Rhytidoponera arborea

This rainforest species is probably arboreal and forages on low vegetation and on the ground.

Rhytidoponera arborea
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Ectatomminae
Tribe:	Ectatommini
Genus:	Rhytidoponera
Species:	R. arborea
Binomial name
Rhytidoponera arborea Ward, 1984 Paratype Specimen Label

Identification

In comparison with other pulchella-group species having a dense mat of appressed pubescence on the gastric tergies, arborea is either larger (HW >1.10 in arborea, HW < 1.0 in pulchella and insularis) or differs in pilosity (depilis has little erect pilosity; terrestris is a little more setose than arborea). Rhytidoponera arborea and Rhytidoponera terrestris are rather similar, but the differences between them appear to be consistent. The occipital lobes are a little better developed in arborea (OLI 0.43-0.46 in arborea, 0.40-0.44 in terrestris) and not as far apart (OLD 0.62-0.66 in arborea, 0.66-0.71 in terrestris) (samples of 10 and 13 workers for arborea and terrestris, respectively). The scapes and femora of arborea have fewer standing hairs, as shown by the following ranges of setal counts (data on pulchella are included for comparison):

Finally, arborea and terrestris occur sympatrically (Col d' Amieu; vicinity of Col de Ho), and they are substituted for alternate alleles at three allozyme loci (amylase, esterase, and gluatamate oxaloacetate transaminase).

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -21.6° to -21.60000038°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Australasian Region: New Caledonia (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Rhytidoponera arborea has been collected in rainforest, from 40 to 450 m elevation, where workers were observed foraging on low foliage and on the ground. The present records suggest that this species may favor arboreal nesting sites; one colony was located in a cavity of a living rainforest tree, 10 m above the ground; another was nesting in an epiphytic fern (Asplenium) growing on a large boulder.

Castes

Worker

.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• arborea. Rhytidoponera arborea Ward, 1984: 153, figs. 41, 42, 47, 48 (w.) NEW CALEDONIA.
  • Type-material: holotype worker, paratype workers (number not stated, “a series”).
  • Type-locality: holotype New Caledonia: Col d’Amieu, 360 m., 21°36’S, 165°48’E, 20.ii.1977, acc. no. 2268, nest in cleft of rainforest tree (P.S. Ward); paratypes with same data.
  • Type-depositories: ANIC (holotype); ANIC, BMNH, BPBM, MCZC, MNHN, PSWC (paratypes).
  • Status as species: Taylor, 1987a: 71; Bolton, 1995b: 378.
  • Distribution: New Caledonia.

Type Material

• Holotype, worker, Col D'Amieu Stn, New Caledonia, Ward,P.S., ANIC32-011963, Australian National Insect Collection.
• Paratype, 1 worker, Col D'Amieu Stn, New Caledonia, Ward,P.S., ANIC32-011964, Australian National Insect Collection.
• Paratype, 1 worker, Col D'Amieu Stn, New Caledonia, The Natural History Museum.

Description

Type Material

Holotype worker. New Caledonia: Col d'Amieu Stn, 360 m, 21°36′0″S 165°48′0″E 20. ii. 1977, nest in cleft of rainforest tree, 10 m above ground (P.S. Ward acc. No. 2268) (ANIC Type No. 7580).

Paratype workers. A series of nidoparatype workers, same locality, date, and accession number (ANIC, BPBM, MBNH, MCZ, PSW).

Non-paratypic material. Additional material from 6 other localities which is considered to be conspecific is listed below (under Material Examined).

Measurements

Holotype worker. HW 1.31, WL 1.96, CI 0.93, MI 0.34, SI 0.97, SL12 0.20, SSC 9, FSC 0.

Paratype workes and other material. HW 1.14-1.32, WL 1.78-2.00, CI 0.86-).92, MI 0.30-0.40, SI 0.98-1.12, (n=20); SL12 0.18-0.21, SSC 7-10, FSC 0-2 (n = 9).

Diagnosis of Worker

Anterior clypeal margin obtusely angulate Frontal lobes expanded laterally and covering most of the antennal insertions; frontal carinae subparallel, converging to 85-90% of their maximum distance, the later (FCD) <1/2 the head width (FCI 0.41-0.46). Head quadrate, longer than wide, the sides weakly convex; occipital margin flat or very slightly concave, in full-face view. Eyes protruding slightly in dorsal view, OI 0.22-0.27. In lateral view, the frons rounds evenly into the vertex, the occipital lobes protruding slightly (OLI 0.43-0.46, OLD 0.62-0.66). Pronotum relatively slender, PI 0.76-0.82. Promesonotal suture distinct, obtusely V-shaped in dorsal view. Mesopropodeal impression indistinct; basal face of propodeum weakly differentiated from the declivitous face, the latter a little longer than the former, in lateral view. Inferior pronotal tooth well developed. Petiole as illustrated: node robust, somewhat rounded, with a short anterior peduncle (LPI 053-0.58; DNI 0.90-1.01; PN12 0.44-0.50); subpetiolar process consisting of a long, spiniform tooth (SL12 0.18-0.21; SPI 0.13-0.23).

Mandibles striate. Head predominantly rugose, the inter-rugal punctures smooth and shining.. Mesosoma and petiolar node rugose with interspaces shining, and with some rugulose sculpture on the sides; rugae tending to show a transverse orinetation on the propodeum. Abdominal tergite III with irregular, transverse striae, becoming rugostriate to rugulose anterolaterally. Abdominal tergite IV with weak, transverse, striolate-imbricate parts of the body. Standing hairs sparse on the upper surface of the femora (FSC 0-2; HSC 0-6, nearly always on the apical half). Abdominal tergites III and IV with a distinct mat of appressed pubescence. Black, with dark brown mandibles, antennae, and legs; the apical funicular and tarsal segments a lighter, ferrugineous brown.

References

Ward, P. S. 1984. A revision of the ant genus Rhytidoponera (Hymenoptera: Formicidae) in New Caledonia. Aust. J. Zool. 32: 131-175 (page 153, figs. 41, 42, 47, 48 worker described)

References based on Global Ant Biodiversity Informatics

• CSIRO Collection
• Jennings J. T., L. Krogmann, and C. Burwell. 2013. Review of the hymenopteran fauna of New Caledonia with a checklist of species. Zootaxa 3736(1): 1-53.
• Taylor R. W. 1987. A checklist of the ants of Australia, New Caledonia and New Zealand (Hymenoptera: Formicidae). CSIRO (Commonwealth Scientific and Industrial Research Organization) Division of Entomology Report 41: 1-92.
• Ward P. S. 1984. A revision of the ant genus Rhytidoponera (Hymenoptera: Formicidae) in New Caledonia. Aust. J. Zool. 32: 131-175.
• Ward P. S. 1985. Taxonomic congruence and disparity in an insular ant fauna: Rhytidoponera in New Caledonia. Systematic Zoology 34: 140-151.