The Ants of Africa
SUBFAMILY PONERINAE - Genus Platythyrea
Contents - Ponerinae - PONERINAE Introduction

Genus Platythyrea Roger (1863a: 172)

In Tribe PLATYTHYREINI.

Diagnostic Features - The entirety of the head, alitrunk, pedicel, gaster and appendages with very fine shagreening and with scattered larger, shallow punctures. All surfaces covered by an extremely fine dense pubescence and devoid of standing hairs. Two pectinate spurs on the end of the middle and hind tibiae, and a median tooth on the pretarsal claws. Alitrunk with promesonotal suture distinct, but the metanotal suture obsolete or absent.

Roger's (1863a) genus definition is at {original description}.

Revised by Brown (1975), from where the following key is derived. Brown noted that crucheti appeared to be possibly no more than a small form of conradti.

Key to workers known from Africa

Male & queen only known Zimbabwe - matopoensis

not in Brown's key; original description, notably frontal carinae being close together (almost contiguous) and petiole shape suggests, similarity to arnoldi Tanzania - viehmeyeri
1 {Platythyrea occidentalis alitrunk}Opening of propodeal spiracle round or oval 2
-- {Platythyrea gracillima alitrunk}Opening of propodeal spiracle elongate, slit-shaped 8
2 Large, AL > 3.8 mm 3
-- Smaller, AL < 3.8 mm 4
3 {Platythyrea cribrinodis}Petiole with rounded node; TL 14-16.5 mm; dull black East Africa - cribrinodis
-- {Platythyrea frontalis}Dorsal surfaces with no more than fine sculpturation, in parts shiny; coarse puncturation small and shallow; petiole with distinctive flat-topped node; TL 8.4 mm; black with reddish appendages West Africa - frontalis
4 {Platythyrea cooperi}Posterior margin of petiole node unarmed; mandibles edentate; TL 6.5 mm; brownish-blackmost of head and appendages more red South Africa - cooperi
-- Posterior margin of petiole node with 2-3 blunt teeth; mandibles distinctly toothed 5
5 Platythyrea tenuisTL 5.5 mm plus; HW 1.1-1.25 mm in full face view (Brown key wrong on this); eye length about 0.22 HW, scapes just reach  the occipital margin of head; black with lower legs ferruginous Cameroun - tenuis
-- HW > 1.0 mm in full face view, scapes at least slightly exceeding posterior margin of head 6
6 {Platythyrea occidentalis}TL 7-9 mm; funiculus segment 2 about twice as long as segment 3 and much longer than the eye; eye small; posterior margin of petiole with sharp, angular teeth; black appendages brownish red
Note: the worker described by Arnold (1954) differs and may be a separate species
West Africa & Congo Basin - occidentalis
.
Uganda specimenTL ca 7.6 mm (Arnold 7.0 mm) HW 1.35 HL 1.6 SL 1.1 PW 09.5 EL 0.2.  Head relatively shorter and with weakly convex sides; petiole also with more convex sides in dorsal view but flat-tooped rather than shallowly domed.  With more specimens it seems likely that Arnold described the worker of a distinct species separate from occidentalis. Notable is the lack of the puncturation that is present on the whole of the Liberia worker (above). Uganda specimen
-- Funiculus segment 2 about same length as that of 3 and much shorter than the eye 7
7 {Platythyrea modesta}Posterodorsal margin of petiole with a sharp margin that includes the two lateral teeth; TL 6.6-7.0 mm; generally black with grey pubescence, appendages red-brown .
. {Platythyrea modesta} Panafrican forests - modesta
-- {Platythyrea schultzei petiole}Posterodorsal margin of petiole more or less rounded between lateral teeth and base of mandible with a conspicuous dorsolateral grove; sculpture opaque with numerous conspicuous punctures on the petiole and other dorsal surfaces; TL 8.5-9.5 mm; black front of head and appendages red .
. {Platythyrea schultzei} Southern Africa - schultzei
. Opening of propodeal spiracle elongate, slit-shaped .
8 {Platythyrea gracillima}Eyes small, no wider than scape; petiole node with sharp projecting posterodorsal margin; TL 9.0-10.7 mm; overall black, appendages and first gastral segment red; remainder of gaster yellow .
. {Platythyrea gracillima} West Africa & Congo Basin - gracillima
-- Eyes much longer than width of scape; petiole with posterodorsal margin no more than weakly projecting 9
9 {Platythyrea arnoldi petiole}Posterior face of petiole node concave, sharply distinct from dorsum, with weakly overhanging border; mesonotum not impressed; TL 11.8-13.5 mm; black, mandibles castaneous red .
. {Platythyrea arnoldi} Zimbabwe & Zare - arnoldi
-- Posterior face of petiole flat to convex, continuing from rounded dorsum; mesonotum often impressed 10
10 {Platythyrea lamellosa}Petiole node long and narrow; mesonotum distinctly impressed over whole length; TL 12.5 mm; black but dull and pruinose, appendages more brown, mandibles and tarsi red .
. {Platythyrea lamellosa} southern Africa - lamellosa
-- Petiole node not so long and narrow; mesonotum not hardly impressed 11
11 {Platythyrea conradti}Larger, AL > 3.8 mm; TL ca 12.5 mm; generally black but with dull grey appearance due to dense pubescence, extremities red-brown .
. {Platythyrea conradti} West Africa - conradti
-- Platythrea cruchetiSmaller AL < 3.8 mm; TL 7.5 mm; pruinose black Angola - crucheti
Contents PONERINAE Introduction
2007, 2008, 2013, 2014, 2015 - Brian Taylor CBiol FSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.

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