Nylanderia bourbonica

This is a tramp species commonly encountered in the tropics and subtropics and has spread across large areas by human commerce, and is associated with human disturbance (Klotz et al 1995; Wilson and Taylor 1967; Wetterer 1998). It is commonly found in most parts of India, however, it was not found in Northwest Himalaya. The workers were collected in leaf litter, rotting wood, underneath stones, on walls of buildings and other establishments.

Identification
Wachkoo and Bharti (2015) - India - Propodeum is on the same plane to remainder of dorsum and unicolorous dark body resembles those of Nylanderia birmana, but N. bourbonica can be easily distinguished by smooth or fine punctulae on head and mesosomal dorsum whilst in N. birmana head and mesosomal dorsum are covered with a dense network of microreticulate sculpture.

Distribution based on Regional Taxon Lists
Afrotropical Region: Kenya, Saint Helena, United Republic of Tanzania. Australasian Region: Australia, New Caledonia. Indo-Australian Region: Fiji, Guam, Hawaii, Krakatau Islands, Marshall Islands, Micronesia (Federated States of), New Guinea, Niue, Northern Mariana Islands, Palau, Pitcairn, Samoa, Solomon Islands, Tokelau, Tonga, Vanuatu, Wallis and Futuna Islands. Malagasy Region: Mauritius, Réunion, Seychelles. Nearctic Region: United States. Neotropical Region: Cuba, Mexico. Oriental Region: Bangladesh, India, Nicobar Island. Palaearctic Region: China.



Worker
Additional worker images can be found here

Queen
Additional queen images can be found here

Male
Additional images can be found here

Nomenclature

 *  bourbonica. Prenolepis nodifera r. bourbonica Forel, 1886f: 210 (w.q.m.) REUNION I. Combination in Pr. (Nylanderia): Forel, 1912a: 73; in Paratrechina (Nylanderia): Emery, 1925b: 219; in Nylanderia: Wheeler, W.M. 1936f: 16; in Paratrechina: Trager, 1984b: 147; in Nylanderia: LaPolla, Brady & Shattuck, 2010a: 127. Raised to species: Forel, 1891b: 82. Senior synonym of bengalensis, hawaiensis, skottsbergi: Wilson & Taylor, 1967: 88. Current subspecies: nominal plus farquharensis, ngasiyana.
 * bengalensis. Prenolepis bourbonica r. bengalensis Forel, 1894c: 408, fig. 3 (w.q.m.) INDIA. Combination in Pr. (Nylanderia): Forel, 1912a: 73; in Paratrechina (Nylanderia): Emery, 1925b: 219; in Nylanderia: Wheeler, W.M. 1936f: 16. Raised to species: Bingham, 1903: 329. Subspecies of bourbonica: Mann, 1921: 476. Junior synonym of bourbonica: Wilson & Taylor, 1967: 88.
 * hawaiensis. Prenolepis bourbonica r. hawaiensis Forel, 1899a: 120 (w.q.m.) HAWAII. Combination in Paratrechina (Nylanderia): Emery, 1925b: 219. Junior synonym of bourbonica: Wilson & Taylor, 1967: 88.
 * skottsbergi. Prenolepis (Nylanderia) bourbonica subsp. skottsbergi Wheeler, W.M. 1922f: 318 (w.) EASTER I. Combination in Paratrechina (Nylanderia): Emery, 1925b: 219. Junior synonym of bourbonica: Wilson & Taylor, 1967: 88.

Worker
Wachkoo and Bharti (2015) - TL 2.11-3.04 mm; HL 0.58-0.83 mm; HW 0.50-0.74 mm; EL 0.15-0.23 mm; SL 0.62-0.97 mm; PW 0.35-0.53 mm; PrFL 0.51-0.79 mm; PrFW 0.16-0.20 mm; WL 0.69-1.08 mm; GL 0.83-1.14 mm. Indices: CI 87.03-89.84; SI 123.11-135.38; REL 26.42-28.00 (n = 20).

Head is subquadrate; slightly longer than wide, distinctly wider posteriorly than in front, lateral margins convex, posterior margin shallowly concave to convex with rounded posterolateral corners. Clypeus carinate in the middle; anterior clypeal margin, medially nearly straight to strongly concave. Eyes large, broadly rounded and weakly convex; covering approximately one-third of lateral cephalic margin; three ocelli present. Antennae long, scape surpasses posterior margin by about two-fifths their length.

Metanotal groove strongly developed, in lateral view interrupts the regular promesonotal convexity from propodeum; metanotal area distinct. Dorsal face of propodeum rounded, about the same length as declivitous face; in lateral view, its highest part on the same plane to remainder of dorsum, dorsally dome-like. Petiole low and transverse, subtriangular in lateral view, inclined forward, with posterior face longer than anterior face.

Cuticle smooth and shining covered with fine punctulae. Body covered with fine pubescence, which is lacking on propodeal declivity and petiole. Scape with scattered erect macrosetae and a dense layer of pubescence (SMC = 45e60). Mesosoma with erect macrosetae of varying lengths concentrated on posterior pronotum and mesonotum (PMC = 8e12; MMC = 3e6).

Body is brown to black.

Queen
Wachkoo and Bharti (2015) - HL 0.69-0.71 mm; HW 0.68-0.72 mm; EL 0.21-0.22 mm; SL 0.67-0.68 mm; PrFL 0.61-0.63 mm; PrFW 0.18-0.20 mm; WL 1.42-1.47 mm. Indices: CI 98.55-101.41; SI 94.44-98.53; REL 30.43-30.99 (n = 2).

Generally, matches worker description, with modifications expected for caste and the following differences: head subtriangular with feebly concave posterior margin; anterior clypeal margin strongly concave; petiole concave above; coloration pattern similar to adult workers; body covered with much dense pubescence than in workers (SMC 50 = 65; PMC = 4-6; MMC = 45-54.

Male
Wachkoo and Bharti (2015) - HL 0.59-0.62 mm; HW 0.48-0.51 mm; EL 0.23-0.25 mm; SL 0.75-0.78 mm; PrFL 0.65-0.69 mm; PrFW 0.14- 0.16 mm; WL 0.86-0.91 mm. Indices: CI 81.36-82.26; SI 152.94- 156.25; REL 38.98-40.32 (n = 3).

Head is oval; longer than wide; eyes large, subglobulose, projecting beyond head outline in full-face view; three prominent ocelli present. Antennae filiform, scapes long, surpass posterior margin by about half their length. Mandibles slender with prominent, pointed apical and small preapical tooth, remainder of masticatory margin smooth, with indistinct, rounded basal angle that seamlessly blends into inner mandibular margin.

Mesosoma modified for the presence of wing; propodeum indistinct, lower than remainder of notum with very short dorsal face and long declivitous face; petiole as in worker.

Genitalia: Parameres strongly emarginate with apical and ventral margins produced as finger like projections; long setae extending off of parameres. Cuspi rounded distally with many short peg-like teeth; digiti weakly paddle-shaped, about double the length of the digiti; penis valves projecting past parameres with apices of each penisvalva directed posterolaterally.

Sculpture very much reduced than in worker caste; body mostly smooth and shiny at most with fine punctations. Vestiture and color as in worker caste (SMC 22 = 28; PMC = 0; MMC = 27-32).