Ambrosia beetles are beetles of the weevil subfamilies Scolytinae and Platypodinae, which live in nutritional symbiosis with ambrosia fungi. The beetles excavate tunnels in dead or stressed trees into which they introduce fungal gardens, their sole source of nutrition. After landing on a suitable tree, an ambrosia beetle excavates a tunnel in which it releases its fungal symbiont. The fungus penetrates the plant's xylem tissue, extracts nutrients from it, and concentrates the nutrients on and near the surface of the beetle gallery. Ambrosia fungi are typically poor wood degraders, and instead utilize less demanding nutrients. Symbiotic fungi produce and detoxify ethanol, which is an attractant for ambrosia beetles and likely prevents growth of antagonistic pathogens and selects for other beneficial symbionts. The majority of ambrosia beetles colonize xylem of recently dead trees, but some colonize stressed trees that are still alive, and a few species attack healthy trees. Species differ in their preference for different parts of trees, different stages of deterioration, and in the shape of their tunnels ("galleries"). However, the majority of ambrosia beetles are not specialized to any taxonomic group of hosts, unlike most phytophagous organisms including the closely related bark beetles. One species of ambrosia beetle, Austroplatypus incompertus exhibits eusociality, one of the few organisms outside of Hymenoptera and Isoptera to do so.
A bark beetle is the common name for the subfamily of beetles Scolytinae. Previously, this was considered a distinct family (Scolytidae), but is now understood to be a specialized clade of the "true weevil" family (Curculionidae). Although the term "bark beetle" refers to the fact that many species feed in the inner bark (phloem) layer of trees, the subfamily also has many species with other lifestyles, including some that bore into wood, feed in fruit and seeds, or tunnel into herbaceous plants. Well-known species are members of the type genus Scolytus, namely the European elm bark beetle S. multistriatus and the large elm bark beetle S. scolytus, which like the American elm bark beetle Hylurgopinus rufipes, transmit Dutch elm disease fungi (Ophiostoma). The mountain pine beetle Dendroctonus ponderosae, southern pine beetle Dendroctonus frontalis, and their near relatives are major pests of conifer forests in North America. A similarly aggressive species in Europe is the spruce ips Ips typographus. A tiny bark beetle, the coffee berry borer, Hypothenemus hampei is a major pest on coffee plantations around the world.
Verbenone is a natural organic compound classified as a terpene that is found naturally in a variety of plants. The chemical has a pleasant characteristic odor. Besides being a natural constituent of plants, it and its analogs are insect pheromones. In particular, verbenone when formulated in a long-lasting matrix has an important role in the control of bark beetles such as the mountain pine beetle and the Southern pine bark beetle.
Sassafras albidum is a species of Sassafras native to eastern North America, from southern Maine and southern Ontario west to Iowa, and south to central Florida and eastern Texas. It occurs throughout the eastern deciduous forest habitat type, at altitudes of up to 1,500 m (4,900 ft) above sea level. It formerly also occurred in southern Wisconsin, but is extirpated there as a native tree.
Persea palustris, also known as swamp bay or swampbay, is a small tree or shrub found throughout the Southeastern United States and the Bahamas, with much of its range overlapping with that of its relative Persea borbonia. It is generally not more than 40 feet tall, with bark separated into scales by fissures across its surface. Mature leaves are green, paler on their undersides, which have prominent brownish or reddish-brown hairs. The species prefers swamps and coastal areas, particularly locations with moist, peat-rich soil. It is sensitive to the fungal disease known as laurel wilt, even more so than related species.
Laurel wilt, also called laurel wilt disease, is a vascular disease that is caused by the fungus Raffaelea lauricola, which is transmitted by the invasive redbay ambrosia beetle, Xyleborus glabratus. The disease affects and kills members of the laurel family. The avocado is perhaps the most commercially valuable plant affected by laurel wilt.
