The Ants of Africa
Genus Rhoptromyrmex
Rhoptromyrmex opacus Emery

Rhoptromyrmex opacus Emery

return to key {link to the Hymenoptera Name Server} Type location Cameroun (Emery, in Forel, 1909b: 59, footnote, worker) collector L. Conradt - see
junior synonyms
esta (Rhoptromyrmex opacus Emery var. esta n. var., Forel, 1909b: 59, all forms) from Zaïre - see below
laeviceps (Rhoptromyrmex opacus Em. var. laeviceps n. var., Santschi, 1916b: 504, worker) from Zaïre collected at Boma, by Bondroit - see
monodi (Rhoptromyrmex opacus race monodi n.sbsp., Bernard, 1952: 251, illustrated, worker) from Guinea, one worker from Mt. Nimba, Ziéla, station F 32, savannah, collector Lamotte - see
all forms described (see Bolton, 1995) .

{Rhoptromyrmex opacus}Emery's (1909b) description is at {original description}. Forel's (1909b) description of esta is at {original description}. Santschi's (1916b) description of laeviceps is at {original description}. Bernard's (1952) description of monodi is at {original description}, epinotum = propodeum.

Wheeler (1922) described its collection in Zaïre by Bequaert, as nesting in sandy soil in the savannah.

Bernard (1952) described his new subspecies monodi as follows - TL 2.2 mm, length, striation, form of the head and of petiole nodes, similar to the type opacus from Congo. Occiput and thorax brown-black, face red-orange, clypeus yellow (orange in type). Propodeum clearly angular in profle, with two dentiform ridges on the posterior face, angled also on the sides (entirely rounded on the sides in the type).

{Rhoptromyrmex opacus}Bolton's modern description (1986a) is at {original description}.

WORKER - TL 2.5 mm; mandibles large, subopaque with 7-8 teeth, striato-punctate; head large and cordiform, as with transversinodis and globulinodis but shorter and wider, sides very convex; more pronounced forwards, clypeus subcarinate and forming a rounded lobe. Scape reaching posterior sixth of head; funiculus segments 2-8 narrower than long. Metanotal groove distinct (missing on Mayr species). Petiole pedicel short (longer in Mayr species); node rounded cuboid, slightly wider than long; postpetiole node bigger, but no higher. With twelve-segmented antennae; the head and alitrunk usually with dense, opaque reticulate-punctate sculpture; propodeum unarmed; head and gaster always with standing hairs, but not always so on the alitrunk. Colour darkish yellow, head and thorax reddish. (Emery, in Forel, 1909b: 59, footnote, worker; Bolton, 1976, not illustrated; Bolton, 1986, fully illustrated).

Rhoptromyrmex opacus estaForel (1909b) described esta as having a smaller head, somewhat longer than wide, sides less convex and without a medina carina on the clypeus; otherwise similar although shoulders of pronotum more rounded. He also described the queen and male. All the specimens came from the stomach of a Pangolin in Bas Congo, collected by Solon. The latter was referred to by Santschi (1916b) who described laeviceps as differing in having less obvious sculpturation and being shinier.

The photomontage of a cotype of esta is collated from The Smithsonian Institute images at

{Rhoptromyrmex opacus}The photomontage is collated from
Collection details - Congo: ; km. 94 on Kavumu Walikale route; 00°00'00"N 000°00'00"E, 900m. Collection Information: Collection codes: ANTC1254. Date: 17 Sep 1957. Collected by: E. S. Ross & R. E. Leech .


Oxford University Museum specimens

Rhoptromyrmex opacus
B Taylor det.

A Fotso Kuate
Sample 19

03°54'30" N
11°25'58" E
Aphid survey
Rhoptromyrmex opacus
B Taylor det.
E Zassi
03°20'12.0" S
015°28'43.6" E
Village Mah; 24h pitfall trap

{Rhoptromyrmex opacus}The photomontage is of a worker from Congo, Réserve de Lésio-Louna; collector Eric Zassi (pitfall trap 01, t 1)

{Rhoptromyrmex opacus}The photomontage is of a specimen from Cameroun; Babedjou; collector A Fotso Kuate (fk unmounted 19).

© 2007, 2009, 2010, 2011, 2012, 2014, 2018 - Brian Taylor CBiol FRSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.