Des soldats de Ziela, Keoulenta, 6 [[queen]] ailees et 10 ouvrieres du Mont To a 1.600 m., sont laisses de cote provisoirement. Ils sont peut-etre nouveaux, mais ni la bibliographie ni les collections suisses consultees n'apportent de certitude a cet egard, tant la systematique du genre est incertaine.
Pheidole , Westw. Ann. & Mag. Nat. Hist. vi. 8/ (1841). Oecophthora , Heer, Ueber die Hausameise Madeir. (1852).
Head large in the worker major, of moderate size in the other sexes. Mandibles very strong, the inner edge oblique, without teeth in the large worker, toothed in the small worker. Maxil- lary palpi 2-jointed; labial palpi 2-jointed. Antennae 12-jointed in the females, large and small workers. Thorax narrower than the head, much more so in the large workers. Wings with two complete submarginal cells, and one complete discoidal cell; the metathorax usually with two short spines. The anterior tibias in the females, large and small workers, with a pectinate spine at their apex.
We have compared numerous examples of Oecophthora with specimens of Pheidole providens , and cannot find the differences mentioned by Professor Heer; there is no difference in the relative length of the first joint of the tarsus; the mandibles are equally acute at their apex; in all generic characters they pre- cisely correspond. We have not seen the males of either of the types, but as other sexes agree in every particular, we have in- cluded in one genus all such species as possess the characters above given.
Taxonomy. The genus Pheidole is placed in the tribe Pheidolini (for its complete taxonomic history see Bolton (2003) and Bolton et al. (2006)). North Vietnamese species of the genus were recently revised and 31 species were recognized by Eguchi (2008). Workers of Vietnamese species have the following features.
Worker dimorphic; major with head in full-face view subrectangular, subtrapezoidal or cordate, with posterolateral corner developed as preoccipital lobe; minor with head in full-face view oval, elliptical or subrectangular;frontal lobes far apart so that posteromedian portion of clypeus, where it projects between frontal lobes, is usually broader than one of the lobes; midpoint of anterior clypeal margin without an unpaired median seta; mandible of major massive, with 2 large apical and 1 or 2 conspicuous basal teeth, and margin between these groups of teeth edentate or irregularly and bluntly crenulate; mandible of minor triangular; masticatory margin with 7 or more teeth/denticles; 1 or 2 small denticles present between preapical tooth and 3rd large tooth; in major hypostoma always bearing a large or reduced "lateral" process just mesal to each mandibular base, and often bearing a "median" process and/or a pair of "submedian" processes, i.e. middle of hypostoma bearing 0-3 processes; palp formula 2,2; antenna 12-segmented, with 3- or 4-segmented club, or without a conspicuous club (3-segmented club the dominant condition); eye always present but varying in size, rarely consisting of only a few ommatidia; promesonotum forming a dome which is well raised above level of dorsum of propodeum; promesonotal suture absent or indistinct dorsally; posterior slope of promesonotal dome sometimes with a mound or prominence; metanotal groove weakly to strongly impressed dorsally; propodeal spine usually present (rarely vestigial or almost absent), and variable in size and shape; propodeal lobe inconspicuous, or present as a low lamella, or moderately roundly expanded; petiole in lateral view consisting of slender anterior peduncle and raised posterior node, or petiole gradually rising from base to summit of node; postpetiole in lateral view hemispherical, globular or highly domed, sometimes with anteroventral angle or projection.
The minor worker of Pheidole is similar to the worker of Aphaenogaster (for distinguishing characters see under Aphaenogaster ), Kartidris and Lophomyrmex (see under Lophomyrmex ). However, in the worker of Kartidris , the masticatory margin of the mandible bears 5 sharp teeth which decrease in size from the apex to the base, and a broad depressed area is present on the vertex between the eyes.
