Pheidole fervens

Fischer & Fisher (2013): Pheidole fervens, described from Singapore, is a widespread invasive species and could be native to the Oriental or the Oceanic region (Eguchi 2004, Wilson & Taylor 1967). It usually nests in soil or under stones and usually prefers disturbed habitats (Eguchi 2004). On Fiji it was collected in elevations between 1–800 m and tended to inhabit several different habitats from forest edge and mangrove forest to disturbed and undisturbed rainforest. On Mauritius, which seems to be its western distribution limit, this ant was found in the leaf litter of lowland rainforest (200 m elevation). As with most other introduced ants, such as Pheidole teneriffana, it is unclear what effect, if any, P. fervens might have on the rest of the local ant fauna. Considering that the ecosystems of the Mauritius islands have been severely altered and disturbed since the arrival of human settlers several hundred years ago, and native species must also contend with the invasions of introduced organisms (Fisher 2005, Ward 1990), parts of the original ant fauna might have been marginalized or driven to extinction long ago. We speculate that the scarcity of P. fervens specimens in Mauritius ant collections and its presence in the rainforest means that this ant has not yet become an invasive and dominant aggressor toward other ant species. Nevertheless, efforts to further investigate the presence and activity of introduced Pheidole species are worthwhile, especially in the few remaining undisturbed habitats.

Identification
Eguchi (2008) - This medium-sized species with general habitus is similar to Pheidole binghamii, Pheidole elongicephala, Pheidole indica, Pheidole ochracea and Pheidole plagiaria among Indo-Chinese species. P. fervens is well separated from P. indica which has the following characteristics: eye relatively large (maximal diameter of eye much longer than antennal segment X in the major, and as long as or a little longer than X in the minor); in the major propodeal spine is relatively broadly based (see Eguchi 2004).

Posterior margin of head in full-face view is more deeply and narrowly concave in the major of P. binghamii, P. elongicephala and P. ochracea than in that of P. fervens, and sculpture on dorsum of vertexal lobe is usually stronger in the major of the former three.

The major of P. fervens is separated from that of P. plagiaria which has the following characteristics: posterior margin of head in full-face view deeply concave; the rugulae running almost transversely along posterior margin of vertexal lobe.

Key to Pheidole of North Vietnam

Distribution
Known from N. Vietnam, Manchurian subregion (southern part only), Oriental region, Austro-Malayan subregion, W. Pacific and West coast of N. America. In the Indo-Malayan subregion this species is one of the prevailing Pheidole species in semiurban and rural areas. (Eguchi 2008)

Distribution based on Regional Taxon Lists
Australasian Region: New Caledonia. Indo-Australian Region: Borneo, Cook Islands, Fiji, French Polynesia, Guam, Indonesia, Kiribati, Krakatau Islands, Malaysia, Marshall Islands, Micronesia (Federated States of), Northern Mariana Islands, Palau, Philippines, Pitcairn, Samoa , Singapore , Tokelau, Tonga, Vanuatu. Malagasy Region: Mauritius. Nearctic Region: United States. Oriental Region: India, Taiwan , Thailand, Vietnam. Palaearctic Region: China, Japan.

