Arboreal ant fauna of Joyama Park, Kagoshima Prefecture, southern Japan

Five tree species (Prunus x yedoensis, Prunus jamasakura, Prunus lannesiana, Quercus acutissima and Acer palmatum) and the associated ant fauna were surveyed in Joyama Park, Hioki City, Kagoshima Prefecture, southern Kyushu, Japan. Ants were found on 206 (92%) of 224 trees surveyed. Fifteen ant species were collected from trees; the three most frequent ant species were Pristomyrmex punctatus (on 92 trees), Crematogaster matsumurai (65 trees) and Formica hayashi (49 trees). The number of ant species found per tree ranged from 0 to 6, with a mean of 1.83±1.11 species. Seven species, Tetramorium nipponense, P. punctatus, Cr. matsumurai, Cr. vagula, Ochetellus glaber, Lasius japonicus and Camponotus vitiosus, nested in trees: in decayed parts. A total of 87 nests were found, on 84 trees (37.5% of all trees surveyed). The nests of Cr. matsumurai were found on 47 (21%) trees. Only three trees had two species nesting together: the respective combinations were Cr. matsumurai and C. vitiosus, T. nipponense and P. punctatus, and C. vitiosus and Cr. vagula. Among the 15 ant species found on the trees, only four (26.7%) were principally arboreal nesters, and two of the most frequent species (P. punctatus and F. hayashi) were principally ground nesters.