Xylosandrus compactus
Xylosandrus compactus is a species of ambrosia beetle. Common names for this beetle include black twig borer, black coffee borer, black coffee twig borer and tea stem borer. The adult beetle is dark brown or black and inconspicuous; it bores into a twig of a host plant and lays its eggs, and the larvae create further tunnels through the plant tissues. These beetles are agricultural pests that damage the shoots of such crops as coffee, tea, cocoa and avocado.
Description
This beetle is dark brown or black. The adult female is up to long and about half as wide. The head is convex at the front with an indistinct transverse groove above the mouthparts. Each antenna consists of a funicle with five segments and an obliquely truncated club slightly longer than it is wide. The pronotum is rounded with six or eight serrations on the front edge. The elytra are convex and grooved and have fine perforations, and there are bristles between the grooves. The adult male is a smaller insect, has an unserrated pronotum and no wings.The eggs are smooth, white and ovoid, about long. The larvae are creamy white with brownish heads and have no legs. The pupae are cream-coloured and exarate.
Distribution
Xylosandrus compactus has a wide distribution in the tropics. Its range extends from Madagascar and much of tropical Africa, through Sri Lanka and southern India, Thailand, Vietnam, Malaysia, China and Japan to Indonesia, New Guinea and various islands in the Pacific. It was introduced into the continental United States in 1941 and has also spread to Brazil and Cuba. It arrived in Hawaii in 1961, and here it infests over one hundred species of timber trees, fruit trees, ornamental trees and fruit bushes. Its presence in Hawaii is putting some rare and threatened endemic trees such as Alectryon macrococcus, Colubrina oppositifolia, Caesalpinia kavaiensis, and Flueggea neowawraea, at risk.In 2011, Xylosandrus compactus was first detected in Europe in Portici and Naples, likely introduced through the international trade of nursery plants. Since then, within a few years, it has spread along the Tyrrhenian coast, subsequently reaching the northern inland areas, and finally the Adriatic coast. In 2015, the species expanded from Liguria to France, and in 2019 it was recorded in Spain on a carob tree, which was promptly treated in an attempt to eradicate the beetle. In July of the same year, X. compactus was also found in southern Greece infesting carob, laurel, olive, Judas tree, and shrubs of the genus Rhamnus, thereby becoming a concern at the European level. By 2025, it had become invasive in Perth, Western Australia.