Monochamus maculosus

Haldeman, 1847

spotted pine sawyer

Monochamus maculosus, the spotted pine sawyer, is a longhorned beetle native to North America. It was formerly known as Monochamus mutator. are attracted to monochamol, a sex- produced by males. The breeds in stressed or recently dead conifers, with larvae tunneling in phloem and sapwood. It is a primary of the pinewood , the causal agent of .

Monochamus maculosus by (c) Claire Moxon-Waltz, some rights reserved (CC BY), uploaded by Claire Moxon-Waltz. Used under a CC-BY license.

1916. Monochamus maculosus wood borer larvae in galleries in pine wood. (38189917322) by R6, State & Private Forestry, Forest Health Protection. Used under a Public domain license.

Pronunciation

How to pronounce Monochamus maculosus: /mɒˈnɒkəməs ˌmækjʊˈloʊsəs/

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

Images

Habitat

Mixed wood forest stands, primarily in clear-cut areas. In the Great Lakes-St. Lawrence Forest Region of Ontario, Canada, found in stands dominated by Pinus banksiana (ca. 80%) with associated Pinus strobus, P. resinosa, Populus grandidentata, Betula alleghaniensis, Ostrya virginiana, Acer saccharum, and Acer rubrum. Occupies both down and standing dead trees with vertical distribution across the forest .

Distribution

Canada (Ontario, specifically Algoma District and Great Lakes-St. Lawrence Forest Region) and the United States (northeastern). Formerly known as Monochamus mutator.

Seasonality

activity occurs later in the season compared to sympatric Monochamus scutellatus. No diel rhythm in production has been demonstrated.

Diet

feed on foliage of Pinus resinosa. Larvae feed in phloem and excavate U-shaped galleries into sapwood of trees.

Host Associations

Pinus banksiana - preferred in field attraction experiments
Pinus strobus - associated in
Pinus resinosa - foliage feeding documented
Picea - attacked when severely stressed or recently dead
Abies - attacked when severely stressed or recently dead
Populus grandidentata - associatedpresent in
Betula alleghaniensis - associatedpresent in
Ostrya virginiana - associatedpresent in
Acer saccharum - associatedpresent in
Acer rubrum - associatedpresent in

Life Cycle

Females lay in phloem of trees through crevices or oviposition slits in bark. Larvae feed in phloem, then excavate deep U-shaped galleries into sapwood for . The complete duration has not been documented for this specifically.

Behavior

Males produce monochamol (2-(undecyloxy)ethanol), an - that attracts both sexes. Greater attraction to monochamol combined with jack pine foliage than with balsam fir or white spruce. activity occurs later in the season and day compared to M. scutellatus, which may contribute to partial reproductive isolation. No qualitative differences in components with sympatric M. scutellatus. Vertical abundance similar to M. scutellatus across forests.

Ecological Role

Secondary pest: larval tunneling downgrades wood value. Primary of pinewood Bursaphelenchus xylophilus, the causal agent of . Contributes to decomposition of stressed and dead conifers in forest .

Human Relevance

Economic pest due to wood degradation from larval tunneling. Significant forest health concern as the primary of pinewood , which causes . Formerly known as Monochamus mutator, which may appear in older literature.

Similar Taxa

Monochamus scutellatusSympatric in Ontario; shares monochamol with no qualitative differences in components; distinguished by earlier seasonal activity and earlier daily flight times
Monochamus notatusSympatric in Ontario; shares monochamol ; similar vertical abundance and spatial distribution within
Monochamus clamatorAnother spotted pine sawyer with similar ; M. maculosus specifically associated with jack pine preference in field studies

More Details

Reproductive isolation mechanisms

No evidence that or preferences contribute to reproductive isolation among sympatric Monochamus . Minor temporal differences in times (seasonal and daily) may contribute to partial reproductive isolation between M. maculosus and M. scutellatus.

Pheromone characteristics

M. maculosus produces monochamol as an -. No diel rhythm in production has been detected in M. scutellatus, and this has not been directly tested for M. maculosus due to low lab colony numbers.

Taxonomic history

Formerly known as Monochamus mutator. The name change may cause confusion in older literature and collections.