Diversity of plants used for nest-building by Cheiracanthium japonicum (Araneae: Miturgidae)

抄録

The taxonomic diversity and biological features of plant species used for nest-building by the Japanese foliage spider Cheiracanthium japonicum were examined. The spider builds three types of nests in its life cycle, namely, for molting, mating, and breeding, using a plant leaf. In total, 23 plant species of 21 genera in seven families were recorded as plants used by C. japonicum. Twenty species among the 23 species were recorded for the first time. Most of these plants were classified in the families Poaceae and Asteraceae. The number of plant species was the highest for the molting nest and the lowest for the breeding nest. As nest types changed from molting to breeding, the number of plant species used for nest-building decreased sharply, and adult female spiders used poaceous plants almost exclusively to build a breeding nest because their leaves are larger and longer than those of the other plant taxa. Of the three types of nests, the breeding nest was barrel-shaped, and the poaceous species was considered to be the most suitable for C. japonicum to build a barrel-shaped breeding nest.