The Ants of Africa
SUBFAMILY MYRMICINAE - Genus Pyramica - subgenus Serrastruma
Genus Pyramica

Subgenus Serrastruma Brown (1948: 107)

Diagnostic Features - Mandibles elongate, triangular, and serially denticulate, with more than 20 denticulae, the basal 4-8 possibly much bigger than the others. Antennae 6-segmented, second and third funicular segments reduced. Antennal scrobes present. Promesonotal suture may be present as a weak impression. Pronotum may be differently sculptured to the mesonotum. Metanotal groove impressed, propodeum armed with a pair of teeth, which may be reduced. Spongiform appendage of pedicel usually reduced. All species golden yellow.

An early key to African and Madagascar dacetines is that of Santschi (1913b); that, with modern annotation, is {original description}.

Genus first separated by Brown (1948e), as a subgenus of Smithistruma, and raised to full genus by Brown (1949d). Subsequently Brown (1952e) reviewed many of the then known specimens, but Bolton (1983) completely revised the genus with a number of synonymies and several new species being defined. Bolton (1999) has made a radical revision and now has Serrastruma as a junior synonym of Pyramica Roger.

For convenience, I have retained Serrastruma as a subgenus of Pyramica and, so, have kept the key.

All members of the subgenus are from sub-Saharan Africa, with ludovici and simoni having spread to Madagascar and Mauritius.

Bolton (2000: 269 ff) had the following species-group (wholly matching the subgenus, so why Bolton felt a species-group name should be erected is curious): lujae-group: bequaerti, concolor, depilosa (sp.n.), dotaja, geoterra, inquilina, lucifuga (sp.n.), ludovici, lujae, maynei, miccata, serrula, simoni and sulumana.  I add braeti and mckeyi.


Key to workers of African species (adapted from Bolton, 1983; and Bolton, 2000: 272; couplets 1 -> 9 -> 10 ff to 22):

