The Ants of
Africa SUBFAMILY PONERINAE - Genus Hypoponera |
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Contents - Ponerinae - PONERINAE Introduction |
In Tribe PONERINI. Diagnostic Features - Santschi (1938b) separated these but as a subgenus on the grounds of the absence (or effaced) of a metanotal suture. Bolton (1994?) Small ants, usually yellowish-brown in colour. Mandibles armed with three or four teeth apically, usually followed by a series of denticulae. Eyes reduced but usually present, close to anterior of head. Sculpture usually of fine dense puncturation. Middle and hind tibiae each with a single pectinate spur. |
Bolton (1973a) described the genus Hypoponera as common in West Africa, being found in leaf-litter and log-mould. Most species feed on collembolans (Lévieux, 1983b). |
At first sight, the present situation is 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 lies in work that was being undertaken by W.L. Brown, or else is an extrapolation from R W 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. Hypoponera was denoted as "worldwide". Bolton (1973a) wrote how - "true Ponera, as defined by Taylor (1967) does not occur in West Africa". Taylor (1969a) also considered the two Cryptopone species, angustata and hartwigi, both belonged in Hypoponera. Whilst Bolton (1995) had the first in Hypoponera, the latter remained in the Genus Cryptopone (the "card" for the species has a hand-written confirmation by W.L. Brown, who had seen the type in 1969, obviously too late for Taylor to know about). |
Hypoponera originally was defined by Santschi (1938b: 79) as a subgenus of Ponera; type species Ponera abeillei. Bernard (1952) recognising Ponera, with Hypoponera as a subgenus, related how Santschi was the first to provide clear descriptions with good illustrations of the workers. Santschi's definition of (subgenus) Hypoponera is at . |
R W Taylor (1967a) decided that this was not valid because the key defining character he 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. His genus separation indicated this posterior angular lobe(s) is never present in Hypoponera. Taylor's (1967a: 9) redefinition of the Genus is at . R W Taylor affirmed Ponera coarctata as the type species of the genus Ponera. The recent collection from South Africa appears to be the first definite record of any true Ponera from sub-Saharan Africa and my photograph of the specimen shows the clear spot in the sub-petiolar process. In 2008 I was sent specimens collected in Gabon that key out to Hypoponera coeca but which have a small distinct clear spot in the anterior subpetiolar process. Taylor remarked that for Hypoponera sensu Santschi included those species of Ponera (s. lat) lacking an incised mesometanotal suture on the mesosomal (alitrunk) dorsum and then stated: "This character, in fact, has no diagnostic value at the generic level" but provided no supporting evidence. Similarly, there is no evidence that Taylor examined any specimens or even source publications on the species from sub-Saharan Africa. It is unclear how many species of "Hypoponera" Taylor actually examined. None are dealt with in his 1967 paper. In Wilson & Taylor (1967) there are four species listed from Polynesia, all have the metanotal suture visible. Taylor (1968) dealt with North American species, again all five have a metanotal suture. None of his other papers deal with them. |
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 Bolton & Fisher (2011: 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". Bolton & Fisher's re-description can be found in http://www.mapress.com/zootaxa/list/2011/2843.html |
My prior thinking based on the situation up to and including Taylor (1968) follows. As is the norm in all his works, Bolton (in this case with
Fisher) has totally ignored, or at least makes no reference at all to
my website nor even to the few specimens collected by me in Nigeria,
e.g. H. cammerunensis depsoited with Bolton in the BMNH and published in Taylor (1976: 21) but not listed by Bolton & Fisher (2011: 34). R W Taylor's works appear to leave Santschi's key character unchallenged but that places the majority of African species, i.e. those with a distinct metanotal suture, in a curious limbo. It also is a mis-match for almost all the non-African species listed as in Hypoponera by Bolton (1995); see also those reported from Costa Rica by Jack Longino http://www.evergreen.edu/ants/genera/hypoponera/key.html; and from Cachoeira, Brazil http://www.ants-cachoeira.de/Ants/Hypoponera/Hypoponera.html. |
In his list Santschi (1938b) has the following as in subgenus Hypoponera
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This listing is clearly wrong in some aspects. For instance, the original description of P. japonica has "distinct promesonotal and mesoepinotal [metanotal] sutures"; Ponera scabra has "distinct promesonotal and indistinct mesoepinotal sutures [neither impressed]". In his key, Emery (1900c: 316) has biroi as with no mesoepinotal suture [although his drawing of the alitrunk profile shows a slight depression where the metanotal suture would be] and papuana with a faint suture; all the others shown in his illustration (right) had both sutures distinct. Taylor (1967: 4) has clavicornis, japonica and scabra in Ponera s.s.. |
Taking the above in combination, in my attempt at a key, I have adopted the term similoponera-group for those with a distinct metanotal suture and reserved hypoponera-group for those with no sign of such a suture. |
