Genus Lepisiota Santschi 1926a: 15 (previously Acantholepis Mayr, 1861: 42)

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.

Mayr's (1861: 42) genus description for Acantholepis, is at . Arnold (1920: 544) gave an expanded translation of Acantholepis, is at .There are no modern revisions.

On the generic nomenclature, Bolton (1994: 51) gave Acantholepis as reduced to the status of a homonym of Lepisiota but cited no authority. Acantholepis was used by all early authors and even as late as Belshaw & Bolton (1994b). Hölldobler & Wilson (1990) gave the authorities as being Acantholepis Mayr 1861: 42 and Lepisiota Santschi 1926a: 15 (as a subgenus of Acantholepis). The name Lepisiota had been applied to Acantholepis species in Baroni Urbani, Bolton & Ward (1992: 303) but without any explanation. Bolton (1995: 33) revealed the older name was applied to a fish genus from Denmark by Kroyer in 1846. Thus he raised, Lepisiota, formerly a subgenus of Acantholepis, to genus status for the ants. The need for a replacement name had been recognised by Pagliano & Scaramozzino (1990: 4), but Bolton (1995: 22) had their Baroniurbania as an unnecessary replacement name, preceded by the earlier Lepisiota.

It seems that the prior formal synonymy of Baroniurbania under Lepisiota was by Xu. 1994. A taxonomic study of the ant genus Lepisiota Santschi from Southwestern China (Hymenoptera Formicidae Formicinae) Journal of Southwest Forestry College, 14(4): 232-237; in Chinese but that was published too late for inclusion in Bolton (1995).

Reference: Pagliano, G. & Scaramozzino, P. 1990. Elenco dei generi di Hymenoptera del mundo. Memorie della Societa Entomologica Italiana, 68, 1-210]

"Baroniurbania nom. nov. per Acantholepis Mayr, 1861 (44 Formicinae) preocc. da Kroeyer, 1846.
Derivation nominis: dedicato al mirmecologo Ceare Baroni Urbani." Reference: Kröyer, H. 1846. Danmarks Fiske, 3, 1-704 (p 98), København.

There is an anomaly here as Mayr (1861) defined his new genus Acantholepis with a single species, A. frauenfeldi, the species he first described as Hypoclinea Frauenfeldi (Mayr, 1855: 378). In his key to genera (Mayr 1861: 26) he separated Acantholepis n. g. and Plagiolepis n. g. by the former having ocelli and the latter not; also by the Acantholepis having a small, slender alitrunk, the propodeum with small spines; whereas, Plagiolepis had the pronotum and propodeum wider than the mesonotum, and the propodeum unarmed. A. frauenfeldi was listed as the type species by Emery (1925b: 23). Wheeler (1911f: 165) listed Hypoclinea as a subgenus of Dolichoderus, and gave as type species Formica quadripunctata Linnaeus, 1771 (second species by designation [i.e. in the Mayr, 1855, list]), presumably as it was described first. The latter, however, now is regarded as Dolichoderus quadripunctatus (Linnaeus).

Other than L. rothneyi, the sole Acantholepis species reported or described by Santschi from Asia was Plagiolepis (Anacantholepis) Demangei (Santschi, 1920a); a third species Plagiolepis moelleri Bingham (1903) was listed under Asian Plagiolepis (Anacantholepis) by Emery (1925b: 23).

As a genus type L. rothneyi is anomalous; with a low rounded petiole and the propodeum profile smoothly rounded without sign of spines or even angular protuberances. With the exception of its two Asian relatives, all other species presently included in Lepisiota have a raised petiole scale and at least a pronounced angle between the propodeum dorsum and declivity; commonly teeth or spines are present on the propodeum, the petiole, or both.  Ocelli are inconsistent in their development, ranging from easily seen to apparently absent. As with its two relatives, rothneyi has short antennal scapes that surpass the occiput by no more than one-sixth their length. With few exceptions, e.g. L. mota from Angola, that otherwise have the "Acantholepis" characters, the other species have scapes that surpass the occiput but at least one-quarter of their length.

Emery (1925b: 23) had it in Plagiolepis. Forel's (1894c) description is at . Bingham (1903: 320) had it in his key to Indian Plagiolepis and a description; these are . The confused status of the "Plagiolepis" species is shown by the first couplet of the key separating off the now Anoplolepis gracilipes (listed as Plagiolepis longipes); Plagiolepis moelleri remains in that genus but Plagiolepis wroughtoni (originally described as Plagiolepis Rothney race Wroughtoni new stirps, Forel, 1902d: 293) now is under Lepisiota.

It seems possible, perhaps highly likely, that a modern review of the type specimens of Lepisiota rothneyi, the subspecies listed by Bolton (1995: 228) and its two relatives, would lead to their being reverted to quite ordinary Plagiolepis, or a separate genus Lepisiota, with three member species, rothneyi, demangei and moelleri. In the latter context the only obvious difference is the presence of poorly developed ocelli. If L. rothneyi is placed in Plagiolepis or Lepisiota the latter is invalid as the replacement genus name for Acantholepis.

