|The Ants of
SUBFAMILY MYRMICINAE - Genus Cardiocondyla
|Contents - Myrmicinae - MYRMICINAE Introduction|
In Tribe FORMICOXENINI.
Diagnostic Features - Eyes well developed and sited forward of the front of the midlength of the head. Antennae 12-segmented, with a three-segmented club, and the scapes short, failing to reach the posterior margin of the head. The lateral portions of the clypeus project forwards over the basal margins of the mandibles. Sculpture usually of fine dense puncturation on the head and alitrunk, but none on the gaster. Sparse pubescence but erect setae only on the anterior clypeal margin. Alitrunk with the promesonotal suture absent and the metanotal groove impressed. Propodeum with a pair of teeth or spines. Petiole with a long peduncle in front; in dorsal view the post-petiole is very broad. Middle and hind tibiae without spurs.
Emery's (1869b) genus description is at . Arnold (1916) gave a genus description, this is at .
Revised by Bolton (1982). All small to minute ants which nest in
soil, usually at the bases of trees, or in compressed leaf litter.
Belshaw & Bolton (1994) noted that three species are known from
Ghana. The full text of Bolton's revision can be seen at -
Bolton, B. 1982. Afrotropical species of the myrmicine ant genera Cardiocondyla, Leptothorax, Melissotarsus, Messor and Cataulacus (Formicidae). Bull. Brit. Mus. (Nat. Hist.) Entomol. 45: 307-370. View or download entire file (7.6M) .
Rigato (2002) described three new species from sub-Saharan Africa. Two, longinoda and luciae were from Tanzania and one, yorubae, came from Nigeria. The latter however, seems to differ little from emery. Moreover, it exactly matches the specimen I drew from Nigeria and collected at some time by Barry Bolton. Rigato, who was supplied with the specimens he described by Bolton, makes no mention of sighting either emery from any other source. I, therefore, tentatively regard yorubae as a junior synonym of emeryi.
In contrast to Rigato, Seifert (2003) made an extremely detailed and sophisticated study of primarily Holarctic Cardiocondyla. Although published later, this study surely, at least, overlaps that by Rigato. Seifert included all but two of the species in Bolton (1982) and transferred globinodis and badonei from wroughtoni to venustula. The latter thus was added to the list from sub-Saharan Africa, as is C. mauritanica (a Zimbabwe record)
Key to species known from Africa (derived from Bolton, 1982, and revised to incorporate Rigato, 2002):
|¤||Queen only known; dark brown to blackish brown||Nigeria - zoserka|
|1||Alitrunk dorsum without metanotal groove or impression; propodeum unarmed; TL 2.7 mm; yellow with silvery pubescence||.|
|.||Angola - monardi|
|--||Alitrunk dorsum with distinct metanotal groove; propodeum sharply angulate or bispinose||2|
|2||In full face view scapes distinctly exceeding occipital margin; TL 2.5 mm; bright ferruginous||Sudan - as a junior synonym of fajumensis - nilotica|
|--||Scapes not exceeding occipital margin||3|
|3||Dorsal surfaces of head and alitrunk smooth and glossy, unsculptured except for minute puncturation on head; TL 1.8 mm; uniform glossy blackish brown||Ghana - sekhemka|
|--||Dorsal surfaces of head, alitrunk or both finely and densely sculptured||4|
|4||Dorsum of gaster distinctly finely shagreened, not smoother than head or alitrunk||5|
|--||Dorsum of gaster not shagreened, smoother than head or alitrunk||6|
|5||Petiole with elongate node, 1.5 X longer than wide, with a low profile; TL 2.1 mm; scape relatively long SI 97-100; testaceous yellow||.|
|.||.||Tanzania - longinoda|
|--||Petiole with shorter node, less than 1.5 X longer than wide, with a domed profile; TL 2.1 mm; scape relatively long SI 90; reddish brown, gaster duller, antennal club darker||.|
|.||Tanzania - luciae|
|6||Propodeum in absolute profile bluntly angulate to bidenticulate, never with a pair of strong teeth or spines which are longer than their basal width in profile; scapes relatively long; TL 2.0-2.6 mm; medium brown to blackish-brown||Pan-African - shuckardi|
|--||Propodeum in profile strongly bidentate to bispinose; scapes relatively short||7|
|7||In profile alitrunk with propodeal dorsum approximately flat behind the propodeal groove, more or less level with the promesonotal dorsum, and not sloping gradually down to the spines; TL 1.9 mm; alitrunk medium-brown, appendages lighter, head dorsally and gaster blackish-brown to black||Cameroun - weserka|
|--||Alitrunk dorsum convex behind metanotal groove, then sloping down to spines||8|
|8||In profile alitrunk with sharp drop into metanotal groove; TL 1.6-1.9 mm; head, alitrunk and appendages yellow to yellowish brown but gaster variable from same colour to much darker||Pantropical tramp - wroughtonii|
|In profile alitrunk with even curve into metanotal groove||9|
|9||Pronotal corners bluntly but conspicuously angular in dorsal view; propodeal spines relatively long and slender; TL 1.80-1.81 mm; light brownish yellow; sides of first gastral tergite a rich darker brown||West Africa - neferka|
|--||Pronotal corners rounded in dorsal view, propodeal spines relatively short and stout; TL 1.8 mm; colour orange with gaster and antennal club brown||Pantropical tramp - emeryi (yorubae)|
Key following Seifert (2003); with addition of wasmanni, 2009
Note - this does not include monardi, sekhemka or zoserka from the Bolton paper; nor the Rigato species, longinoda and luciae; yorubae also was too late for Seifert to include but the specimens are among Seifert's emeryi; Seifert synonymised nilotica with fajumensis which replaces it in the sub-saharan Africa list. Seifert's records of specimens he examined have to be questioned, however, as he appears to list the same specimens from Gambari, CRIN, Nigeria, under emeryi and neferka; also he lists a specimen of obscurior from Kaijado, Kenya, but from photographic evidence that seems likely to have been wroughtoni.
