|The Ants of
SUBFAMILY PONERINAE - Genus Ponera
|Contents - Ponerinae - PONERINAE Introduction|
In Tribe PONERINI.
Diagnostic Features - Middle and hind tibiae with a single pectinate spur; mandibles unspecialised; integument finely or densely punctate, at least gaster with abundant pubescence; clypeus unarmed; antenna without distinct club; eyes small, sometimes obsolete or absent (from Wheeler, 1922). Note that Bernard (1952) separated two subgenera Ponera and Hypoponera on the basis of the presence of a groove or at least clear suture between the mesonotum and the propodeum in the former, and no more than a dorsally visible suture on the latter. Latreille's (1804) genus definition is at .
Schmidt & Shattuck (2014: Fig. 48) map "exotic" presence of unnamed Genus Ponera
Latreille, in Gabon and South Africa but cite Bolton & Fisher (2011) as reporting no definitive records. Antweb - see http://www.antweb.org/specimenImages.do?code=casent0900367 (accessed 27.vi.2014) show a worker of Ponera swezeyi from Zanzibar but no Ponera from Gabon or South Africa. Although the presence of P. swezeyi
is remarkable, given that the only prior locations are Hawaii and
Samoa, Zanzibar is a port and the worker does appear very close to the
The most recent Genus revision is that of R. W. Taylor (1967) but presently, I find the present situation somewhat confusing. Bolton (1995) provided an extensively revised list for Ponera and Hypoponera with a number denotated as a "new combination" but in many cases the justification is neither given nor indicated. At the genus level, by deduction, it seems that the authority lay in work being undertaken by W.L. Brown, or else was an extrapolation from Taylor (1967) - as Bolton (1995, 32, 43, 360) noted Hypoponera "raised to genus" and Ponera "Revision of genus: Taylor, 1967". Ponera he gave as "Holarctic, Oriental, Indo-Australian, Australasian" and listed some 32 extant species, of which all but four are from the Western Pacific rim. The exceptions being P. coarctata (type loc. Luxembourg, plus ssp from southern European and western Asia localities), P. sysphinctoides (type loc. France), P. exotica (type loc. USA) and P. pennsylvanica (type loc. USA). Hypoponera was denoted as "worldwide". Bolton (1973a) wrote how - "true Ponera, as defined by Taylor (1967) does not occur in West Africa", which is curious as Bernard's work (1952) was listed by Bolton.
The key defining character Taylor (1967a: 9) used for separation of Ponera from Hypoponera was the presence in Ponera of a highly characteristic subpetiolar process; usually shallow, with a rounded or bluntly angled anteroventral corner, and a more or less distinctly angled posteroventral one. The latter is composed of 2 separate, small to large, right-angled acute teeth, situated side by side, and sometimes inclined posterolaterally. Anteriorly, the subpetiolar process has a more or less distinct circular or oval thin-spot, or fenestra, visible in transmitted light. This fenestra was noted as never present in Hypoponera.
R W Taylor affirmed Ponera coarctata (shown right) as the type species.
Until recently (2012) specimens sent to me from a recent collection in South Africa appeared to be the first definite record of any true Ponera from sub-Saharan Africa and my photograph of the worker showed the clear spot in the sub-petiolar process. The comprehensive revisionary study of the Afrotropical and West Palearctic members of the genus Hypoponera by Bolton & Fisher (2011) made it possible to re-assess the South African P. coarctata. The species actually is Hypoponera spei (shown right).
Their re-description of H. spei, however, appears to blur the separation of the two genera.
To quote (page 9): 'The pit [in the subpetiolar process] is even more strongly developed in boerorum and spei, where it often appears as a thin spot or fenestra that is reminiscent of the condition universal in Ponera. Coupled with this, in spei the subpetiolar process often has a distinct sharp posteroventral angle, so that in profile the Ponera-like condition becomes even more apparent. This is probably a convergence phenomenon because, unlike Ponera, the Hypoponera species with this fenestra do not have a posteriorly bifurcated ventral surface to the petiole sternite and the posteroventral apex of the subpetiolar process is never produced into a pair of sharp teeth that represent the apices of the bifurcation, such as is universal in genuine Ponera".
This separation of two genera from a single, extremely
difficult to see, character may be sound but Bolton & Fisher offer
no other clear characters and are dismissive of the more obvious
possible separation of Hypoponera
by the presence or absence of a metanotal groove on the alitrunk.
Bolton & Fisher's re-description can be found in http://www.mapress.com/zootaxa/list/2011/2843.html
© 2007, 2008, 2012, 2014 - Brian Taylor CBiol FSB FRES
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