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T.F. Houston 
persistently within 30 cm of the ground over the 
nesting area at Kings Park in November and 
December. Occasionally, a male would alight on a 
plant stem and rest for a few seconds to a minute 
before moving on. Males were also observed 
patrolling flowers of Jacksonia sericea. However, no 
male/female encounters were observed at the 
nesting area or the forage plants. 
Associated organisms 
A gasteruptiid wasp, Hyptiogaster arenicola 
Turner, was the only organism found living in 
association with R. maculata. One to a few adults of 
H. arenicola were encountered at the nesting area 
on most visits from 27 November to 6 January. 
Females of this wasp were most often observed 
flying slowly over the nesting area just above the 
ground surface. They followed meandering paths 
and their manner suggested they were searching. 
When an H. arenicola female came close to an open 
burrow entrance of R. maculata it usually circled 
the entrance, all the while continuing to face it with 
antennae directed forward and downward. In most 
cases, after a brief inspection, the wasp would 
alight on a grass stem or some ground litter about 
8-10 cm from the entrance, still facing it, and 
remain motionless. Occasionally, females shifted 
position but remained close to the burrows. On 
one occasion, a female H. arenicola was observed to 
enter a burrow. She had been perching close to the 
burrow entrance for four minutes when a R. 
maculata female arrived and entered the burrow. 
Eight minutes later (perhaps following the 
departure of the burrow occupant, although I did 
not observe this), the H. arenicola female began 
hovering again, moved to the burrow entrance, 
circled it once, alighted, turned 180° and reversed 
down the shaft. In less than 60 seconds, she 
reappeared, moved to a nearby stem where she 
groomed herself and then moved on. 
One female of H. arenicola maintained a vigil near 
a burrow for many minutes but eventually moved 
on without entering it. The occupant of the burrow 
was not sighted during the wasp's vigil and I 
suspect that it is the departure of the host wasp 
from a burrow that stimulates the cleptoparasite to 
enter. 
Further evidence that H. arenicola is 
cleptoparasitic in brood cells of R. maculata came in 
the form of three vacated cocoons found among 
occupied and vacated cocoons of the host. The 
cocoons were easily distinguishable from those of 
the host by being less fibrous and were partly 
composed of a hard blackish material (more so at 
the rear end) that had penetrated between grains 
of sand, forming a coarsely reticulate pattern on 
the outer surfaces of the cocoons (Figure 5B). 
Internally, the cocoons had a smooth, slightly 
shiny, translucent brown layer formed by a hard 
amorphous material laid on a network of coarse 
brown silk fibres. 
DISCUSSION 
Gess and Gess (1992) provided a discussion of 
nesting in the subfamily Masarinae (sensu 
Carpenter 1982) and recognised seven basic nest 
types. Many masarine wasps construct cemented 
earth turrets and/or brood cells using either water 
or nectar as the bonding agent (nest types 1-6). 
One species, Quartinia vagepunctata Schulthess, 
nests in friable soil and constructs entrance turrets 
and brood cells of sand and silk (nest type 7). Nests 
of Rolandia maculata, being made in friable soil and 
having no cemented or bonded earth structures of 
any kind, fit none of the seven nest types and 
require an eighth category. In erecting the genus 
Rolandia (with R. maculata as the type and only 
known species), Richards (1962) remarked that 
"The very marked fringe of bristles on the 
periphery of the lower side of the head, around the 
oral fossa, is perhaps connected with the method 
of gathering food which would be well worth 
studying in life." However, Snelling (1986) noted 
the presence of such bristles in a few genera of 
Masarinae, including Rolandia, and termed them 
'ammochaetae'. He speculated that they may form 
a psammophore, a "basket" for transporting sand 
particles excavated from nests. My observations 
have confirmed (at least for R. maculata) that 
Snelling's view is the correct one. 
ACKNOWLEDGEMENTS 
I am grateful to Mr R. Dixon and the Kings Park 
Board, Perth, for permission to undertake field 
studies in Kings Park. Mr John Jennings of the 
Waite Agricultural Research Institute, Adelaide, 
kindly identified specimens of Hypliogaster arenicola 
and Drs Fred and Sarah Gess, Albany Museum, 
Grahamstown, South Africa, suggested some 
useful literature references. 
REFERENCES 
Carpenter, J.M. (1982). The phylogenetic relationships 
and natural classification of the Vespoidea 
(Hymenoptera). Systematic Entomology 7:11-38. 
Gess, F.W. and Gess, S.K. (1992). Ethology of three 
southern African ground nesting Masarinae, two 
Celonites species and a silk-spinning Quartinia 
species, with a discussion of nesting by the subfamily 
as a whole (Hymenoptera: Vespidae). Journal of 
Hymenoptera Research 1 (1): 145-155. 
Houston, T.F. (1984). Bionomics of a pollen-collecting 
wasp, Paragia tricolor (Hymenoptera: Vespidae: 
Masarinae), in Western Australia. Records of the 
Western Australian Museum 11(2): 141-51. 
Richards, O.W. (1962). A revisional study of the masarid 