CL - HL on median line; CS = median of CW+CL; FRS = distance of frontal carinae immediately caudal of the posterior intersection points betwwen the frontal cariane and the dorsal lamellae of the torus; PPH = maximum postpetiole height; mesosoma used rather than alitrunk. The scale on his illustrations of the main worker is 213 µm.
I find that for a field worker or, indeed, anyone without very high quality equipment, his key as it stands is not easy too use.
|1||Postpetiole with prominent anteroventral corners; seen from a frontal angle the anterior margin is concave||2|
|--||Postpetiole without prominent anteroventral corners||5|
|2||Head short CL/HW < 1.19||3|
|--||Head longer, frons narrower||4|
|3||First and following gaster tergites not equally dark [In profile alitrunk with sharp drop into metanotal groove; TL 1.6-1.9 mm; head, alitrunk and appendages yellow to yellowish brown but gaster variable from same colour to much darker]||cosmopolitan tramp; Tanzania & Somalia - wroughtonii|
|--||First and following gaster tergites equally dark||cosmopolitan tramp but the single Kenya record (worker, Kaijado, x.1999) may be an error - obscurior|
|4||Alitrunk (mesosoma) profile relatively flat, metanotal groove shallow, pronotum with more rounded shoulders [In profile alitrunk with propodeal dorsum approximately flat behind the propodeal groove, more or less level with the promesonotal dorsum, and not sloping gradually down to the spines; TL 1.9 mm; alitrunk medium-brown, appendages lighter, head dorsally and gaster blackish-brown to black]||.|
|.||.||Cameroun - weserka|
|--||Alitrunk (mesosoma) and propodeum profile slightly convex, metanotal groove distinct, pronotum with well-developed shoulders, each with a rounded angle of 120° [Pronotal corners bluntly but conspicuously angular in dorsal view; propodeal spines relatively long and slender; TL 1.80-1.81 mm; light brownish yellow; sides of first gastral tergite a rich darker brown]||.|
|.||West Africa - neferka|
|5||FRS/PPH < 0.722; small CS 386-457 µm; head elongated CL/CW 1.19-1.27; postpetiole as high as petiole with conspicuous ventral bulge; propodeal spines moderately long||widespread tramp - emeryi|
|.||dark form apparently common in Congo Basin||emeryi|
|--||FRS/PPH > 0.722||6|
|6||Propodeal spines in lateral view with blunt angles of 95-120°; sides of postpetiole in dorsal view always rounded convex; promesonotal and anterior propodeal profiles forming shallowly convex curvatures to give a wide metanotal depression||shuckardi-group - 7|
|--||Propodeal spines in lateral view with smaller angles of 60-95°; sides of postpetiole in dorsal view more angular; promesonotal and anterior propodeal profiles not forming shallowly convex curvatures, so metanotal depression weak or absent||Zimbabwe (once; gyne only, vii.1995) - nuda-group - mauritanica|
|7||Scape relatively short SL/CS 0.79-0.84; postpetiole wider; metanotal depression shallower; unicolorous medium to dark brown||southern East Africa - shuckardi|
|7a||Generally more heavily built and with much more distinct sculpturation on the head and alitrunk; also metanotal impression quite deeply impressed both dorsally and laterally||West Africa and Congo Basin East Africa - wassmanni|
|--||Scape longer SL/CS 0.81-0.87; postpetiole narrower; metanotal depression deeper||8|
|8||Eye larger; all over dark brown, smaller CS 467-572 µm||south-eastern Africa - venustula|
|--||Eye smaller; head and alitrunk variably yellowish, gaster dark to blackish-brown, larger CS 556-633 µm||Sudan (as nilotica) - fajumensis|
© 2007, 2009, 2013, 2014, 2019 - Brian Taylor CBiol FRSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.