Vietnamese species. Forty-two species have been recognized by us from Vietnam: aspidata Eguchi & Bui (Nam Cat Tien); binghamii Forel (Binh Chau-Phuoc Buu, Nam Cat Tien, Phu Quoc); capellinii Emery (Ba Vi, Nam Cat Tien); colpigaleata Eguchi (Ba Vi, Sa Pa, Tay Yen Tu); dugasi Forel (Ba Vi, Cuc Phuong, Nam Cat Tien); elongicephala Eguchi (Ba Vi, Cuc Phuong, My Yen, Tay Yen Tu, Van Ban); fervens F. Smith (Ha Noi, My Yen, Nui Chua); fervida F. S m i t h (Sa Pa); fortis Eguchi (Sa Pa, Tam Dao); foveolata Eguchi (Sa Pa); gatesi (Wheeler) (Ba Vi, Cuc Phuong, Tam Dao); hongkongensis Wheeler (Ba Be, My Yen, Pu Mat, Tam Dao, Tay Yen Tu, Van Ban); indosinensis Wheeler (Ba Vi, Tam Dao); laevicolor Eguchi (Ba Be, Ba Vi, Chua Yen Tu, My Yen, Tay Yen Tu, Van Ban); laevithorax Eguchi (Ba Vi, Chua Yen Tu, Tay Yen Tu); magna Eguchi (Ba Vi, Sa Pa); megacephala (Fabricius) (Ha Noi, Quang Ninh, Vinh Long); noda F. Smith (Ba Be, Ba Vi, Chua Yen Tu, Cuc Phuong, Sa Pa, Tam Dao, Van Ban); ochracea Eguchi (Ba Vi, Nam Cat Tien, Sa Pa, Tam Dao, Tay Yen Tu); parva Mayr (Cuc Phuong, Ho Chi Minh City, My Yen); pieli Santschi (Ba Be, Ba Vi, Chua Yen Tu, Cuc Phuong, Hoa Binh, Ky Thuong, Phu Quoc, Pu Hoat, Pu Mat, Tam Dao, Tay Yen Tu, Van Ban); plagiaria F. S m i t h (Ba Vi, My Yen, Tam Dao, Phu Quoc); planidorsum Eguchi (Nam Cat Tien); planifrons Santschi (Nam Cat Tien, Pu Mat, Tam Dao, Tay Yen Tu, Van Ban); rabo Forel (Ba Vi, Chua Yen Tu, Cuc Phuong, Ky Thuong, Nam Cat Tien, Phu Quoc, Pu Mat, Tay Yen Tu, Van Ban); rinae Emery (Nam Cat Tien); rugithorax Eguchi (Pu Mat, Nam Cat Tien, Nui Chua, Phu Quoc); smythiesii Forel (Ba Vi, Pu Hoat, Tam Dao); taipoana Wheeler (Ky Thuong, Pu Mat); tandjongensis Forel (Phu Quoc); tjibodana Forel (Ba Be, Chua Yen Tu, Cuc Phuong, Nam Cat Tien, Ky Thuong, Pu Mat, Tay Yen Tu, V a n B a n); tumida Eguchi (Ba Be, Ba Vi, Chua Yen Tu, Cuc Phuong, Ky Thuong, Nam Cat Tien, Nui Chua, Pu Mat, Tay Yen Tu; Van Ban); vieti Eguchi (Ba Vi, Tam Dao); vulgaris Eguchi (Ba Vi, Chua Yen Tu, Cuc Phuong, Ky Thuong, My Yen, Sa Pa, Tam Dao, Tay Yen Tu); yeensis Forel (Ba Be, Ba Vi, Cuc Phuong, Ky Thuong, My Yen, Nam Cat Tien, Pu Hoat, Pu Mat, Tam Dao, Tay Yen Tu); zoceana Santschi (Pu Hoat, Sa Pa); sp. eg-165 (Lam Dong); sp. eg-170 (Nam Cat Tien); sp. eg-179 (Nam Cat Tien); sp. eg-187 (Nui Chua); sp. eg-188 (Van Ban); sp. eg-189 (Nui Chua).
