Cardiocondyla emeryi

A tramp species common in anthropogenic habits in many tropical regions it nonetheless is an inconspicuous and little noticed ant.

Identification
Seifert (2003) includes a key to the holoarctic species of Cardiocondyla where he also states: "The cosmopolitan population of Cardiocondyla emeryi shows extreme polymorphism in microsculpture clearly exceeding the usual intraspecific variability known for Cardiocondyla."

Distribution
A tramp species that is common in many tropical regions of the world.

This taxon was described from British Virgin Islands. It is also found in New Caledonia, Australia, Norfolk Island, Ecuador, Brazil, Mexico, Honduras, Costa Rica, United States, Dominican Republic, Puerto Rico, Greater Antilles, Lesser Antilles, Bermuda, Bahamas, South Africa, Israel, Kenya, Tanzania, Comoros, Uganda, Zimbabwe, Seychelles, Mauritius, Madagascar, Angola, Cameroon, Sudan, Botswana, Ghana, Nigeria, Saint Helena, Viet Nam, Saudi Arabia, United Arab Emirates ,Spain, Fiji, Samoa, Tonga, Niue, Barbados, Anguilla, Canary Islands, Wallis and Futuna Islands.

Nomenclature

 *  emeryi. Cardiocondyla emeryi Forel, 1881: 5 (w.) VIRGIN IS. André, 1881b: 69 (m.); Forel, 1904f: 422 (q.); Emery, 1909a: 26 (m. ergatoid m., not q.); Arnold, 1916: 201 (q.). Senior synonym of nereis: Wilson & Taylor, 1967: 53; of monilicornis: Baroni Urbani, 1973: 200; of mahdii, mauritia, rasalamae: Bolton, 1982: 312. See also: Smith, M.R. 1944a: 33; Kugler, J. 1984: 3; Seifert, 2003a: 276. Current subspecies: nominal plus fezzanensis.
 * rasalamae. Cardiocondyla emeryi var. rasalamae Forel, 1891b: 161 (w.) MADAGASCAR. Forel, 1912k: 163 (q.). Junior synonym of emeryi: Bolton, 1982: 312.
 * mahdii. Cardiocondyla emeryi subsp. mahdii Karavaiev, 1911: 8 (w.) SUDAN. Finzi, 1936: 169 (q.m.). Junior synonym of emeryi: Bolton, 1982: 312.
 * monilicornis. Xenometra monilicornis Emery, 1917a: 96 (ergatoid m., not q.) VIRGIN IS. Junior synonym of emeryi: Baroni Urbani, 1973: 200.
 * nereis. Cardiocondyla nuda subsp. nereis Wheeler, W.M. 1927i: 140 (w.q.) AUSTRALIA. Junior synonym of emeryi: Wilson & Taylor, 1967: 53.
 * mauritia. Cardiocondyla mauritia Donisthorpe, 1946c: 776 (w.) MAURITIUS. Junior synonym of emeryi: Bolton, 1982: 312.

Worker
Seifert (2003) - Small size, CS 411. Head elongated, CL/CW 1.229. Scape short, SL/CS 0.758. Postocular index large, PoOc/CL 0.467. Eyes medium-sized, EYE 0.246. Frons very narrow, FRS/CS 0.215, frontal carinae immediately behind FRS level slightly converging and then diverging. Occipital margin more or less straight, with a suggested concavity. Whole head and mesosoma without longitudinal rugosity, except for small patches with weak carinulae mentioned below. Anterior clypeal margin with weak median concavity; central surface of clypeus in type specimens of C. emeryi with suggestions of flat foveolae, in type specimens of C. emeryi var. rasalamae with fine, interrupted fragments of carinulae and without any foveolae. Vertex in types of C. emeryi with deeply impressed, flat-bottomed foveolae of 17 - 19 µm diameter in densely-packed honey-comb arrangement; foveolae showing an inner corona (tubercle) of 8 -9 µm diameter (Fig. 58); median vertex with weak, interrupted longitudinal carinulae. Vertex in types of C. e. var. rasalamae in overall impression rather shining, structure and strength of sculpture radically different from that in types of C. emeryi (Fig. 59), showing shallow, but well-demarcated foveolae of 14 - 17 µm diameter, which occasionally possess an inner corona (tubercle); interspaces about as wide as foveolar diameter, much shining, with very fine cross-branched microcarinulae that may completely surround foveolae (= perifoveolar reticulum). Whole surface of mesosoma in types of C. emeryi with well-pronounced and dense microreticulum with meshes of 9 - 12 µm diameter; dorsal mesosoma additionally with scattered foveolae. Dorsal area of mesosoma in the types of C. emeryi var. rasalamae much less deeply sculptured than in C. emeryi types, moderately shining, with shallow foveolae similar to those on vertex; lateral area of mesosoma entirely reticulate but more delicately than in C. emeryi types. Petiole, except for the more smooth dorsal surface with well-pronounced and dense microreticulum that is weaker the C. emeryi var. rasalamae types. Postpetiole more smooth, with finer reticulum. Promesonotal dorsum showing in profile a continuous shallow convexity, not abruptly sloping into the moderately deep metanotal groove. In C. emeryi types, anterodorsal profile of propodeum convex, caudodorsal profile linear and slightly sloping downwards, spines deviating from longitudinal mesosomal axis by 40°. In C. e. var. rasalamae types, whole dorsal profile of propodeum very shallowly convex, not sloping downwards, spines less erect. Petiole node in dorsal view distinctly longer than wide; petiolar peduncle moderately long. Postpetiole in dorsal view wider than long, with shallowly concave anterior margin and evenly convex sides; postpetiolar sternite showing a conspicuous anteroventral prominence or bulge, without dents or carinae (Fig. 6). Different colour variants known: in most frequent variant whole body yellowish except for blackish gaster and terminal segment of antennal club; sometimes whole body dark or dirty brown. For morphometric data of 115 workers see Tab. 13.