To backtrack, Bernard's work appears to be the best available to date on African species (Bernard, 1952, 196-7). He reckoned that 30 species of Ponera had been described from Africa; and wrote how Wheeler (1922) did not cite any Ponera (surmising that the collectors of the American expedition might well have captured specimens but that it had proved too difficult a task to make a publishable analysis). The Mt. Nimba surveys, however, had found 4 known forms and 13 undescribed forms, including some found near Abidjan by Villiers and Delamare-Deboutteville. After initially recoiling from the maze, Bernard decided to try to institute a little order, albeit provisional, and prepared a key to species known from French Africa. A full revision, he felt, required a knowledge of the three castes of Ponera of the whole Old World. The evidence of Bernard's "Tableau des ouvrières de Ponera pour l'Afrique occidentale" (Key to the workers of Ponera for West Africa") suggests that he used information from the catalogue section of Wheeler's opus (where several Ponera species appear), as Bernard separated 26 species, with 9 being new forms from Nimba. What is not immediately clear, however, is whether all the species covered by the key actually were known from West Africa, i.e. which Bernard had physically seen or which were recorded in the literature. However, he specifically stressed that the forms common to southern Africa and Somalia were omitted, as very few of the "Fourmis microphthalmes" (small-eyed ants) were common to those regions and to the west. The absence of drawings proved a problem for many of the previously described species but, fortunately, he found most of the African forms in the collections of André, Forel and Santschi. Almost at the end of his treatise (p 266-7), Bernard provides a summary of the novel species and findings. Here he again noted "Ponera le tableau des 26 espèces d'Afrique occidentale est donné" - so, I assume that, even though he did not provide actual records for all, he knew evidence for all 26 from one or more West African localities. |
For the present, I have decided to treat Bernard's key as a reliable indicator of the species known from West Africa. Because other findings, some newer, have come to light, I have not tried to make a direct translation nor to prepare a modified version of the key. However, the basic separation of species seems worth repeating and this I have translated († = species listed from Mt. Nimba), providing links to the species. The characters upon which Bernard based his key are: The general colouration and the state of the eyes (0-6 facets) he felt too variable, especially local races. The proportions of the antennal funiculus segments appeared uniform and, thus, were not used. P. rothkirchi Wassmann and P. brevis Santschi were omitted, as he had been unable to see the type specimens and felt the original descriptions were inadequate. In contrast, P. aethiopica was included despite his misgivings. Queens of two species abundant at Nimba had not been described and males required a future revision. |
I have adopted the veracity of the placement of most of the species in Hypoponera found in Bolton's (1995) catalogue. Taylor listed new placements in Hypoponera he made as follows (original status in brackets) - H. abeillei (Ponera); H. angustata (Cryptopone); H. boerorum (Ponera coarctata ssp); H. cammerunensis (Ponera abeillei var, misspelt with one m); H. imatongica (Ponera coarctata ssp); H. natalensis (Ponera coarctata ssp); H. punctatissima (Ponera). |
Genus Hypoponera - hypoponera-group. As
defined by Santschi (1938a) - with alitrunk profile flat and unbroken
line, with no suture on dorsum at usual position of metanotal suture - |
Genus Hypoponera - similoponera-group. Apparently all those species formerly classified under Ponera, i.e. with a distinct metanotal suture but lacking a subpetiolar process with a translucent spot (as defined by Taylor, 1969a). There seem to be about as many members known from sub-Saharan Africa as from Asia and Australasia or the Neotropics. Those from sub-Saharan Africa can be divided into two species-complexes as follows - similoponera-complex, species with a thick petiole
scale which is triangular or at least less than square when seen from
above - squamoponera-complex, species with a thin, squamiform,
petiole, dorsally twice as wide as long, in profile high and flat - This has altered slightly with the study by Seifert (2003b) of
specimens previously identified as Hypoponera punctatissima,
the sub-Saharan species probably is Hypoponera schauinslandi,
see revised key below for separation. Unfortunately, Seifert's
numerical analysis method is clearly beyond the capacity and probably
too time-consuming for easy, every day use. [Note: Bolton & Fisher (2011: From the small number of photographed queens, see below,
plus the few adequate descriptions, it seems that these may be
separable from the true Hypoponera
in having flat, ovoid (often angled) eyes, set some distance back from
the posterior margin of the clypeus; frontal notch reaching the
anterior ocellus. The true Hypoponera
have circular,
convex (protruding) eyes, set close to the posterior margin of the
clypeus; the frontal notch is short and weakly incised. |
Sexuals. Very few have been described, * = photographs |
The comprehensive revisionary study by Bolton & Fisher
(2011)
appears at first sight to bring clarity to the confused
situation. When looked at in depth, however, it confuses to
situation, as much by its omissions as by its contents. For a modern paper it is remiss in providing no illustrations
for eight species, of which six were defined as new species. Moreover
many of the separating characters, such as sculpturation on the
posterior face of the petiole, are not visible in the apparently
excellent automontage photographs (nor on the source images locatable
at Antweb.com). |
Key to workers - developed from that in Bolton & Fisher (2011) |
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PONERINAE Introduction |
© 2007, 2008, 2009, 2010, 2011, 2012, 2017 - Brian Taylor
CBiol
FRSB
FRES 11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K. |
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