Contents Contents The Ants of Egypt
SUBFAMILY FORMICINAE - Genus Lepisiota (Mayr)

Genus Lepisiota (Mayr) (previously Acantholepis Mayr, 1861: 42)

Genus Introduction in Ants of Africa


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.

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.

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.
{Lepisiota gracilicornis}
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 {Lepisiota carbonaria}
canescens-group - shiny with fine erect pilosity. As yet none reported from Egypt.
{Lepisiota canescens}

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 {short description of image}SI ca 230; almost completely black, except for scapes, mandibles and lower legs gracilicornis
-- SI < 200 3
3 Lepisiota aegyptiacaTL 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 {short description of image}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
-- Lepisiota nigraBlack 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 {Lepisiota obtusa}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
-- {Lepisiota erythraea}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
-- Lepisiota carbonariaPetiole spines about half as long as their intervening width; HW 0.60-0.61 SI 116
Specimen from Sudan
-- {Lepisiota hirsuta}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
{Lepisiota depilis}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
Lepisiota pubescensPetiole dentate; sculpture fine but visible; TL 3.2-4 mm; shiny; Tunisia

Species with the head and gaster smooth and brilliant

1 {Lepisiota canescens}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
-- Lepisiota simplexvery few erect hairs on alitrunk; for comparison; type location Somalia
2005, 2006, 2010, 2013, 2014, 2015, 2019 - Brian Taylor CBiol FRSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.