Bionomics. Pheidole inhabits various habitats such as bare lands, grasslands, forest edges and well-developed forests. Their nests are usually found in rotting logs, twigs, wood fragments, under stones and in soil. The majority of species forage on the ground, but some such as P. v u lg a r is forage both on and under the ground.
Boquerón (ALWC).
Canindeyú , Cordillera, San Pedro (ALWC, INBP, LACM).
Canindeyú . (ALWC, LACM).
Concepción , Central (ALWC).
Canindeyú (ALWC, LACM).
Amambay, Canindeyú (ALWC).
Alto Paraná (ALWC, BMNH).
Central, Itapúa (ALWC).
Canindeyú (ALWC, INBP).
Boquerón , Pte. Hayes (ALWC).
Canindeyú (ALWC).
Canindeyú , Central (ALWC).
Canindeyú , Central (ALWC).
Central (ALWC).
Itapúa , Misiones (ALWC).
Canindeyú , Itapúa (ALWC, BMNH, MHNG).
Boquerón , Central, Itapúa (ALWC).
Central, Cordillera, Itapúa , Pte. Hayes (ALWC, INBP, MCZC).
This is one of the world’s largest ant genera, with more than 600 species recognized in the New World alone (Wilson 2003). The native California Pheidole are all ground-dwelling species, found in open, dry habitats. A few of the species are generalized scavengers, but most belong to a group of seed-harvesting specialists, the P. pilifera-group , with fifteen species in the state. There are also three introduced species, currently of limited distribution and confined to urban areas.
Species identification: keys in Gregg (1959), Wheeler and Wheeler (1986g) and Wilson(2003). Additional references: Clark et al. (1986), Cole (1956c), Creighton and Gregg (1955), Davidson (1977a), Johnson (2000a, 2000b, 2001), Langen et al. (2000), Martinez (1992, 1996, 1997), Snelling (1992b), Snelling and George (1979), Ward (2000), Wheeler and Wheeler (1973e).
Small ants with the worker strongly dimorphic, the two forms being designated as the worker and soldier. In a few species these phases are connected by intermediates(mediae).
Soldier with very large head, subrectangular or subcordate, more or less deeply notched or excised behind and with a distinct occipital furrow, on each side of which the occipital region is convex. Clypeus short, depressed, carinate or ecarinate but not elevated in the middle, the anterior border entire or notched in the middle, the posterior border extending back between the frontal carinae, which vary in length, being short in some species and in others greatly prolonged backward and forming the inner borders of more or less distinct scrobes for the antennae. Frontal area usually distinct, deeply impressed. Mandibles large, convex, usually with two apical and two basal teeth, separated by a toothless diastema. Antennae 12-jointed; the funiculus with long first joint; joints 2 to 8 small and narrow; the three terminal joints forming a well-developed club. Thorax small, usually with distinct promesonotal and mesoepinotal sutures and pronounced mesoepinotal constriction; the pro- and mesonotum raised, more or less convex, the humeri sometimes prominent, the mesonotum often with a transverse welt or torus; the metanotum sometimes represented by a distinct sclerite; the epinotum armed with spines or teeth, in profile with distinct basal and declivous outline. Petiole small and narrow, pedunculate anteriorly, the node posterior, compressed anteroposteriorly, its superior border sometimes emarginate, the ventral surface unarmed. Postpetiole broader than the petiole, convex and rounded above, contracted behind, the sides often produced as angles or conules, more rarely as spines. Gaster rather small, broadly elliptical or subcircular. Femora more or less thickened in the middle; middle and hind tibiae without spurs; tarsal claws simple.
Worker smaller than the soldier but very similar in the structure of the thorax, pedicel, and gaster; the head, however, much smaller, not grooved nor deeply excised posteriorly; the antennae longer; the mandibles less convex, with evenly denticulate apical borders. The pro- and mesonotum are proportionally less convex, and the petiole and postpetiole are more slender.
