1970] 
Brown, Gotwald & Levieux — Ants 
271 
the annually-burned savanna (by Levieux) has failed to turn up any 
samples of the new species, either as colonies or as single foraging 
workers. Apomyrma and the 5 or 6 Amblyopone species also found 
here constitute a remarkable and unexpected cryptic soil faunule, 
some members, perhaps all, of which belong to a centipede-feeding 
guild. This assemblage was revealed only by systematic large scale 
excavation and sifting of the soil in the course of intensive studies 
of savanna ant ecology conducted since 1962 at Lamto. 
Like the Amblyopone species at Lamto, Apomyrma stygia is prob- 
ably best considered as an invader of the savanna via the gallery 
forest from the more extensive rain forest belt to the south. So far, 
excavations like those completed at Lamto have not been made in the 
rain forest proper, and have been made only to a limited extent in 
gallery forest. Apomyrma , like many of the other subterranean 
predatory ponerines, moves deep (30 cm or more) into the soil 
during the dry season (October to April), but during the rainy 
season it comes up to within 10 cm of the surface. 
The 4 nests of A. stygia were all found during April-June 1968. 
Nos. AA 315 Ni and AA 318 Ni (both May 1968) were taken 
in sandy alluvial soil of the gallery forest of the Bandama River. 
The soil surface in each case, while tree-shaded, was bare of herbage. 
AA 315 Ni, a nest of nest fragment of the large form consisting of 
32 workers and a single dealate queen, was taken about 10 cm deep, 
and was found in the same meter quadrat as Amblyopone sp. near 
normandi. AA 318 Ni, 15 workers and a dealate queen, was found 
about 15 cm beneath the surface and in the same meter quadrat as 
a colony of Amblyopone mutica. 
The type nest (without code number) was taken 17 June 1968; 
it and AA 285 N8 came from unburned savanna with dark clayey 
“terre noire” soil bearing a cover of the grass Loudetia simplex 
growing about 1 m high. The nest contained about 75 workers, 
6 alate and 15 dealate queens, 2 ergatoids, and a few pupae and 
pharate adults of queens, males and workers, plus a few larvae of 
different sizes. 
The type nest was 15-20 cm in diameter and 2 cm high, containing 
the brood, most of the adults, and cut-up remains of a geophilomorph 
Figures 13-17, Apomyrma stygia sp. n., small form, antenna and mouth- 
parts of worker. Fig. 13, antenna. Fig. 14, labrum, external view. Fig. 15, 
right mandible, dorsal view. Fig. 16, left maxilla, external view; the 
maxillary comb has been drawn as seen through the transparent galea. 
Fig. 17, labium with left labial palpus, lateral view. 