Nomenclature

 *  fervens. Pheidole fervens Smith, F. 1858b: 176 (s.) SINGAPORE. Ogata, 1982: 197 (m.). Senior synonym of cavannae, javana, nigriscapa and material of the unavailable name tahitiana referred here: Wilson & Taylor, 1967: 45; senior synonym of desucta: Eguchi, 2001b: 53; of amia, azumai, dharmsalana, dolenda, pungens, soror: Eguchi, 2004: 197. Current subspecies: nominal plus pectinata.
 * pungens. Solenopsis pungens Smith, F. 1861b: 48 (s.w.) INDONESIA (Sulawesi). Combination in Pheidologeton: Donisthorpe, 1932c: 469; in Pheidole: Bolton, 1995b: 328. Junior synonym of fervens: Eguchi, 2004: 198.
 * javana. Pheidole javana Mayr, 1867a: 98 (s.w.) INDONESIA (Java). Viehmeyer, 1916a: 121 (q.m.). Junior synonym of fervens: Wilson & Taylor, 1967: 45.
 * cavannae. Pheidole cavannae Emery, 1887b: 464 (footnote) (s.) NEW CALEDONIA. Subspecies of oceanica: Emery, 1914f: 401. Junior synonym of fervens: Wilson & Taylor, 1967: 45.
 * dharmsalana. Pheidole javana var. dharmsalana Forel, 1902c: 184 (s.), 198 (w.) INDIA. [Also described as new by Forel, 1902f: 546.] Subspecies of fervens: Bolton, 1995b: 320. Junior synonym of fervens: Eguchi, 2004: 198.
 * amia. Pheidole amia Forel, 1912a: 60 (s.w.) TAIWAN. Junior synonym of fervens: Eguchi, 2004: 197.
 * dolenda. Pheidole javana var. dolenda Forel, 1912a: 60 (s.w.) TAIWAN. Subspecies of fervens: Bolton, 1995b: 320. Junior synonym of fervens: Eguchi, 2004: 198.
 * nigriscapa. Pheidole (Pheidole) oceanica var. nigriscapa Santschi, 1928a: 48, fig. 3 (s.w.) SAMOA. Junior synonym of fervens: Wilson & Taylor, 1967: 45.
 * desucta. Pheidole javana var. desucta Wheeler, W.M. 1929f: 2 (s.w.q.) CHINA. Subspecies of fervens: Bolton, 1995b: 320. Junior synonym of fervens: Eguchi, 2001b: 53.
 * soror. Pheidole javana st. soror Santschi, 1937h: 369, fig. 6 (s.w.) TAIWAN. Subspecies of fervens: Bolton, 1995b: 330. Junior synonym of fervens: Eguchi, 2004: 198.
 * azumai. Pheidole nodus st. azumai Santschi, 1941: 274, fig. 1 (s.w.) JAPAN. Junior synonym of fervens: Eguchi, 2004: 198.

Type Material


Solenopsis pungens

Two syntype major workers and one syntype minor worker (on separate cards) in. Each major worker labelled “Menado” and with a Smith det. label “Solenopsis pungens Smith.” The minor worker with “Men. 18” and an attached note explaining that Pheidole pungens was placed in Solenopsis by an oversight. Each of the three cards has the letter “c” in the lower left corner.

Worker
Eguchi (2008) - Major (n=5). — HL 1.31–1.56 mm; HW 1.22–1.44 mm; CI 92–97; SL 0.84–0.95 mm; SI 66–70; FL 1.12–1.27 mm; FI 88–94. Minor (n=5). — HL 0.65–0.73 mm; HW 0.54–0.60 mm; CI 81–84; SL 0.77–0.87 mm; SI 138–153; FL 0.81–0.93 mm; FI 149–163.

Major — Head in lateral view not or hardly impressed on vertex; posterior concavity of head in full-face view usually shallow; frons and anterior part of vertex rugose longitudinally; posterior part of vertex and dorsal face of vertexal lobe rugoso-reticulate, with interspaces weakly punctured; frontal carina conspicuous; antennal scrobe inconspicuous or shallowly impressed; clypeus without a median longitudinal carina; median and submedian processes of hypostoma absent or present but inconspicuous; lateral processes conspicuous; antenna with a 3-segmented club; maximal diameter of eye almost as long as or shorter than antennal segment X. Promesonotal dome in dorsal view largely smooth, or sparsely sculptured with weak transverse rugulae, in lateral view with a low to conspicuous mound on its posterior slope; humerus not produced; the dome much narrower at the humeri than at the bottom; mesopleuron, metapleuron and lateral face of propodeum well punctured, sometimes overlain with weak rugulae; propodeal spine narrowly based, usually slightly curved apically. Petiole longer than postpetiole (excluding helcium); postpetiole not massive. First gastral tergite smooth and shining entirely, or sometimes shagreened around its articulation with postpetiole.

Minor — Frons and vertex smooth and shining, or rarely shagreened or very weakly rugoso-punctate; area between antennal insertion and eye weakly rugoso-punctate; preoccipital carina conspicuous dorsally and laterally; median part of clypeus smooth, without a median longitudinal carina; antenna with a 3-segmented club; scape extending far beyond posterolateral margin of head; maximal diameter of eye much shorter than antennal segment X. Promesonotal dome largely smooth and shining, but sometimes weakly rugoso-punctate dorsolaterally, in lateral view with a low or inconspicuous mound on its gentle posterior slope; humerus of the dome in dorsal-oblique view not produced; mesopleuron, metapleuron and lateral face of propodeum well punctured; propodeal spine elongate-triangular, directing upward. Petiole (a little) longer than postpetiole (excluding helcium); postpetiole not massive.