Genus Lepisiota (Mayr)
(previously Acantholepis
Mayr, 1861: 42)
Genus
Introduction in Ants of Africa
In Tribe PLAGIOLEPIDINI.
Diagnostic Features - Antennae 11-segmented. Eyes well
developed, ocelli present but may be reduced. Mandibles with the apical
margin oblique and dentate, overhung by clypeus. Alitrunk constricted
in the mesonotal region, the propodeum swollen and bidentate or
bituberculate. Petiole a scale with the dorsal margin bispinose,
bidentate or emarginate. Acidopore borne on a conical projection of the
hypopygium, surrounded by a fringe of hairs.
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The evidence at present for this area is for the existence of two
species-groups - note the early authors mostly used two "species" -"capensis" and
"frauenfeldi". The capensis species had a petiole which
was bidentate not bispinose. True Lepisiota capensis (from South Africa)
is black with sparse erect black hairs. Some of the confusion may stem
from Forel (1892a: 43) where his key had - capensis (from South
Africa, Madagascar and Indian continent) with "erect pilosity whitish,
abundant on body, none on tibiae and scapes". also "petiole scale
narrow with two short spines" - This clearly was erroneous in both
those aspects.
Note - the diagnosis and separation of the carbonaria-group
species is somewhat speculative, as the many of original descriptions
are minimal separations of "subspecies". The efforts of Collingwood,
later with Agosti, are admirable but the papers again give fairly
minimal information and their separations also seem to owe more than a
little to informed guesswork. Some species are included for comparison
with those now known from Egypt, e.g L. simplex and L. incisa.
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frauenfeldi-group
- elongated, shiny species; with long antennae and legs; propodeum and
petiole usually with sharp prominences or spines; plus reduced or no
pilosity and little pubescence.
The type form Lepisiota frauenfeldi is not known from Egypt, an analysis can be seen on "frauenfeldi"
- see analysis page
Egyptian species are shown below.
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carbonaria-group
- stockier
species, duller in appearance due to dense sculpturation; mostly TL
2.0-2.5 mm; propodeum with rounded or blunt prominences and petiole
without spines; shorter antennae and legs; plus substantial coarse
pilosity and dense variably coarse pubescence |
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canescens-group - shiny with fine erect pilosity. As yet none reported from Egypt.
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Lepisiota frauenfeldi species-group
1 |
Slender elongated species with very long
antennae, SI at least 175, and legs |
2 |
-- |
Stocky and less elongated with shorter
antennae,
SI ca 150, and legs |
4 |
2 |
SI ca 230; almost
completely black, except for scapes,
mandibles and lower legs |
gracilicornis |
-- |
SI < 200 |
3 |
3 |
TL 2.3-3.0 mm; with
relatively long, narrow head (cf frauenfeldi)
upper marging of petiole weakly incised (less than frauenfeldi);
SI ca 175 |
nigrescens |
4 |
TL 2.0-3.2 mm;
petiole scale wide & acutely dentate;
propodeum with short teeth about than 0.5 X basal space; clypeus with
weaker median carina; less shiny but finely and distinctly reticulate;
alitrunk black with no more than mesonotum red; SI ca 150 (photographed
specimens & Finzi drawing) |
syriaca |
-- |
Black specimens from
desert areas with workers TL 2.8-3.0
mm, possibly alternatively identifable as bipartita, which
remains as a subspecies of frauenfeldi (see above). In his key,
Finzi (1936: 188) noted - petiole scale large (bipartita type);
maximum width at about about double the depth of the incision of the
scale. Agosti & Collingwood (1987b: 279, in key) separated nigra
from frauenfeldi as the former being wholly black with a smooth
pronotum; whereas the latter has "part of body usually with a small
patch of red, pronotum sculptured". |
Questionable record from
Egypt
- nigra |
Lepisiota carbonaria
species-group
Collingwood's (1985) separation of the carbonaria-group,
with some points and measurements from Collingwood & Agosti (1996),
and additional material on African species gives the following (the
links are to individual species pages) -
Species with the head and gaster sculptured
1 |
HW 0.61-0.62 SI 116-118
Propodeum profile flat with junction of dorsum and declivity an acute
angle but without teeth or spines; erect hairs sparser and shorter,
gaster with spare pubescence; overall
appearance duller; eyes flatter and appear dull; perhaps slightly
redder in colour with more distinctively contrasting mandibles,
seemingly always visible
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obtusa
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-- |
Petiole rounded with very
shallow emargination; propodeum with blunt projections only; whole body
sculptured and dull; alitrunk entirely without dorsal hairs; HW
0.57-0.58 SI 107
Base colour dark red-brown; head in full face view heart shaped, erect
hairs short and not obviously distinctive; overall appearance only
weakly shiny, due to a visibly shagreened (roughened) surface
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erythraea |
-- |
Petiole spines about half as long as their intervening
width; HW 0.60-0.61 SI 116
Specimen from Sudan
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carbonaria |
-- |
Petiole spines about half as
long as their intervening width or less, scale narrow apically in
profile; with abundant variably long erect white hairs on all surfaces;
distinctive downcurved hairs on clypeus.
With somewhat longer erect hairs on the pronotum,
general
pilosity
is shaggier, with abundant pubescence on the gaster; head in full face
view with a more rectangular appearance; the mandibles often concealed
when closed; eyes distinctly convex and protruding; overall appearance
shinier and blacker, eyes viewed from most angles seem to be black
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hirsuta |
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Petiole dentate; coarse dorsal
sculpture especially on pronotum not obscuring cuticular shine; one or
two occasional pronotal hairs; HW 0.62 SI 112-113; Emery (1897e) erect
hairs on gaster confined to apical row on each tergite; pubescence more
copious than other carbonaria; almost all of body sub-opaque,
metanotum and propodeum opaque
Specimen from Sudan
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depilis |
--
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Petiole dentate; sculpture fine but visible; TL 3.2-4
mm; shiny; Tunisia
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pubescens |
Species with the head and gaster smooth and brilliant
1 |
Covered with fine, sharp,
whitish hairs; TL max 2.5 mm; petiole spines weak (?) less
developed than type (capensis) but clear; ? petiole with
prolonged posterior pedicel. BT - head ovoid narrower anteriorly,
scapes darkened apically otherwise with funiculi brownish yellow; specimen from Sudan for comparison; widely
distributed across the Sahel
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canescens |
-- |
very few erect hairs on alitrunk;
for comparison; type location Somalia
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simplex |
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