''Tetropium fuscum'', the brown spruce longhorn beetle, is a species of

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

in the family

Cerambycidae The longhorn beetles (Cerambycidae), also known as long-horned or longicorns (whose larvae are often referred to as roundheaded borers), are a large family of beetles, with over 35,000 species described. Most species are characterized by anten ...

.Bezark, Larry G
''A Photographic Catalog of the Cerambycidae of the World''
Retrieved 7 July 2012. It was described by

Johan Christian Fabricius Johann Christian Fabricius (7 January 1745 – 3 March 1808) was a Danish zoologist, specialising in "Insecta", which at that time included all arthropods: insects, arachnids, crustaceans and others. He was a student of Carl Linnaeus, and is co ...

in 1787. ''Tetropium fuscum'' is native to Europe and Northern Asia, and has been introduced to

Nova Scotia Nova Scotia is a Provinces and territories of Canada, province of Canada, located on its east coast. It is one of the three Maritime Canada, Maritime provinces and Population of Canada by province and territory, most populous province in Atlan ...

, Canada. Brown spruce longhorn is a pest of

spruce A spruce is a tree of the genus ''Picea'' ( ), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ecosystem, boreal (taiga) regions of the Northern hemisphere. ''Picea'' ...

trees.

Distribution

Brown spruce longhorn beetle is native to

Continental Europe Continental Europe or mainland Europe is the contiguous mainland of Europe, excluding its surrounding islands. It can also be referred to ambiguously as the European continent, – which can conversely mean the whole of Europe – and, by som ...

and parts of

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

has been recorded in the following countries: Austria, Belarus, Belgium, Bosnia-Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Italy, Japan, Kazakhstan, Latvia, Lithuania, Moldova, Montenegro, Netherlands, Norway, Poland, Romania, Russia, Serbia, Slovakia, Slovenia, Sweden, Switzerland Turkey and Ukraine Brown spruce longhorn beetle was found breeding in Rannoch Forest in

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

in 2015, the first record of this species in

Great Britain Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European ...

. The beetle was later identified at two other sites in Scotland, and there are also scattered reports from England. The collection of insects at the

Hunterian Museum The Hunterian is a complex of museums located in and operated by the University of Glasgow in Glasgow, Scotland. It is the oldest museum in Scotland. It covers the Hunterian Museum, the Hunterian Art Gallery, the Mackintosh House, the Zoology M ...

was reviewed, and a brown spruce longhorn beetle collected in Roslin in 1986 was discovered. Potentially brown spruce longhorn beetle may have been breeding in the UK for thirty years or more. Brown spruce longhorn beetle is an

invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

. It was first identified in 1999 in

Point Pleasant Park Point Pleasant Park is a large, mainly forested municipal park at the southern tip of the Halifax peninsula. It once hosted several artillery batteries, and still contains the Prince of Wales Tower - the oldest Martello tower in North America (1 ...

Halifax, Nova Scotia Halifax is the capital and most populous municipality of the Provinces and territories of Canada, Canadian province of Nova Scotia, and the most populous municipality in Atlantic Canada. As of 2024, it is estimated that the population of the H ...

. A review of specimens collected in the park in 1990 found that those labelled as the native species '' Tetropium cinnamopterum'' were ''Tetropium fuscum''. A single adult brown spruce longhorn was found in a trap in

Westmorland County, New Brunswick Westmorland County (2021 population: 163,576) is a county in New Brunswick, a province of Canada. It is in the south-eastern part of the province. It contains the fast-growing commercial centre of Moncton and its northern and eastern suburbs. ...

. Brown spruce longhorn beetle was probably introduced to Nova Scotia on wood

packaging material Packaging is the science, art and technology of enclosing or protecting products for distribution, storage, sale, and use. Packaging also refers to the process of designing, evaluating, and producing packages. Packaging can be described as a coo ...

imported into the

Port of Halifax The Port of Halifax comprises various port facilities in Halifax Harbour in Halifax, Nova Scotia, Canada. It covers of land, and looks after of water. Strategically located as North America's first inbound and last outbound gateway, the port of ...

Lifecycle

The

larvae A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect developmental biology, development such as insects, some arachnids, amphibians, or cnidarians typical ...

of brown spruce longhorn beetle are woodboring. Larvae of this beetle have been recorded infesting several different species of

including:

black spruce ''Picea mariana'', the black spruce, is a North American species of spruce tree in the pine family. It is widespread across Canada, found in all 10 provinces and all 3 territories. It is the official tree of Newfoundland and Labrador and is tha ...

blue spruce The blue spruce (''Picea pungens''), also commonly known as Colorado spruce or Colorado blue spruce, is a species of spruce tree native to North America in Arizona, Colorado, Idaho, New Mexico, Utah and Wyoming. It is noted for its blue-green co ...

Norway spruce ''Picea abies'', the Norway spruce or European spruce, is a species of spruce native to Northern, Central and Eastern Europe. It has branchlets that typically hang downwards, and the largest cones of any spruce, 9–17 cm long. It is very clo ...

red spruce ''Picea rubens'', commonly known as red spruce, is a species of spruce native to eastern North America, ranging from eastern Quebec and Nova Scotia, west to the Adirondack Mountains and south through New England along the Appalachians to wester ...

Sitka spruce ''Picea sitchensis'', the Sitka spruce, is a large, coniferous, evergreen tree growing to just over tall, with a trunk diameter at breast height that can exceed 5 m (16 ft). It is by far the largest species of spruce and the fifth- ...

and

white spruce White spruce is a common name for several species of spruce (''Picea'') and may refer to: * '' Picea engelmannii'', native to the Rocky Mountains and Cascade Mountains of the United States and Canada * ''Picea glauca ''Picea glauca'', the whi ...

as well as Scot's pine. Adult beetles emerge in the spring and summer months and will mate soon after emergence. The adult male beetles release an aggregation phremone called fuscumol, which will attract other brown spruce longhorn beetles to their location. After mating, females will select a suitable host tree for egg laying. Eggs may be laid on either standing trees or recently felled timber, with eggs laid on the bark. Larvae hatch out and bore into the

phloem Phloem (, ) is the living tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as ''photosynthates'', in particular the sugar sucrose, to the rest of the plant. This transport process is ...

of the wood where they will feed until they

pupate A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages the ...

the next spring and then emerge as adults.

Pest Status

In its European range, brown spruce longhorn beetle infests dead and dying trees, or recently felled timber. This infestation may occasionally lead to the death of diseased or stressed trees that may otherwise have recovered., and it is considered to sometimes be damaging to trees in Europe. In Canada, the pest initially appeared to be more aggressive and able to infest healthy

trees, with larval galleries girdling the stem and killing the tree. Though research showed that infested trees in Canada are of reduced vigour, and that larvae have a very low survival rate on healthy trees. Brown spruce longhorn may introduce

blue stain fungi Blue stain fungi (also known as sap stain fungi) is a vague term including various fungi that cause dark staining in sapwood. The staining is most often blue, but could also be grey or black. Because the grouping is based solely on symptomatics, i ...

when it infested trees or logs, which can reduce the value of timber.

References

External links

Tetropium fuscum
''BugwoodWiki''.
Species Profile: Brown Spruce Longhorned Beetle (''Tetropium fuscum'')
National Invasive Species Information Center,

United States National Agricultural Library The United States National Agricultural Library (NAL) is one of the world's largest agricultural research libraries, and serves as a national library of the United States and as the library of the United States Department of Agriculture. Locate ...

{{Taxonbar, from=Q901013 Spondylidinae Beetles described in 1787 Insect pests of temperate forests Beetles of Europe Beetles of Asia