Introduction - Synonymy - Distribution - Description - Biology - Hosts - Economic Importance - Management - Selected References
In January 1967, specimens of a wood boring beetle were collected in oak lumber at Ft. Lauderdale, Florida and forwarded for identification to the Department of Entomology, University of Florida. These were later sent to the Division of Plant Industry and identified by the senior author as Heterobostrychus aequalis (Waterhouse), a species not previously known to be established in the United States (Fisher 1950).
Since this species is a serious pest of lumber and nearly all wood products, a survey was immediately conducted by the Division of Plant Industry and the U.S. Department of Agriculture to determine the extent of the infestation. Subsequent inspections of lumber yards revealed additional infestations in the Ft. Lauderdale and Miami areas. In 2001, specimens were found infesting pallets and containers of machine parts imported from Singapore in St. Petersburg, Pinellas County, Florida (Halbert 2001).
Sixty-four species of the family Bostrichidae are recorded for the U.S. and Canada (Arnett 2000), and twenty-nine additional species have been intercepted, but they have not become established (Fisher 1950). The genus Heterobostrychus contains only one other species, brunneus (Murray), that has been intercepted in the U.S, both in Florida (Arnett 2000). It differs from aequalis in the lack of hook-like tubercles at the apical declivity in the male and in the presence of short recumbent pubescence on the dorsal surface.
The elytra are nearly tubular in shape until the posterior 1/10 where they abruptly descend to the abdomen. This area, called the apical declivity, is somewhat excavated and variable between the sexes; the males possess two incurved, hook-like projections (not send in the female) as well as an additional smaller, highly variable, tubercle near the sides. The surface is densely, deeply punctate, with the punctures arranged in fairly distinct rows, but somewhat variable in shape and extent, especially near the apical declivity.
Larva: The larva is white to yellowish, with a characteristic bostrichid shape, variable in size with most last instars averaging 10 mm. The mandibles are black, conical and the darkest area on the larva. The setation is sparse and pale, and not readily visible to the unaided eye. The antenna is shown in the figure below. The epipharynx possesses posterior projections and a characteristic setal pattern. The maxilla is shown in the figure below.
The eggs are deposited on rough surfaces of sawed lumber and logs, in holes, cracks or short tunnels made by the female. The larval borings may be 1/4 inch wide, winding for several inches. The tunnels are usually filled with tightly packed, fine, sawdust-like material which is characteristic of this genus. Tunnels of most pinhole and shothole borers contain very little such material. Pupation occurs in a cell at the end of the tunnel.
The adult emerges through an exit hole, often after chewing through a few inches of wood. Length of development from egg to adult is variable from one to several years (up to six years recorded). Apparently they can survive under dry conditions present in manufactured wood products and emerge several years later, as do some of the Cerambycidae.
Author: Robert E. Woodruff, Florida Department of Agriculture and Consumer Services, Division of Plant Industry; and Thomas R. Fasulo, University of Florida
Originally published as DPI Entomology Circular 58. Updated for this publication.
Photographs: Lyle J. Buss, University of Florida
Illustration: FDACS-DPI
Project Coordinator: Thomas R. Fasulo, University of Florida
Publication Number: EENY-364
Publication Date: January 2006
Copyright 2006 University of Florida
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adult male
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