Pin- and Shot-Hole Borers, Ambrosia Beetles

(Coleoptera: Scolytidae and Platypodidae)

(2) Distinctive Features of Scolytidae and Platypodidae

go to main menu


This article is divided into the following headings:


Distinctive Features of Scolytidae and Platypodidae

Pin- and shot-hole borers belong to the two closely related families Scolytidae and Platypodidae. Their name comes from the fact that the beetles bore small pin-holes or larger shot-holes between 0.5 and 3 mm in the wood of living or dying trees as well as in unseasoned timber products. Common are the platypodid genera Crossotarsus, Diapus and Platypus and the scolytids Xyleborus, Webbia pabo, Hylurdrectonus piniarius, Poecilips and Arixyleborus canaliculatus. There is a variety of host species like Araucaria cunninghamii, A. hunsteinii, Tectona grandis, Acacia spp., Eucalyptus deglupta, Calophyllum spp. and Terminalia brassii. Pin- and shot-hole borers cause considerable degradation of wood and timber in PNG, worth about one million Kina per year. Although the bore holes are relatively quickly covered up by growing bark, the galleries will still remain in the wood, decreasing its quality or even making it unsuitable for veneer and ply wood. Often the galleries are penetrated and stained by fungi. In the case of rot, the stability of the timber is decreased so that it is unusable for particular purposes. Apart from that, the presence of pin- and shot-hole borers in timber bound for export can cause serious quarantine problems and result in the rejection of a log shipment.

Feature Scolytidae Platypodidae
common name bark beetles and ambrosia beetles or pin- and shot-hole borers ambrosia beetles or pin- and shot hole-borers
colour of adults reddish, black or light to brown dark light to dark brown
size of adults 1 - 6 mm 2 to several mm
shape of adults cylindrical, slender or stocky in build, with reduced, bowl-shaped prothorax elongate, less cylindrical, sometimes flattened above
colour of larvae creamy white creamy white
shape of larvae slightly curved, more stocky in build curved with humped thorax
size of hole in wood smaller holes, sometimes with resin or long frass pellet slightly larger hole often with discharged powdery frass
duration of life cycle 4 weeks to several months 4 weeks to 12 months

Distinctive features of Scolytidae and Platypodidae

 

Pin- and Shot-Hole Borers: (left) Crossotarsus porcatus (Platypodidae); (centre) Platypus jansoni (Platypodidae); (right) Xyleborus destruens (Scolytidae)

 

Pin- and Shot-Hole Borer Damage: galleries made by Crossotarsus spp.; (left) Xyleborus spp.; (right top) Platypus spp. (right bottom) (reproduced from Roberts, H., 1987)


go to previous page
go to
general info on coleopteran pests
go to
fire
go to
host trees and their pests
go to
glossary
go to
main menu

Michael F. Schneider, 1999