Plectroctena minor Emery

Type location Ivory Coast (Plectroctena minor n. sp., Emery, 1892d: 556, illustrated, queen - see below; Emery, 1902c: 32, worker; Wheeler, 1922: 88, male) Assinie
junior synonyms
insularis (Plectroctena minor Em. v. insularis n. var., Santschi, 1924a: 169, illustrated, worker) from Fernando Po I., Conrad - see http://www.antweb.org/specimenImages.do?name=casent0915288&project=allantwebants where labelled "fernandensis"
liberiana (Plectroctena minor Em. v. liberiana n. var., Santschi, 1924a: 169, illustrated, worker) from Liberia - see http://www.antweb.org/specimenImages.do?code=casent0915291
perusta (Plectroctena minor Em. v. perusta n. var., Santschi, 1924a: 168, illustrated, worker) from Cameroun, Barumbistation, Preuss - see http://www.antweb.org/specimenImages.do?code=casent0104650
all forms described (see Bolton, 1995) .

Emery's (1892d) illustrated description of the queen is at Emery's (1902c) description of the worker is at Santschi's (1924a) description of the species s.s. is at and those of perusta, liberiana and insularis are at . Bolton's modern description (1974b: 324, mandible and petiole profile) is at .

Plectroctena gabonensis Santschi -  Type location Gabon (Plectroctena gabonensis n. sp., Santschi, 1919a: 336, worker; Bolton, 1974b: 323, queen) Libreville, Chalot - see http://www.antweb.org/specimenImages.do?code=casent0915472

Worker and queen described (Bolton, 1974b, not illustrated) . Note - Bolton & Brown (2002: 11) revised this to a junior synonym of minor.

Santschi's (1919a) description is at . Bolton's modern description (1974b) is at

WORKER - TL 12.8-14.0 mm; similar to minor but slightly smaller; first gastral tergite with transverse groove very weak, usually only visible in middle of sclerite; eye smaller. Colour deep red-brown (minor is black).

Original collection from Libreville, Gabon, by Chalot, 1.xii.1897.

Bolton (1974b) lists records from Gabon, Equatorial Guinea (Fernando Po I.) and Zaïre - 6 findings. Now known from Cameroun, collected by the Campo Forest study (Bolton, Dejean & Ngnegueu, 1992), four samples, two from soil, one from rotting wood and one from an abandoned termitarium of Cubitermes banksi.

The photomontage of the type queen is collated from http://www.antweb.org/specimen.do?name=casent0903929.

The photomontage of the type worker of liberiana is collated from http://www.antweb.org/specimen.do?name=casent0915291.

Nigeria specimen (Taylor, 1976: 29). WORKER. TL 14.38 mm, HL 3.23, HW 3.17, SL 2.15, PW 1.90
Colour dark red-brown, shiny. All over sculpturation of scattered small hair-pits, very faint striations on the lateral alitrunk and petiole.
Collected from a rotten log by Bolton at the Cocoa Research Institute of Nigeria, Idi Ayunre. He noted that fragments of millipedes were among the detritus of an excavated nest. Others TL 15.2-17.6, and otherwise generally larger, and darker (Bolton, 1974b).

Original collection from Assinie, Ivory Coast, by Ch. Alluaud, vii-viii 1886. The collection of perusta was at Barumbistation, Cameroun, by Preuss.

Wheeler (1922) listed it also from Sierra Leone (no details), Ghana (Aburi, F. Silvestri), Cameroun (Victoria, F. Silvestri), plus Fernando Po and Zaïre.

Bolton (1974b) also found it in Ghana, at CRIG, and it was described as not uncommon in eastern Ghana (Belshaw & Bolton, 1994b), although not found by them.

After examining further material from - Ghana, at Tafo, Wiawso and Odomi River, by D. Leston; Togo, at Palimé, Klouto, by Vir; Cameroun, at Ottotomo, Ndupe and Nzi, by A. Dejean, and Nkoemvon, by D. Jackson; Gabon, La Fôret des Abeilles, by S. Lewis; and Zaïre, Kinzambi, by A. Dejean; Bolton & Brown (2002) concluded the variations previously used to separate minor and gabonensis were insufficiently consistent to justify the separation into two species. They placed gabonensis as a junior synonym of minor.

Working with colonies established from field populations in the Kala, Matomb (Pan Pan), Ndupé and Ottotomo forests of southern Cameroun, Suzzoni, Schatz & Dejean (2000) used a cafeteria method of investigating the preferred prey of this species and conclusively demonstrated the "essential" nature of millipedes, with other arthropods being ancillary. Without millipedes in the diet of larvae in large colonies of P. minor winged females were not produced and the production of workers was reduced. The absence of millipedes, however, did not appear to affect the production of males. Foundling queens, avoiding tackling large prey and the illustration (right) from their paper shows such a queen with a woodlouse. They described how normal foraging is under the bark and in the wood of the rotting logs, which also are used as the nest sites.

Oxford University Museum specimens

Plectroctena minor B Taylor det.	Uganda A Omer	2006	Hnad collected	1
Plectroctena minor B Taylor det.	Central African Republic P Annoyer	06.vi.1998 Dzanga-Sangha 02°53’ N 16°15’ E	Bayanga-Lidjomba	2

The photomontage is of a worker from Uganda, collector Awatif Omer, 2006.

The photomontage is of a worker from the Central African Republic, Dzanga-Sangha NP; Bayanga-Lidjombo; 07.vi.1998; 10.30-12.30 h, collector Philippe Annoyer. 

The photomontage is collated from http://www.antweb.org/specimen.do?name=casent0003067. The specimen is from Gabon, Woleu-Ntem; 31.3 km 108° ESE Minvoul; 02°04'48"N 012°24'24"E; 600m; B L Fisher, BLF1673; rotten log in rain forest; 10.ii.1998.