From the original descriptions, illustrations and specimens that I have drawn or illustrated, I have attempted to draw up keys to the species. These are not intended to be truly authorative but at least a guide to the apparent main groups. It is apparent that a modern review of the type specimens and fresh material would lead to synonymization and, especially, in the case of "capensis", separation into several more species. Having decided (2004) to expand the coverage to all species from sub-Saharan Africa, it has become clear that the dimorphism I found in the specimens I tentatively identify as Lepisiota cacozela is not unique, or an aberrant occurrence, as Weber (1943c) described L. megacephala from a single apparent soldier. I have been unable to find any reference to dimorphism from outside Africa, although there is a range of sizes in L. rothneyi from India.

An early key which included Acantholepis species from Africa was compiled by Forel (1892a). This is at and (Indian species) . Forel referred to capensis as having whitish erect pilosity on the body but not on the tibiae or scapes. The colour of the pilosity in the type capensis, i.e. from South Africa, however, is clearly blackish.

Notes on sub-Saharan Africa species

Strickland (1951a) described Acantholepis as small black ants, more likely to be found on seedling cocoa than on mature trees and essentially soil nesting. He regarded them as of little economic importance as far as cocoa was concerned.

Bernard (1952) described genus members (as Acantholepis) as more common than their relatives Plagiolepis and Anoplolepis in the Guinea, Mt. Nimba surveys; adding that the nests often are very resistant to inundation, which leads to their being abundant among the ants known from close to the River Niger (according to Monod). Under one of the species, he added that the Acantholepis are individually very variable, and refrained from describing new species as it would be better to await more examples. Bernard also referred to species in the subgenus Pseudacantholepis Santschi, being very small and poorly collected forms; and, other than A. laevis [see below as a subspecies of capensis], previously unknown from French West Africa. Bolton (1995) noting that he found no record of type species for the subgenus and (apparently) no Santschi reference, regarded the subgenus name as "unavailable".

Lepisiota capensis (Mayr) - listing as in Bolton (1995: 227) with links to species as I have separated them

Type location South Africa (Mayr, 1862: 699, worker; Mayr, 1862: 770, male; also Mayr, 1866: 57, male; Emery, 1877b: 366, queen)
subspecies
acholli (Acantholepis capensis Mayr, acholli subsp. nov., Weber, 1943c: 382, illustrated, worker & queen) from South Sudan
issore (Acantholepis capensis Mayr, issore subsp. nov., Weber, 1943c: 383, illustrated, worker & queen) from South Sudan; variety thoth (Weber, 1943c: 383, illustrated, worker & queen) from South Sudan
anceps (Acantholepis capensis Mayr v. anceps n. var., Forel, 1916: 438, worker) from Zaïre
specularis (Acantholepis laevior Santschi stirps specularis n. st., Santschi, 1935a: 278, worker) from Zaïre
guineensis (Acantholepis capensis Mayr var. guineensis nov. var., Mayr, 1902: 296, worker) from Ghana, Accra, by R. Buchholz
junodi (Acantholepis capensis Mayr r. Junodi n. stirps, Forel, 1916: 438, worker) from South Africa; may be a variety of incisa (Forel)
minuta (Acantholepis simplex For. v. minuta n. var., Forel, 1916: 438, worker) from South Africa
simplicoides (Acantholepis capensis Mayr var. simplicoides n. var., Forel, 1907g: 86, footnote, worker) from South Africa
laevis (Acantholepis laevis n. sp., Santschi, 1913c: 312, illustrated, worker) from Senegal, St. Louis by Claveau,
lunaris (Acantholepis lunaris n. sp., Emery, 1893f: 250, illustrated, worker) from Sri Lanka
simplex (Acantholepis simplex Forel, 1892a: 43, in key, worker; Forel, 1892e: 350, queen & male) from Somalia
validiuscula (Acantholepis capensis Mayr var. validiuscula n. var., Emery, 1897e: 602, worker) from Somalia
subopaciceps (Acantholepis capensis Mayr v. subopaciceps n. v., Santschi, 1937d: 235, worker) from Angola
(see Bolton, 1995).

"L. capensis"
I have attempted to disentangle the mess with the linked Analysis.
This has led to separation of the following -
capensis (Mayr);
validiuscula (Emery);
guineensis (Mayr) new status;
issore (Weber) new status, with thoth as a variety;
laevis (Santschi) revived status, possibly separate species specularis (Santschi);
lunaris (Emery) revived status (not African);
minuta (Forel) new status;
simplex (Forel) revived status with possibly separate species simplicoides (Forel) and subopaciceps (Santschi)
acholli (Weber) probably a junior synonym of affinis;
anceps (Forel) may be a variety of obtusa (Emery);
junodi (Forel).