94 
Psyche 
[Vol. 88 
Table 2. Nest site records for the Rhytidoponera impressa group, excluding small, 
incipient colonies (< 20 workers). Figures in parentheses represent the percentages 
(for each species) of colonies occupying a given type of nest site. 
Species 
Rotten 
Logs 
Stones 
Fallen 
Epiphytes 
Total 
confusa 
258 
143 
11 
412 
(62.6) 
(34.7) 
(2.7) 
chalybaea 
145 
19 
1 
165 
(87.9) 
(11.5) 
(0.6) 
impressa 
13 
1 
0 
14 
(92.9) 
(7.1) 
(0.0) 
purpurea 
34 
0 
0 
34 
(100.0) 
(0.0) 
(0.0) 
enigmatica 
0 
21 
0 
21 
(0.0) 
(100.0) 
(0.0) 
all species 
450 
(69.7) 
184 
(28.5) 
12 
(1.9) 
646 
R. enigmatica is a localized species, known only from wet 
sclerophyll vegetation in sandstone gullies (6 sites, including two 
ANIC records) and urban parkland (1 site), the latter record coming 
from an area where the original habitat would have been sandstone 
gully vegetation. The range of elevation from which it has been 
recorded is 10 to 180 meters. Thus, with regard to habitat preference 
enigmatica is the most stenotopic species. Most of the known 
populations are in sympatry with, or in close proximity to, 
populations of confusa and/or chalybaea. 
The 7 impressa populations studied come from tropical rainforest 
(1), subtropical rainforest (5), and dry rainforest (1). These data, 
along with 30 other collection records in the ANIC, indicate that 
impressa is confined to Queensland rainforest at altitudes ranging 
from 30m to 1050m. 
Based on the 12 populations studied here plus additional records 
from the ANIC and from Wilson (1958), purpurea is recorded from 
subtropical and tropical rainforest (and one population from dry 
microphyll rainforest on the Mt. Windsor Tableland) in northern 
Queensland (30m to 1200m), and from tropical montane rainforest 
(600m to 1300m) in Papua New Guinea. In north Queensland it 
occurs in both primary-growth and partially disturbed rainforest, 