Female resembling the soldier but larger; the head proportionally smaller and shorter, usually not longer than broad and not broader than the thorax; the occiput only broadly and feebly excised. Thorax broad and massive; the mesonotum flat, overarching the pronotum in front. Epinotal spines shorter and stouter; petiole and postpetiole more massive; gaster much larger and more elongate than in the soldier. Wings long, with a discoidal cell, two closed cubital cells, and an open radial cell.
Male decidedly smaller and more slender than the female, the head small, with large, convex eyes and ocelli; mandibles small but dentate. Clypeus longer than in the soldier. Antennae 13-jointed; the scapes very short, scarcely longer than the second Funicular joint, first joint sub globular. Thorax broad; the mesonotum flattened, without Mayrian furrows, anteriorly overarching the small pronotum; epinotum unarmed. Petiole and postpetiole slender, with low nodes. Gaster slender, elongate. Genital appendages small. Cerci present. Legs long and slender. Wing venation as in the female.
Map 20. Distribution of the genus Pheidole .
Nearly all the species of Pheidole nest in the ground, either under stones and logs or in crater or small mound nests. Many species feed exclusively on insects and often have a peculiar fecal odor precisely like that of the Dorylinae, which also have an insect diet; but many species are harvesters and store the chambers of their nests with the seeds of small herbaceous plants. This is especially true of the desert species of Pheidole . In some species in Australia and the southern United States, the soldiers take on the function of repletes and store in their crops sweet liquid for the use of the colony during periods of food and water scarcity. One species, Pheidole megacephala , has been carried to all parts of the tropics and has become a great pest in and about dwellings and plantations as it assiduously cultivates coccids on many economic plants and ruthlessly destroys and replaces the native ant-faunas. This has been observed in the Madeira Islands, Hawaii, Australia, and the West Indies. In all probability P. megacephala is of Ethiopian or Malagasy origin, as it shows a great development of subspecies and varieties in these two regions and nowhere else.
Oecodoma malabarica, Jerdon , Madr. Journ. Lit. & Sc. 107 (1851); Ann. & Mag. Nat. Hist, ser. 2. xiii. 49 (1854).
Hab. India.
Une [[queen]] desailee, peut-etre nouvelle, mais sans certitude, car les reines des petits Pheidole sont tres peu decrites. Ziela, savane (LaMOTTE). Se placerait entre corticicola SANT., (espece commune au Banco) et decarinata SANT. du Soudan. A revoir quand les ouvrieres seront prises. Cette Fourmi est remarquablement petite pour une reine (4 mm. 8).
Pheidole is a genus of ants that belongs to the ant subfamily Myrmicinae. The genus is widespread and ecologically dominant. It probably includes more than 1000 species.[1] The genus first evolved in the Americas, eventually spreading across the globe.
Most species of Pheidole are dimorphic, which means that colonies contain two castes of workers, the "minor" workers, and the "major" workers, or "soldiers". The latter generally have much larger heads and mandibles in comparison to their usually fairly modest body size. [2]
In addition, as in other ant species, a colony may contain one or several queens, and also in mature colonies, alates - virgin winged females and males.
major and minor workers of P. xerophila
The distinctive major workers have earned the genus Pheidole the nickname of "big-headed ants". The major workers of a Pheidole colony, while they may look fierce, are often quite shy and are often the first to flee on any hint of danger. Many Pheidole species are the prey of parasitoid phorid flies that lay their eggs on the major workers; the fly larvae grow mainly in the head capsules of the victims, eventually decapitating them, and probably would starve in the bodies of minor workers.
In most cases, the major workers are employed within the nest to break up large food items, or outside to carry large items, such as seeds; many Pheidole species are ecologically important seed consumers ("harvesters").
Minor worker
Minor worker, top
Major worker
Major worker, top
The genus contains over 1,000 species.[3] They include:
Pheidole is a genus of ants that belongs to the ant subfamily Myrmicinae. The genus is widespread and ecologically dominant. It probably includes more than 1000 species. The genus first evolved in the Americas, eventually spreading across the globe.
Pheidole mendicula
