Scolytinae
Guides
Xyleborinus artestriatus
Xyleborinus artestriatus is a species of ambrosia beetle in the subfamily Scolytinae. Like other members of its genus, it is a fungus-farming beetle that excavates galleries in wood and cultivates symbiotic fungi for larval nutrition. The species has been recorded in North America, Australia, Oceania, and Southern Asia. Its specific ecological role and host associations remain poorly documented compared to better-studied congeners such as Xyleborinus saxesenii.
Xyleborinus attenuatus
Xyleborinus attenuatus is an invasive ambrosia beetle native to East Asia that has established throughout Europe and North America. As a member of the subfamily Scolytinae, it cultivates symbiotic ambrosia fungi within galleries excavated in wood, feeding on the fungal growth rather than the wood itself. In Central Europe, it completes one generation annually with flight activity occurring from mid-March to May and F1 adults emerging in August and September. It predominantly colonizes soft deciduous trees and has not been reported to cause significant economic damage, though it vectors multiple ambrosia fungi species.
Xyleborinus gracilis
Xyleborinus gracilis is a species of ambrosia beetle in the family Curculionidae, subfamily Scolytinae. It was described by Wood & Bright in 1992. As a member of the ambrosia beetle tribe Xyleborini, it engages in fungus-farming behavior, excavating galleries in wood and cultivating symbiotic fungi as a food source for its larvae. The species has been documented across multiple continents including North America, South America, Africa, the Caribbean, and Middle America.
Xyleborinus saxesenii
fruit-tree pinhole borer, Keyhole Ambrosia Beetle
Xyleborinus saxesenii is a small ambrosia beetle native to the Palaearctic region that has become one of the most widespread invasive ambrosia beetles globally. It exhibits facultative eusociality with cooperative breeding, where adult daughters delay dispersal to assist with brood care, fungus farming, and nest maintenance. The species cultivates Raffaelea sulphurea as its primary fungal mutualist, though it has been observed to feed on wood tissue as well, making it xylomycetophagous. It primarily colonizes dead or dying wood but has been documented attacking live trees, including economically important species such as chestnut and apple, causing concern in forestry and orchard management.
Xyleborus
ambrosia beetles, bark beetles
Xyleborus is a genus of ambrosia beetles in the family Curculionidae (subfamily Scolytinae). These small wood-boring beetles are characterized by their obligate symbiotic relationship with ambrosia fungi, which they cultivate in galleries carved into host trees and use as their primary food source. Several species have become significant invasive pests, including Xyleborus glabratus (redbay ambrosia beetle), which vectors the fungus causing laurel wilt disease. The genus includes both native and introduced species with varying degrees of host specificity.
Xyleborus affinis
sugarcane shot-hole borer
Xyleborus affinis is a highly widespread ambrosia beetle native to the American tropics, now found in tropical and subtropical regions worldwide. It cultivates symbiotic fungi in galleries bored into decaying wood, feeding exclusively on these fungal gardens. The species exhibits facultative eusociality with delayed dispersal of adult offspring, who assist with nest maintenance and brood care. Females are the dispersing sex and are strongly attracted to ethanol and specific host plant volatiles. Despite frequent association with declining trees, it primarily colonizes wood already in early decay rather than causing primary mortality.
Xyleborus celsus
Hickory Timber Beetle
Xyleborus celsus, commonly known as the hickory timber beetle, is a bivoltine ambrosia beetle native to North America. It specializes in colonizing stressed or dying black hickory trees (Carya texana) and other hickory species. The species overwinters as adults and completes development from egg to adult in approximately 35 days. Unlike some invasive congenerics, it appears to be a native primary colonizer of weakened trees rather than an aggressive killer of healthy hosts.
Xyleborus ferrugineus
Xyleborus ferrugineus is an ambrosia beetle (subfamily Scolytinae) that cultivates symbiotic fungi for nutrition rather than feeding directly on wood. Females bore into host trees to create galleries where they farm ambrosia fungi, which serve as the sole food source for adults and larvae. The species exhibits strong sexual dimorphism, with females being larger, more numerous, and solely responsible for gallery formation and colony founding. It has been documented as a potential vector of Ceratocystis cacaofunesta, the causal agent of lethal wilt disease in cocoa.
Xyleborus impressus
Xyleborus impressus is a species of ambrosia beetle in the family Curculionidae, first described by Eichhoff in 1868. As a member of the genus Xyleborus, it exhibits the characteristic fungus-farming behavior of ambrosia beetles, cultivating symbiotic fungi within wood galleries. The species has been documented in both North and South America. Like other ambrosia beetles, it is a wood-boring insect that lives most of its life concealed within host trees.
