 10% of quantitative samples of 1 m2 litter plots, but occasionally may reach densities as high as 40% of samples. Live colonies of Old World Eurhopalothrix were observed by Wilson (1956) and Wilson and Brown (1984), and a Costa Rican colony of Basiceros manni was observed by Wilson and Hölldobler (1986). All basicerotines, including Eurhopalothrix, are thought to be predators in tropical leaf litter, relying on stealth or sit-and-wait techniques. Sampled specimens are often coated with a thin layer of clay, especially on the face, which is thought to function as camouflage, enhancing crypsis (Hölldobler & Wilson, 1986). Highly specialized spatulate setae may be instrumental in acquisition and adherence of the clay layer (Hölldobler & Wilson, 1986)."

Castes

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • chapmani. Eurhopalothrix chapmani Taylor, 1990b: 406, figs. 5-7, 23, 45 (w.) PHILIPPINES.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

Worker

General features as illustrated. All Class A attributes present, with those of Class B, unless otherwise indicated. Dimensions (mm): HL 1.01; HW 1.05; CI 104; ML 0.29; MI 29; SL 0.64; SI 62; PW 0.61; WL 1.21. Outer mandibular borders in frontal view broadly and more-or-less evenly convex. Eyes rather small, with 6-8 facets. Posterior occipital angles approximately 90°. Promesonotal profile almost straight, very shallowly and broadly depressed about the mesonotal/propodeal junction. Propodeal dorsum only slightly depressed posteriorly between the bases of the teeth.

A single pair of specialised erect hairs (one of which has been lost by the holotype) bilaterally near the midline on posterior part of frons, the hairs small and only slightly clubbed. Similar hairs on last 3 exposed gastral sternites, and posteromedially on first tergite; otherwise lacking. Pubescence reduced, its hairs small and scattered, except on posterior part of frons, occipital lobes, and dorsa of pronotum, petiole and postpetiole. Resembling Eurhopalothrix heliscata with the following salient differences:

(1) Sculpturation finer and less strongly delimited, as follows:

Mandibles coarsely punctate with shining interspaces, somewhat rugose at their bases. Head, mesosoma and nodes moderately finely punctate-shagreened (unlike other species described here), sculpturing less sharply defined elsewhere on mesosomal dorsum, and especially on waist nodes; frons and pronotal dorsum tending to be more rugulose, though very finely so; gastral dorsum slightly more finely sculptured than elsewhere.

(2) Generally less 'craggy' in appearance. Surfaces of frons and occipital lobes smoothly rounded, where in E. heliscata the frons has a transverse anterior tumosity behind the broadly depressed fronto-clypeal suture, relatively strong swellings under each of the two enlarged cephalic hairs, and the apices of the frontal lobes are somewhat more abruptly swollen anteriorly. Postpetiolar dorsum almost entirely convexly curved, with a relatively featureless surface, where in E. heliscata its disc is more-or-less flattened anteromedially, and somewhat depressed behind the slightly raised rim-like anterior edge; the posterior portion of the dorsum is bitumose when viewed obliquely along the long-axis of the body, with a shallowly depressed median channel running back from the anteromedian section.

(3) Pronotal dorsum a transversely even arch, where in E. heliscata it is distinctly bitumose in transverse profile.

(4) Petiolar node in dorsal view about as long as wide, v. distinctly longer than wide in E. heliscata.

Type Material

Philippines: Luzon: Ateneo De Manila, Quezon City (l4°38'N.,121°02'E.). Known only from the unique worker holotype, collected from the base of a rotten pole in a bamboo thicket (B. B. Lowery, 8.vii.I978). In Australian National Insect Collection (type No. 7776); the specimen gold-palladium coated for SEM study.

Etymology

Named for the late American Philippines teacher and myrmecologist James W. Chapman.

References

  • Taylor, R. W. 1990c. New Asian ants of the tribe Basicerotini, with an on-line computer interactive key to the twenty-six known Indo-Australian species (Hymenoptera: Formicidae: Myrmicinae). Invertebr. Taxon. 4: 397-425 (page 406, figs. 5-7, 23, 45 worker described)