Xyleborus

ambrosia beetles, bark beetles

Species Guides

Xyleborus affinis(sugarcane shot-hole borer)
Xyleborus bispinatus
Xyleborus celsus(Hickory Timber Beetle)
Xyleborus ferrugineus
Xyleborus glabratus(Redbay Ambrosia Beetle)
Xyleborus horridus
Xyleborus impressus
Xyleborus intrusus
Xyleborus pfeili

Xyleborus is a of ambrosia beetles in the Curculionidae ( Scolytinae). These small wood-boring beetles are characterized by their obligate symbiotic relationship with ambrosia fungi, which they cultivate in galleries carved into trees and use as their primary food source. Several have become significant pests, including Xyleborus glabratus (redbay ), which the fungus causing laurel wilt . The genus includes both native and introduced species with varying degrees of host specificity.

Xyleborus by no rights reserved, uploaded by cgmayers. Used under a CC0 license.

Xyleborus glabratus by no rights reserved, uploaded by cgmayers. Used under a CC0 license.

Xyleborus affinis by (c) Arturo Santos, some rights reserved (CC BY), uploaded by Arturo Santos. Used under a CC-BY license.

Pronunciation

How to pronounce Xyleborus: //zaɪˈlɛbərəs//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Habitat

Woody substrates; occupy various including living trees, dead wood, and roots. X. glabratus colonizes trees in Lauraceae. X. germanus bores into tea roots at approximately 30 cm depth. X. compactus occupies tea twigs 5–8 mm in diameter.

Distribution

Native range centered in Asia; multiple introduced globally. X. glabratus: native to Southeast Asia, introduced to Georgia (USA) in 2002, established in nine southeastern US states with potential for further spread to California, Mexico, and American tropics. X. ferrugineus and X. volvulus: present in Mexico with extensive climatically suitable areas in Chiapas, Tamaulipas, Veracruz, and Jalisco. X. fornicatus: recorded across Asia (Bangladesh, India, Indonesia, Malaysia, Philippines, Sri Lanka, Taiwan, Vietnam), Africa (Madagascar, Réunion), and Pacific islands (Fiji, Hawaii, Papua New Guinea, Solomon Islands).

Diet

Ambrosia fungi cultivated on gallery walls; larvae feed on fungal spores and mycelia. Not wood-feeders; xylomycetophagous.

Life Cycle

Overwinters as . X. germanus and X. compactus: two per year. X. germanus generations occur June–early July and late August–September. X. compactus generations occur late July–late August and late August–September. Optimal rearing temperature 21–23°C for X. germanus, 25–27°C for X. compactus.

Behavior

Females initiate gallery formation and carry fungal spores in specialized mycangia (internal fungus-storing organs). Cultivates ambrosia fungi on gallery walls for larval nutrition. X. glabratus females Raffaelea lauricola, the causal agent of laurel wilt . No known for X. glabratus; primary attractants are volatile terpenoid from Lauraceae.

Ecological Role

Decomposers of woody material in native ; nutrient cyclers through fungal . act as of plant pathogenic fungi, causing tree mortality and forest ecosystem disruption. X. glabratus has caused extensive mortality in native Persea and threatens avocado production.

Human Relevance

Several are significant agricultural and forestry pests. X. glabratus threatens $65 million Florida avocado crop and native Lauraceae forests. X. compactus and X. germanus are pests of tea plantations in Asia. incur substantial management costs; detection programs for X. glabratus use lures (phoebe oil, manuka oil, cubeb oil, and (-)-α-copaene enriched ).