Pyramica inquilinaKnown only from inquiline queens Zare (Ruwenzori) - inquilina
1 {short description of image}With the head in full-face view the upper scrobe margin just behind the level of the eye without a projecting long hair (Bolton 2000 couplet 11)
2
-- {short description of image}With the head in full-face view the upper scrobe margin just behind the level of the eye with a projecting long flagellate or simple fine hair (Bolton 2000 couplet 17) 9
2 Dorsum of head and alitrunk with very conspicuous thickly spatulate to scale-like coarse ground-pilosity 3
-- Dorsum of head and alitrunk with inconspicuous slender, very narrowly spatulate ground-pilosity 6
. Dorsum of head and alitrunk with very conspicuous dense, thickly spatulate to scale-like coarse ground-pilosity; antennal scapes relatively short SI 73-83 .
3 Dorsal alitrunk sculptured; sides of head not broadly convex posteriorly; TL 2.3-3.0 mm; dull brownish-yellow to mid-brown 4
-- Dorsal alitrunk glassy smooth; sides of head broadly convex posteriorly; TL 2.6-2.7 mm; glossy brown 5
4 {short description of image}Occiput in profile with 2-3 pairs of stout erect hairs; pronotal dorsum densely and sharply costulate (striate?); ground pilosity of numerous curved, broadly spatulate and conspicuous hairs; upper margin of scrobe well defined; TL 2.3-3.0 mm, HL 0.52-0.66, HW 0.44-0.54, SL 0.34-0.42, PW 0.31-0.41; dull brownish-yellow to mid-brown .
. {Pyramica maynei} Pan-African - maynei
--
Pyramica depilosaOcciput in profile with a single pair of stout erect hairs; pronotal dorsum sparsely and weakly costulate (striate?); ground pilosity of sparse inconspicuous, narrowly spatulate hairs;upper margin of scrobe weak and incomplete; TL 2.4-2.6 mm, HL 0.57-0.60, HW 0.46-0.48, SL 0.41-0,43, PW 0.36-0.38 Cameroun & Gabon - depilosa
5 Pyramica lucifugaMesonotum dorsum without raised and prominent anterolateral angles; mesonotum and dorsum of propodeum finely reticulate-punctata not as smooth and shiny as pronotum; head narrower and scape longer, CI 74-75, SI 86-89; TL 2.0 mm, HL 0.48-0.50, HW 0.36-0.37, SL 0.32, PW 0.27-0.28 Cameroun & Kenya - lucifuga
-- {short description of image}Mesonotum dorsum with raised and prominent anterolateral angles; mesonotum and dorsum of propodeum as smooth and shiny as pronotum; head broader and scape shorter, CI 90, SI 73-74; TL 2.6-2.7 mm, HL 0.58-0.60, HW 0.52-0.54, SL 0.38-0.40, PW 0.34-0.37; glossy brown .
. {short description of image} Cameroun & Kenya - geoterra
. Dorsum of head and alitrunk with inconspicuous slender, very narrowly spatulate ground-pilosity .
6 Pronotal humeri each with a long, fine flagellate hair 7
-- Pronotal humeri without a long, fine flagellate hair 8
7 Pyramica sulumanaLeading edges of scapes with fine simple outcurved short hairs; mandibles longer, basal 4-5 denticles not much enlarged; metanotal groove not impressed; TL 2.0 mm; pale yellow Cameroun - sulumana
-- {Pyramica bequaerti}Mandibles and scapes relatively short; occiput with a transverse row of 2 or 4 erect hairs on the posterior margin and an anterior pair of hairs
Cameroun & Zaire - bequaerti
-- {Pyramica mckeyi}Dorsal alitrunk weakly sculptured; sides of head broadly convex posteriorly; TL 1.96 mm, HL 0.45, HW 0.36, CI 90, SL 0.26, SI 68, PW
0.25; orange yellow
Cameroun - new species - mckeyi
-- {short description of image}Leading edges of scapes with fine simple outcurved short hairs; mandibles longer, basal 4-5 denticles not much enlarged; metanotal groove not impressed; TL 1.5 mm; pale yellow (postdates Bolton 2000)
Cameroun - Pyramica nsp CASENT0414575
. Pronotal humeri without a long, fine flagellate hair .
8 {short description of image}Pronotal humeri each with a short, stout clavate hair; leading edges of scapes with projecting short clavate hairs; mandibles shorter, basal 4-5 denticles conspicuously enlarged; metanotal groove not impressed; TL 1.9-2.3 mm; dull yellow to yellowish-brown .
. {short description of image} Ghana - miccata
-- {Pyramica braeti} TL 1.8 mm; HW 0.38, HL 0.48, CI 87, SL 0.26, SI 65, PW 0.27 dull brown
Congo - new species - braeti
return to key With the head in full-face view the upper scrobe margin just behind the level of the eye with a projecting long flagellate or simple fine hair .
9 Main sculpture of dorsal pronotum dense reticulate-punctation, with or without overlaying but secondary costulate or striate sculpture 10
-- {Pyramica simoni }Main sculpture of dorsal pronotum of longitudinal to oblique striae or costulae, or smooth and unsculptured; secondary punctate sculpture usually absent or no more than feeble 13
10 {Pyramica ludovici}In full-face view, the mandibles with enlarged basal denticles, usually distinctly so; TL 1.9-3.0 mm; yellow to mid-brown .
. {Pyramica ludovici} Pan-African - ludovici (part)
-- Basal series of mandibular denticles not markedly enlarged 11
11 {short description of image}Mesonotum with 3-4 pairs of short, erect slender hairs, posterior pair close to metanotal groove; ground pilosity of promesonotum strong and conspicuous in profile; punctate sculpture of head and alitrunk strong and sharply defined; TL 1.9-2.3 mm; dull yellow to yellowish-brown .
. {Pyramica serrula} Pan-African - serrula
-- Mesonotum usually with a single anterior pair of apically thickened to strongly clavate hairs; rarely a second pair present, if so close to first pair; ground pilosity of promesonotum feeble and inconspicuous; punctate sculpture on head and alitrunk usually fine 12
12 {short description of image}Dorsum of head behind highest point of vertex with 4 relatively slender simple hairs, plus a further pair forward of vertex high-point; in full-face view the upper scrobe margins are not indented at the site of the projecting hair; postpetiole with more than one pair of hairs; TL 2.2-3.3 mm; yellow to medium brown .
. Pyramica lujae Pan-African - lujae
-- {short description of image}Only 2-4 hairs behind highest point of vertex of head dorsum; these hairs thickened apically to clavate; in full-face view upper scrobe margins usually conspicuously indented at site of projecting hair; postpetiole with only a single pair of standing hairs; TL 2.0-2.2 mm; yellow to yellowish-brown .
. {Pyramica (Serrastruma) concolor} Pan-African - concolor
return to key Main sculpture of dorsal pronotum of longitudinal to oblique striae or costulae, or smooth and unsculptured; secondary punctate sculpture usually absent or no more than feeble .
13 {short description of image}A pair of very long flagellate hairs on the pronotal humeri and pronotum; first gastral tergite with only a single pair of long simple hairs; TL 2.3-2.5 mm; blackish-brown to jet black
. {Pyramica dotaja} Cameroun & Gabon - dotaja
-- Pronotal humeri but not mesonotum with flagellate hairs; mesonotum usually with a single pair (rarely 2 pairs) of stout hairs, thickened or clavate apically; first gastral tergite with thickened or clavate hairs 14
14 {Pyramica ludovici}In full-face view, the mandibles with enlarged basal denticles, usually distinctly so; TL 1.9-3.0 mm; yellow to mid-brown .
. {Pyramica ludovici} Pan-African - ludovici (part)
-- {Pyramica simoni}Mandible without enlarged denticles; in profile postpetiole with ventral spongiform lobe greater in area than the exposed area of postpetiole; TL 2.4-3.0 mm; golden yellow .
. {Pyramica simoni} Pan-African - simoni
Contents MYRMICINAE Introduction
2007, 2008, 2009, 2010, 2011, 2013, 2015 - Brian Taylor CBiol FSB FRES
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