Ips is a genus of beetles in the family Curculionidae, the true weevils. They are bark beetles, members of the subfamily Scolytinae. Species are distributed throughout the Northern Hemisphere. Some are known as introduced species in Australia and Africa. Many species are pests of forest trees, especially pines and spruces. They are known commonly as engraver beetles, ips engraver beetles, and pine engravers.
Japanese oak wilt is a fungal disease caused by Raffaelea quercivora fungus affecting by oak trees. In 1998, Japanese plant pathologists group was isolation, inoculation and reisolation the dead tree. It is the first disease known that Raffaela fungus cause plant disease.
Raffaelea fusca is a mycangial fungus, first isolated from female adults of the redbay ambrosia beetle, Xyleborus glabratus.
Raffaelea ellipticospora is a mycangial fungus, first isolated from female adults of the redbay ambrosia beetle, Xyleborus glabratus.
Raffaelea subalba is a mycangial fungus, first isolated from female adults of the redbay ambrosia beetle, Xyleborus glabratus.
Raffaelea is a genus of ambrosia fungi in the family Ophiostomataceae. It was circumscribed by mycologists Josef Adolph von Arx and Grégoire L. Hennebert in 1965 with Raffaelea ambrosiae as the type species. The genus is named in honor of Italian botanist Raffaele Ciferri.
Euwallacea fornicatus, also known as tea shot-hole borer, or polyphagous shot-hole borer (PSHB) is a species complex consisting of multiple cryptic species of ambrosia beetles known as an invasive species in California, Israel, South Africa, and Australia. The species has also been unintentionally introduced into exotic greenhouses in several European countries.
Xyleborus affinis, the sugarcane shot-hole borer, is a species of ambrosia beetle in the family Curculionidae. It is found on all continents with woodlands and is one of the most widespread ambrosia beetles internationally, primarily in areas with humid tropical climates like Florida. Like other ambrosia beetles, Xyleborus affinis is attracted to dead fallen logs in early stages of decay. Due to the presence of X. affinis on moist timber, this species is mistakenly believed to be the cause of tree death. However, there is insufficient evidence to support their presence as a causal factor. Rather, these beetles are believed to target and accelerate the decay process of trees that are already deteriorated and weak.
Xylosandrus germanus, known generally as the alnus ambrosia beetle or black stem borer, is a species of ambrosia beetle in the family Curculionidae. X. germanus poses challenges in woody ornamental species and orchard crops such as apples and pecan. Furthermore, X. germanus is recognized or suspected to act as a vector for plant pathogens to varying extents, potentially leading to the decline of trees. The black stem borer is native to eastern Asia, but is an invasive species in Europe and North America. This species carries and feeds on associated ambrosia fungus, Ambrosiella grosmanniae.
Xyleborinus saxesenii, commonly known as the fruit-tree pinhole borer, is a species of ambrosia beetle in the family Curculionidae. It is native to the Palaearctic region but has been introduced in many locations, including North America. X. saxesenii typically live in freshly dead wood, but it has also been reported to attack live trees. Such attacks on live trees may lead to economic damage.
Xyleborus dispar is a species of bark beetle commonly called the Pear blight beetle, or the European shothole borer. It is an invasive species in North America, and can be a pest in orchards and forests throughout its range.
Ambrosiella roeperi is the fungal symbiont of the granulate ambrosia beetle, Xylosandrus crassiusculus, facilitating this insect’s capacity to accumulate on and damage a diverse array of woody plants from around the world. It is one of several important nutritional partners derived from order Microascales that sustain and are transported by xylomycetophagous scolytine beetles.
Euwallacea validus is a species of Euwallacea beetle native to Asia. The beetle species was discovered in Long Island, New York in 1975. Like other Euwallacea species beetles, E. validus is known for its mutualistic symbiotic relationship with fungi, acting as a vector for Fusarium oligoseptatum and Raffaelea subfusca, often using Tree of Heaven as a preferred host. Out of the five confirmed species of Euwallacea spp. in the United States, E. validus is the most widespread and longest established, yet much about their second fungal partner, Raffaelea subfusca, is not known.
