Polyrhachis arachne

Polyrhachis arachne was found nesting in the internodes of bamboo, with each of these containing 687 workers (median) (n = 10, range: 125-1088 workers). This ant is also known to tend mealybugs Kermicus wroughtoni outside their nests (in leaf pavilions). Another study found P. arachne within a few nest internodes (2-4, n = 10) that contained 33-340 workers and also in a larger number of leaf pavilions (13 - 23, n = 3) that contained 3-174 workers per pavilion (n = 22). (Dorow and Maschwitz 1990, Schellerich-Kaaden et al. 1997)

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia. Oriental Region: Thailand.

Biology
Often found nesting in dead culm internodes, i.e. where scale insects cannot live, while cultivating its trophobionts in silk pavilions under bamboo leaves (Dorow and Maschwitz 1990). P. arachne is known to narrow larger nest entrances with silk and detritus, unlike Polyrhachis schellerichae.

Nomenclature

 *  arachne. Polyrhachis arachne Emery, 1896f: 249 (w.q.) INDONESIA (Java). Wheeler, G.C. & Wheeler, J. 1990b: 758 (l.). Combination in P. (Myrmhopla): Emery, 1925b: 192. Senior synonym of uncinata: Emery, 1898a: 230. See also: Bingham, 1903: 390; Dorow & Maschwitz, 1990: 73.
 * uncinata. Polyrhachis uncinata André, 1896b: 252 (w.) THAILAND. Junior synonym of arachne: Emery, 1898a: 230.