Pheidole vigilans (F. Smith)

Sarnat, Eli M., Fischer, Georg, Guenard, Benoit & Economo, Evan P., 2015, Introduced Pheidole of the world: taxonomy, biology and distribution, ZooKeys 543, pp. 1-109 : 49-51

Taxon classification Animalia Hymenoptera Formicidae

Pheidole vigilans (F. Smith) Figs 87, 88O

Pheidole vigilans . Atta vigilans Smith, F. 1858: 166 (w.) AUSTRALIA, Melbourne [BMNH, MCZC]. Combination in Aphaenogaster : Dalla Torre 1893:108; in Pheidole : Emery 1915a: 69.

Pheidole dolichocephala . Pheidole dolichocephala André 1896: 262 (s.) AUSTRALIA, Western Australia [MNHN]. Junior synonym of vigilans : Brown 1971: 13.

Pheidole parallela . Pheidole ampla var. parallela Forel 1902a: 435 (s.w.m.) AUSTRALIA, N.S.W. (Froggatt) [ANIC]. Junior synonym of vigilans : Brown 1971: 13.

Pheidole yarrensis . Pheidole ampla var. yarrensis Forel 1902a: 434 (s.w.q.) AUSTRALIA, Yarra districts, Victoria (Froggatt) [MHNG]. Junior synonym of vigilans : Brown 1971: 13.

Pheidole norfolkensis . Pheidole ampla subsp. norfolkensis Wheeler, W.M. 1927: 134, fig. 3 (s.w.) AUSTRALIA, Norfolk Island (A.M. Lea) [MCZC]. Donisthorpe 1941: 91 (q.m.). Junior synonym of vigilans : Brown 1971: 13.

Diagnosis among introduced Pheidole .

Smooth yellowish to reddish brown. MajorHW 1.30, HL 1.43, SL 0.68, CI 91, SI 52. Head subquadrate (Fig. 7); glossy, lacking foveolate ground sculpture. Posterolateral lobes lacking sculpture (including foveolate ground sculpture, carinae and rugae) posterior to maximum extent of antennal scapes in repose (Fig. 9). Hypostomal bridge with two well-developed inner teeth but lacking a median tooth (Fig. 19). Promesonotal dorsum glossy, lacking foveolate ground sculpture or striae. Promesonotum in profile forming a single dome (Fig. 4), lacking a distinct mound or prominence on the posterior slope. Metapleuron almost completely glossy with strongly reduced carinulae and lacking punctation (Fig. 17). Petiolar node mostly glossy (Fig. 17), not covered by punctate sculpture. Postpetiole not swollen relative to petiole (Fig. 3). MinorHW 0.55, HL 0.58, SI 0.55, CI 95, SI 101. Head predominantly glossy (Fig. 36), lacking punctation and or rugae above eye level. Antennal scapes surpass posterior head margin by approximate distance of eye length (Fig. 40). Mesopleuron entirely glossy (Fig. 51a). Promesonotum in profile forming a single dome (Fig. 42), lacking a distinct mound or prominence on the posterior slope. Propodeal spines weakly produced and dentiform (Fig. 51b). Petiole almost entirely glossy. Postpetiole not swollen relative to petiole (Fig. 3).

Identification, taxonomy and systematics.

Pheidole vigilans is a large, light colored, glossy species native to Australia and introduced in New Zealand. The species belongs to an Old World clade centered in Australia. The glossy head of the majors and minors give it a superficial appearance to Pheidole megacephala , but it is substantially larger than that species. Additionally, the postpetiole of Pheidole proxima is not swollen relative to the petiole (Fig. 3) as in Pheidole megacephala (Fig. 1), and the head of the major is subquadrate (Fig. 7), while that of Pheidole megacephala is more heart-shaped (Fig. 6). Readers are referred to the section under Pheidole proxima and Pheidole rugosula for a discussion of how to differentiate it from the other Pheidole species established in New Zealand. Additional taxonomy of these species is discussed in ( Berry et al. 1997). Within Australia, there are many taxa similar to Pheidole vigilans and its close relative Pheidole ampla Forel. However, a revision of that fauna is required before it can be reliably diagnosed there.

Biology.

Records show it has established in urban areas and been found with fruit, in gardens, indoors and nesting in failing pasture ( Berry et al. 1997).

Distribution.

Pheidole vigilans is considered endemic to the south eastern corner of Australia ( Brown 1971). Heterick et al. (2013) reported Pheidole vigilans as introduced to Perth in Western Australia. The species was first collected outside of Australia in Kerikeri, New Zealand in 1956, and remains the least frequently collected Pheidole species in New Zealand ( Berry et al. 1997; Cumber 1959). Although Pheidole ampla subsp. norfolkensis Wheeler was originally described as endemic to the Norfolk Islands, Brown (1971) later proposed that the species was introduced to those islands.

Risk statement.

Pheidole vigilans is not considered a pest in New Zealand, but it has been collected from urban areas and may be a minor garden nuisance ( Harris et al. 2005c).