Recurvidris recurvispinosa

Recurvidris recurvispinosa is the most widely distributed member of the genus. In Thailand it occurs in areas north of the Isthmus of Kra and in various types of forest such as dry evergreen forest, mixed deciduous forest and dry dipterocarp forest (Jaitrong and Wiwatwitaya 2015), while in Japan this rarely encountered species nests in soil or under stones in forests or forest margins(Japanese Ant Image Database). In India, Harshana & Dey (2021) collected this species from leaf litter and on the forest floor near a tree base. They found the collembolan Sminthurides parvulus (Krausbauer, 1898) within the mandibles of one specimen, suggesting that these ants feed on small arthropods in leaf litter and soil.

Identification
Jaitrong and Wiwatwitaya (2015) - Recurvidris recurvispinosa is closely related to Recurvidris hebe (Sulawesi) in having 4-dentate mandibles, and the basal mandibular tooth being enlarged and bidenticulate apically. R. recurvispinosa differs from R. hebe in the following points: in profile propodeal spine and petiolar peduncle relatively short and stout (relatively long and narrow in R. hebe); with head in full-face view, occipital corners round (more broadly round in R. hebe); mesosoma finely reticulate-punctate to reticulate-granular (superficially sculptured in R. hebe).

Distribution
Recurvidris recurvispinosa is distributed from India, through China, to Taiwan and Japan. In Japan it has been recorded only from Ishigaki and Iriomote Islands in the Yaeyama Island Group (Japanese Ant Image Database).

Distribution based on Regional Taxon Lists
Oriental Region: India, Laos, Myanmar, Nepal, Sri Lanka, Taiwan, Thailand. Palaearctic Region: China, Japan.

Nomenclature

 * . Trigonogaster recurvispinosus Forel, 1890b: cix, fig. (w.) INDIA (Maharashtra).
 * Type-material: syntype workers (number not stated).
 * Type-locality: India: Poona (= Pune) (R.C. Wroughton).
 * Type-depository: MHNG.
 * Wheeler, W.M. 1927d: 5 (m.).
 * Combination in Recurvidris: Bolton, 1992: 46.
 * Status as species: Dalla Torre, 1893: 72; Forel, 1903a: 699; Bingham, 1903: 285; Emery, 1924d: 210; Wheeler, W.M. 1927d: 5; Wheeler, W.M. 1930h: 64; Chapman & Capco, 1951: 161; Ettershank, 1966: 160 (redescription); Wu, J. & Wang, 1992: 1308; Bolton, 1992: 46 (redescription); Bolton, 1995b: 377; Wu, J. & Wang, 1995: 86; Mathew & Tiwari, 2000: 320; Sheela, et al. 2000: 95; Zhou, 2000: 301 (in key); Zhou, 2001b: 110; Imai, et al. 2003: 112; Lin & Wu, 2003: 66; Ghosh, et al. 2005: 32; Jaitrong & Nabhitabhata, 2005: 41; Terayama, 2009: 178; Guénard & Dunn, 2012: 52; Jaitrong & Wiwatwitaya, 2015: 110 (redescription); Bharti, Guénard, et al. 2016: 44; Jaitrong, Guénard, et al. 2016: 38; Jaitrong, Tokeeree, et al. 2019: 59 (in key); Dias, R.K.S. et al. 2020: 89.
 * Distribution: China, India, Japan, Laos, Myanmar, Nepal, Sri Lanka, Taiwan, Thailand.

Worker
Jaitrong and Wiwatwitaya (2015) - (n = 15). TL 1.70-1.85 mm, HW 0.36-0.41 mm, HL 0.41-0.43 mm, SL 0.33-0.35 mm, PW 0.21-0.25 mm, ML 0.53-0.54 mm, CI 85-96, SI 87-95.

Head in full-face view narrow, subreticular and slightly longer than broad, with posterior margin almost straight or feebly concave. Eye 0.10 mm in maximum diameter, with 6-7 ommatidia along longest axis. Antennal scape extending posteriorly slightly beyond posterolateral corner of head. Masticatory margin of mandible with four sharp teeth, fourth (basal) tooth enlarged and bidenticulate; basal margin of mandible unarmed. Propodeal spine stout, upcurved. Clypeus with distinct paired carinae, its anterior margin weakly convex. Mesosoma relatively slender; promesonotum in profile weakly convex dorsally and sloping gradually to metanotal groove. Propodeum in profile with feebly convex dorsal outline; recurved propodeal spine long and narrow. Propodeal declivity with infradental lamella or ridge linking propodeal spine to metapleural lobe. Peduncle of petiole relatively short, with its dorsal outline distinctly concave and ending posteriorly in blunt angle, its ventral outline convex. Subpetiolar process varying from a tooth to short spine.

Dorsa of head and mesosoma usually finely reticulate-punctate to reticulate-granular; on head the sculpture usually weaker on dorsum behind frontal lobes, and stronger posteriorly and laterally. Sculpture on pronotum much weaker than that on head. Petiole finely reticulate. Postpetiole superficially reticulate. Gaster smooth and shiny.

Head with relatively sparse short hairs; promesonotum with sparse short hairs (less than ten hairs); longest pronotal hairs 0.07 mm long. Hairs absent from propodeal dorsum. Petiole with two dorsal pairs of short hairs. Postpetiole with two dorsal pairs and one ventrolateral pair of short hairs. Body colour yellow to yellowish brown.

Type Material
Jaitrong and Wiwatwitaya (2015) - Syntype workers from India, Poona (R.C. Wroughton).

References based on Global Ant Biodiversity Informatics

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