Wheeler (1922) included the following description of tibialis
WORKER - Length 3.5 mm. Pale castaneous. Propodeum, postpetiole, and
posterior half of gaster of a deeper castaneous tint, passing to
reddish brown. A spot on the vertex and the appendages dark. brown, the
tibiae and metatarsi blackish, the tarsi and the'extremity of the
thorax reticulate, the propodeum more finely, with some fine
longitudinal rugae on the whole basal surface. Sides of the mesonotum
regularly reticulate-punctate, Sides of the pronotum more shining and
of the propodeum longitudinally striate. Petiole finely reticulate;
gaster finely shagreened, almost smooth. The pubescence is rather well
developed on the head, the gaster, and the appendages, sparse on the
thorax. The hairs are very sparse, except around the mouth and at the
tip of the gaster. Head square, with rather convex sides and straight
posterior border. Eyes at the middle of the sides. Frontal area short,
feebly impressed behind. Frontal carinae developed. Clypeus slightly
convex, with rather arched anterior border. Mandibles striate-punctate,
with four blackish teeth. The pronotum forms with the basal surface of
the mesonotum a plane surface with a contour like that of C.
castanea Smith. Sides of the basal surface of the mesonotum blunt,
not marginate, with the anterior eminence scarcely indicated.
Promesonotal suture little or not at all impressed. Sides of the
pronotum marginate. Declivity of mesonotum oblique, feebly concave from
right to left, above with marginate sides. Metanotal furrow moderately
deep. Dorsum of propodeum trapezoidal, its length equal to its width
anteriorly in the small worker. It is convex in front, more feebly
behind. The spines are as short as a fifth of the interval between
their bases, which is concave. They are directed backward and slightly
outward. Declivity as long as two-thirds of the basal surface and
forming with it an angle of about 145°. Petiole trapezoidal, as broad
as long, and as broad as the propodeum. Last antennal joint reddish. A
fine and dense striation disposed as in africana (Mayr) but
more or less effaced on the front, vertex and occiput, where the
reflection is more shining than silky, Propodeum transversely
striate-rugose. Petiole smooth, postpetiole and gaster very finely
shagreened, almost shining. The head is, moreover, punctate as in africana
and much less smooth in the individuals with large head. The head,
which varies in size independently of the rest of the body, which is
almost invariable, is sometimes longer than broad and scarcely
emarginate behind, sometimes broader than long, strongly concave behind
and with convex sides. Eyes more posterior than in africana.
Frontal area narrow, strongly impressed and shining. Mandibles
punctate, feebly striate. Metanotal impression stronger than in africana,
the pronotum less marginate anteriorly. Mesonotum carinate, more
elongate and with the declivous surface much less abrupt than in africana,
with longer propodeal spines, even longer than in the variety variegata
(Mayr) and a little farther apart. Petiole and postpetiole as in africana
(notes sent to Wheeler by Santschi).
Numerous workers taken at the village of Mosekowa between Walikale and
Lubutu by Dr. Bequaert from the peculiar pouches of Macaranga
saccifera (Bequaert, 1922, p Part IV) growing in the Rain Forest.
As only adult ants and no brood were found in the pouches, Dr. Bequaert
does not regard them as true nests. The openings of the pouches were
not closed with fibrous carton. Bequaert (p 454) also recorded them
from stipules of an Uragoga species; and from Barteria
deweverei (p 441).
Bequaert (1922, p
413) found workers of ssp tibialis inside the nectary
containing leaf stipules of Macaranga saccifera at Mosekowa, Zaïre.