Queen
Seifert (2003) - Very small size. Head elongated, CL/CW 1.180. Scape very short, SL/CS 0.731. Postocular index large, PoOc/CL 0.448. Occipital margin more or less straight. Anteromedian clypeal margin between level of frontal carinae straight to slightly concave. Frons very narrow, FRS/CS 0.216, frontal carinae in posterior part almost parallel. Vertex in the emeryi morph with deeply impressed, flat-bottomed foveolae of 16 - 17 µm diameter in densely-packed arrangement, foveolae showing an inner tubercle of 8 - 9 µm diameter; vertex sculpture in the rasalamae morph similar, but foveolar diameter a little smaller and arrangement less dense. Clypeus and narrow median stripe of anterior vertex frequently with short fragments of weak carinulae. Whole mesosoma without elements of longitudinal sculpture, except for 4 - 6 weak longitudinal carinae on lateral area of metapleuron. Whole dorsal area of mesosoma with deep, densely-packed foveolae; in the rasalamae morph foveolae less deep. Lateral area of mesosoma and petiolar peduncle reticulate. Petiole node foveolate, in dorsal view longer than wide, axis of petiolar peduncle deviating in lateral view from petiolar node axis by 45°. Spines well-developed, their axis deviating in lateral view by 18 - 30° from longitudinal mesosomal axis. Postpetiole with a strong anteroventral bulge, in dorsal view wider than long, with strongly convex sides, slightly concave anterior margin, and foveolate. Gaster tergites shining, but with very fine microreticulum. Colour bimorphism. Light form: lateral area of mesosoma, waist, and appendages yellowish; scutellum, gaster, and antennal club dark brown; remaining body parts yellowish brown. Dark form: whole body dark brown; coxae, femora, tibiae, scape, base of funiculus, and ventrolateral area of pronotum yellowish. For morphometric data of 12 gynes see Tab. 19.

Male
Andre (1881) described a male of the synonymous C. elegans and Emery (1909) described a C. emeryi ergatoid male.

Type Material
Seifert (2003) lists the following type material that he examined:

Cardiocondyla emeryi: 2 syntype workers labelled by Forel "Cardiocondyla Emeryi Forel Antilles St. Thomas (Forel)", MHN Genève.

C. emeryi var. rasalamae: 2 syntype workers labelled by Forel "C. emeryi Forel v. rasalamae Forel, Antananarivo Camboúe", MHN Genève. 1 syntype worker labelled by Forel "C. emeryi Forel v. rasalamae Forel, Antananarivo (Camboúe)" and by G. Mayr "Emeryi v. rasalamae Forel, Type", NHM Wien.

C. emeryi ssp. mahdii: 3 syntype workers labelled by Karavajev "Cardiocondyla mahdii sp.n. Karaw., Khartum 1900 W.K.", MHN Genève and NHM Basel.

C. nuda ssp. nereis: 4 syntype workers and 3 syntype gynes labelled "Norfolk I, A.M. Lea\Wm.M. Wheeler\M.C.Z. CoType 27887\subsp. nereis Wheeler", MCZ Cambridge.

C. mauritia: 1 type worker labelled "Mauritius 1941-45, 102, R. Mamel", "Pres. by Imp. Inst. Ent. B. M.1947-128", "Cardiocondyla mauritia H. Donisthorpe 1945 TYPE", BMNH London.

Additional References

 * Seifert, B. 2003. The ant genus Cardiocondyla (Insecta: Hymenoptera: Formicidae) - A taxonomic revision of the C. elegans, C. bulgarica, C. batessi, C. nuda, C. shuckardi, C. stambuloffi, C. wroughtoni, C. emeryi, and C. minutior species groups. Ann. Naturhist. Mus. Wien Ser. B. Bot. Zool. 104:203-338.


 * Wetterer, J. 2012. Worldwide spread of Emery's sneaking ant, Cardiocondyla emeryi (Hymenoptera: Formicidae). Myrmecological News, 17, 13-20.