Xyleborus pfeili
Xyleborus pfeili is an ambrosia beetle in the subfamily Scolytinae, native to regions including Europe and Asia. Like other ambrosia beetles, it cultivates symbiotic fungi within wood tunnels as its primary food source. Laboratory studies have documented its reproduction on semi-artificial diets, revealing arrhenotokous parthenogenesis where unmated females produce only male offspring. The species has been successfully reared using sawdust-based diets with fungal symbionts, providing a model for studying ambrosia beetle biology.
Xyleborus pubescens
Xyleborus pubescens is a species of bark beetle in the weevil family Curculionidae. First described by Zimmermann in 1868, this small wood-boring beetle belongs to a genus known for fungus-farming behavior, where beetles cultivate symbiotic fungi in tunnels they excavate within wood. The species occurs in North America, with records extending from the Caribbean through Middle America to Canada, including Ontario.
Xyleborus viduus
Xyleborus viduus is a species of bark beetle in the family Curculionidae, first described by Eichhoff in 1878. It is native to North America and belongs to a genus containing numerous ambrosia and bark beetle species, many of which are economically significant forest pests. The species is provisionally accepted in taxonomic databases, indicating some uncertainty regarding its current classification status.
Xyleborus xylographus
Xyleborus xylographus is a species of bark beetle in the family Curculionidae, first described by Thomas Say in 1826. It belongs to the tribe Xyleborini, which includes ambrosia beetles that cultivate symbiotic fungi in wood galleries. The species has been recorded in North America, the Caribbean, and Southern Asia. Like other members of its genus, it likely engages in fungus-farming behavior, though specific ecological details for this species remain limited in published literature.
Xylosandrus
Xylosandrus is a genus of ambrosia beetles in the subfamily Scolytinae, family Curculionidae, containing approximately 54 species globally. The type species is Xyleborus morigerus (Blandford, 1894). Species in this genus are fungus-farming beetles that excavate gallery chambers in wood, introduce symbiotic fungi, and feed on fungal growth rather than wood tissue. Several species, including X. crassiusculus and X. germanus, have become invasive pests of ornamental and fruit trees in North America and elsewhere.
Xylosandrus amputatus
Xylosandrus amputatus is a species of ambrosia beetle in the weevil family Curculionidae, subfamily Scolytinae. The species has been used as a model organism in studies of mycangial structure, with micro-CT scanning revealing detailed three-dimensional anatomy of its fungus-storing organs. It is known from North America and Southern Asia. Like other ambrosia beetles in the genus, it engages in obligate mutualism with fungi, carrying symbionts in specialized internal structures called mycangia.
Xylosandrus compactus
black twig borer, black coffee borer, black coffee twig borer, tea stem borer
Xylosandrus compactus is a highly invasive ambrosia beetle (Scolytinae) native to subtropical Asia. Females tunnel into twigs of living woody plants, cultivate symbiotic fungi as larval food, and reproduce through arrhenotokous parthenogenesis. The species has spread to over 50 countries, becoming a significant agricultural pest of coffee, tea, cocoa, and avocado, and threatening native forest ecosystems in invaded regions.
Xylosandrus crassiusculus
Granulate Ambrosia Beetle, Asian Ambrosia Beetle
Xylosandrus crassiusculus is a small ambrosia beetle native to tropical and subtropical Asia that has become one of the most successful invasive wood-boring beetles globally. Adults are reddish-brown, 2–3 mm long, and exhibit a specialized fungus-farming mutualism. Females excavate galleries in wood, introduce the symbiotic fungus Ambrosiella roeperi, and cultivate it as the sole food source for themselves and their offspring. The species is polyphagous on broadleaf trees and shrubs, infesting stressed nursery stock, young trees, and stacked timber, causing economic damage in forestry and agriculture.
Xyloterini
Xyloterini is a tribe of ambrosia beetles within the subfamily Scolytinae (Curculionidae). Members are characterized by fungal cultivation behavior and association with woody host plants. The tribe includes genera such as Xyloterinus and Indocryphalus. Xyloterinus politus, the type species of Xyloterinus, attacks black oak trees and maintains mutualistic relationships with ambrosia yeasts including Candida xyloterini, a yeast species named after this beetle tribe.
Xyloterinus politus
Polished Bark Beetle
Xyloterinus politus is a North American ambrosia beetle in the family Curculionidae, historically placed in Scolytidae. It is the sole species in the monotypic genus Xyloterinus. The species exhibits obligate mutualism with cultivated fungi, excavating galleries in hardwood and softwood trees where it grows and feeds on ambrosial fungi rather than wood tissue. Females initiate gallery construction and maintain fungal gardens; males do not excavate galleries and are excluded from active attacks. The beetle overwinters as an adult in old galleries and cradles.