Rotastruma recava

Rotastruma recava
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Crematogastrini
Genus:	Rotastruma
Species:	R. recava
Binomial name
Rotastruma recava Bolton, 1991 Specimen labels

Bolton noted that nests contained more than one dealate queen. Specimens have been collected in rainforest from dead twigs.

Identification

This species is easily distinguished from Rotastruma epispina and Rotastruma stenoceps by the concave occipital margin, convex lateral margin of head and sides of head not having hairs in the worker caste (Hosoishi et al., 2021).

Keys including this Species

• Key to Rotastruma species

Distribution

Distribution based on Regional Taxon Lists

Indo-Australian Region: Borneo (type locality), Indonesia, Malaysia, Singapore.

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.

Castes

Worker

Images from AntWeb

Worker. Specimen code casent0010808. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by UCDC, Davis, CA, USA.

Worker. Specimen code casent0102499. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by MHNG, Geneva, Switzerland.

Queen

Images from AntWeb

Queen (alate/dealate). Specimen code casent0010926. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by UCDC, Davis, CA, USA.

Queen (alate/dealate). Specimen code casent0010927. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by UCDC, Davis, CA, USA.

Male

Images from AntWeb

Male (alate). Specimen code casent0010928. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by UCDC, Davis, CA, USA.

Nomenclature

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

• recava. Rotastruma recava Bolton, 1991: 9, figs. 12, 14 (w.q.) BORNEO (East Malaysia: Sarawak), SINGAPORE.
  • Type-material: holotype worker, 20 paratype workers, 4 paratype queens.
  • Type-locality: holotype Malaysia: Sarawak, 4th Division, G. Mulu N.P., 22.v.1978, mixed dipterocarp forest, on tree (N.M. Collins); paratypes: 18 workers, 2 queens Singapore: Bukit Timah Forest, 15.iii.1973 (D.H. Murphy), 2 workers, 2 queens Singapore: Bukit Timah, 100 m., 8.iv.1989, no. 10254, ex dead twig, vine, rainforest (P.S. Ward).
  • Type-depositories: BMNH (holotype); BMNH, MCZC, MHNG (paratypes).
  • Status as species: Bolton, 1995b: 382; Pfeiffer, et al. 2011: 51.
  • Distribution: Malaysia (Sarawak), Singapore.

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

Description

Worker

Holotype. TL 3.6, HL 0.80, HW 0.69, CI 86, SL 0.56, SI 81, PW 0.48, AL 0.94. Maximum diameter of eye 0.24 (0.35 x HW). Mandibles finely longitudinally striolate. Central strip of dorsum of head with a number of longitudinal costulae which may run the length of the head or may be broken or interrupted. Occipital margin distinctly concave in full-face view, the sides of the head in front of the large eyes convex. Median portion of clypeus with 3 longitudinal carinae. Dorsal alitrunk with predominantly longitudinal sharp rugulae; cross-meshes present, especially on pronotum. Sides of alitrunk marginate, margination sharpest on mesonotum and propodeum. Propodeal spines long, depressed and down-curved along their length. Sides of alitrunk with weak longitudinal rugulae. Petiole and postpetiole rugulose to reticulate-rugulose dorsally. First gastral tergite unsculptured except for sparse short basi gastral costulae and feeble superficial reticular patterning. Standing hairs present on all dorsal surfaces, short fine and acutely pointed. Colour yellow, the first gastral tergite with a broad brown band.

Paratype. TL 3.6-4.0, HL 0.80-0.84, HW 0.66-0.70, CI83-86, SL 0.56-0.60, SI 81-86, PW 0.48-0.52, AL 0.94-1.02. Maximum diameter of eye 0.24-0.26 (0.35-0.37 x HW) (10 measured). As holotype.

Queen

Paratype. TL 3.9-4.0, HL 0.80-0.81, HW 0.69-0.70, CI 85-86, SL 0.54-0.56, Sl 78-81, PW 0.56-0.58, AL 1.08-1.12. Maximum diameter of eye 0.26-0.28 (0.37-0.40 x HW) (4 measured). The females are small, only the same size as the workers or slightly larger. Alate when virgin and with a complete complement of flight sclerites.

Type Material

Holotype worker, East Malaysia: Sarawak, 4th Division G. Mulu NP, 22.v.1978, mixed dipterocarp forest, on tree (N. M. Collins) (The Natural History Museum).

Paratypes, 18 workers and 2 females, Singapore: Bukit Timah Forest, 15.iii.1973 (D. H. Murphy); 2 workers and 2 females, Bukit Timah, 100 m, 8.iv.1989, no. 10254, ex dead twig, vine, rainforest (P. S. Ward) (BMNH; Museum of Comparative Zoology; Musee d'Histoire Naturelle Genève).

Based on Hosoishi et al. (2021): Holotype and one paratype worker images examined.

• Holotype: Malaysia • worker; Sarawak, 4th Division G. Mulu NP; 22 May 1978; N. M. Collins leg.; type image CASENT0901995 of AntWeb (http://www.antweb.org/); BMNH.
• Paratype: SINGAPORE • one worker; Bukit Timah Forest; 15 Mar 1973; D. H. Murphy leg.; type image CASENT0178523 of AntWeb (http://www.antweb.org/); MCZC.

References

• Bolton, B. 1991. New myrmicine genera from the Oriental Region (Hymenoptera: Formicidae). Syst. Entomol. 16: 1-13. (page 9, figs. 12, 14 worker, queen described)
• Hosoishi, S., Yamane, S., Sokh, H. 2021. A third species of the rare ant genus Rotastruma (Hymenoptera, Formicidae) from Cambodia, with illustrated generic diagnoses and key to species. Deutsche Entomologische Zeitschrift 68, 225–233 (doi:10.3897/dez.68.63478).
• Wang, W.Y., Soh, E.J.Y., Yong, G.W.J., Wong, M.K.L., Benoit Guénard, Economo, E.P., Yamane, S. 2022. Remarkable diversity in a little red dot: a comprehensive checklist of known ant species in Singapore (Hymenoptera: Formicidae) with notes on ecology and taxonomy. Asian Myrmecology 15: e015006 (doi:10.20362/am.015006).

References based on Global Ant Biodiversity Informatics

• Bolton B. 1991. New myrmicine genera from the Oriental Region (Hymenoptera: Formicidae). Systematic Entomology 16:1-13.
• Pfeiffer M.; Mezger, D.; Hosoishi, S.; Bakhtiar, E. Y.; Kohout, R. J. 2011. The Formicidae of Borneo (Insecta: Hymenoptera): a preliminary species list. Asian Myrmecology 4:9-58
• Zryanin V. A. 2011. An eco-faunistic review of ants (Hymenoptera: Formicidae). In: Structure and functions of soil communities of a monsoon tropical forest (Cat Tien National Park, southern Vietnam) / A.V. Tiunov (Editor). – M.: KMK Scientific Press. 2011. 277 р.101-124.