Treeholes as larval habitat of the dragonfly Hadrothemis camarensis (Odonata: Libellulidae) in Kakamega forest, Kenya

Larvae of the anisopteran odonate Hadrothemis camarensis (Kirby) were found in water-containing treeholes, but not elsewhere, in Kakamega Forest, western Kenya, in a site where no ground pools were detected. Treeholes were sampled by siphoning water with wide-bore, flexible plastic tubing. Larvae were found during four consecutive years of sampling in 46% of treeholes (N=54), and in 26% of treehole samples (N=205). Larvae were more likely to be found in treeholes during wetter months. Distribution of larvae among treeholes was clumped. Larvae occurred more often in treeholes: of larger surface area and gape size, attributes that correlated positively with median water volume; of larger volume, within the range 0.15-42 1; and higher above the forest floor, up to 22.45 m. Larvae of Chironomidae and Culicidae predominated numerically among prey of odonate larvae, smaller larvae preying more on the former and larger larvae more on the latter. No cannibalism among odonate larvae was detected.