Observations on the biology of some tropical rain forest Scolytidae (Coleo-ptera) from Fiji: I. Subfamilies—Hylesininae, Ipinae (excluding xyleborini)

Abstract

AbstractThe biology of seventeen common species of rain forest bark beetles was studied during a six month visit to Fiji in 1973. Geographical and altitude ranges, and host plants are given; breeding galleries and brood composition are described in detail, and the significance of competitors, associates, and parasites is noted. The biology of an Ozodendron sp. is described for the first time, and of Cryphalomorphus sp. for the first time outside Africa. Most Fijian bark beetles show strong host preferences, and some of the most common endemics, such as Cryphalomorphus grosse-punctatus Browne, Hypocryphalus laticollis Browne and Ozodendron fijianus (Schedl) are apparently host specific. Among dominant trees of the rain forest only Myrtaceae and conifers (Dacrydium, Podocarpus), which are thin barked, are apparently free of bark beetles. Of note among biological features is the habit, not previously recorded for tropical bark beetles, of packing the egg galleries with frass after egg-laying has finished. Five species are potential pests of pines—Cryphalus variolosus Schedl, Cyrtogenius granulifer (Beeson), Ozodendron fijianus (Schedl), Poecilips cyperi (Beeson), P. fijianus Schedl. All were taken in endemic Pinaceae, and some in Pinus plantations as well. Lying within the tropical hurricane belt, living coniferous exotics in Fiji are potentially vulnerable to bark beetle attack when trees are under stress, as often occurs in the dry season.