Hungerford's crawling water beetle
Encyclopedia
Hungerford's crawling water beetle (Brychius hungerfordi) is a critically endangered member of the Haliplidae family
of water beetle
s. The US Fish and Wildlife Service Draft Recovery Plan for the species published August 2004 estimates roughly 1000 individuals are present in the wild. In 2010, a five-year summary report by the US Fish and Wildlife Service found the population to be essentially unchanged.
The species was first discovered by Paul J. Spangler in 1954.
. The Hungerford's crawling water beetle is currently not protected in Canada
. At the time that the species was listed on the endangered species list, it was found only in three sites, all in Michigan. It is the most endangered species in Michigan and at the time of its listing, the only one limited exclusively to Michigan.
and one is in Ontario
.
. This location consists of a two and a half mile stretch of the river downstream from the Douglas Road crossing. This area supports the only stable population of the Hungerford's crawling water beetle, recording nearly 1052 beetles when last counted in 2002. This area is largely within and along the boundary of the University of Michigan Biological Station
.
Of the remaining sites, a second is also in Emmet County. This is near the Oliver Road crossing of the Carp Lake River
, where 4 adult specimens were recorded in 1997, but erosion at the road seems to have harmed the habitat and no specimens were found in the last survey conducted in
2003.
In Montmorency County, Michigan
two more sites have yielded official records of Hungerford's crawling water beetles. Along the East Branch of the Black River
inside the Mackinaw State Forest
, two adult beetles were found in surveys in 1989 and again in 1996 two more adults were found. Still, the status of the population there remains uncertain. In July 1999, six additional adult beetles were identified elsewhere in the Mackinaw State Forest in Van Hetton Creek.
The Carp Lake River and Van Hetton Creek identifications were significant as they represented a new location beyond those originally identified when the Hungerford's crawling water beetle was categorized as endangered in 1994. This suggests that the rare beetle may occur in other sites as yet undiscovered.
near Scone in Bruce County, Ontario
. In 1986, 42 beetles were identified at a site downstream from a dam there. An unspecified number of beetles were last recorded in 2001, but surveys in 2002 uncovered no specimens. As a result, the status of this population of Hungerford's crawling water beetles is uncertain at present.
dams.
of the Hungerford crawling water beetle is more or less ovoid, with a markedly convex upperside. They is have a yellowish-brown color with irregular dark markings. They are extremely small (3.8 millimetre long) which may contribute to the difficulty in locating them. Their wing covers
are characterized by perforated stripes. The sides of their pronotum
(dorsal plate behind the head) are nearly parallel for the basal two-thirds before widening at the sides.
As characteristic of all Haliplidae, the hindlegs of Hungerford crawling water beetles have a very distinctive and comparatively large coxal plates that cover most of the beetle's abdomenal underside as well as parts of its hindlegs. These hindleg plates do not move although they are not fused to the beetle's centerline. As with all Haliplidae, these specialized hindleg plates function as air storage devices supplementing the air carried under the wing covers.
Although most other Haliplidae are capable of flight, no observation has ever been recorded of a Hungerford crawling water beetle flying. The absence of flight may contribute to the extreme limitation of its habitat, as flight might have helped it to spread over a larger area.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
of water beetle
Water beetle
A water beetle is a beetle adapted to living in water. Water beetles rise to the water surface and take atmospheric air into their tracheal systems. There are approximately 2000 species of water beetles. The rest marine species tend to live in the intertidal zone...
s. The US Fish and Wildlife Service Draft Recovery Plan for the species published August 2004 estimates roughly 1000 individuals are present in the wild. In 2010, a five-year summary report by the US Fish and Wildlife Service found the population to be essentially unchanged.
The species was first discovered by Paul J. Spangler in 1954.
Endangered status
Hungerford's crawling water beetle was categorized as endangered on March 7, 1994, under the provisions of the U.S. Endangered Species ActEndangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
. The Hungerford's crawling water beetle is currently not protected in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. At the time that the species was listed on the endangered species list, it was found only in three sites, all in Michigan. It is the most endangered species in Michigan and at the time of its listing, the only one limited exclusively to Michigan.
Known populations
Known populations of Hungerford's crawling water beetles are limited to cold-water streams in only five locations. Four of these are in MichiganMichigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
and one is in Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
.
Michigan locations
Almost all known Hungerford's crawling water beetles live in a single location: the East Branch of the Maple River in Emmet County, MichiganEmmet County, Michigan
Emmet County is a county in the U.S. state of Michigan. As of the 2000 census, the population was 31,437. The county seat is Petoskey.The county was formed April 1, 1840, from Mackinac County. It was first named Tonedagana County and renamed Emmet County on March 8, 1843...
. This location consists of a two and a half mile stretch of the river downstream from the Douglas Road crossing. This area supports the only stable population of the Hungerford's crawling water beetle, recording nearly 1052 beetles when last counted in 2002. This area is largely within and along the boundary of the University of Michigan Biological Station
University of Michigan Biological Station
The University of Michigan Biological Station is a research and teaching facility operated by the University of Michigan. It is located on the south shore of Douglas Lake in Cheboygan County, Michigan. The station consists of 10,000 acres of land near Pellston, Michigan in the northern Lower...
.
Of the remaining sites, a second is also in Emmet County. This is near the Oliver Road crossing of the Carp Lake River
Carp Lake River
The Carp Lake River is a river in Emmet County, Michigan.The Carp Lake River is one of only five locations in the world where the critically endangered Hungerford's Crawling Water Beetle has been found...
, where 4 adult specimens were recorded in 1997, but erosion at the road seems to have harmed the habitat and no specimens were found in the last survey conducted in
2003.
In Montmorency County, Michigan
Montmorency County, Michigan
-Michigan State trunklines:* M-32* M-33-Michigan State trunkline business loops:* Business M-32 is short, disconnected route in the village of Hillman.-Montmorency County intercounty highways:* F-01* F-21-Demographics:...
two more sites have yielded official records of Hungerford's crawling water beetles. Along the East Branch of the Black River
Black River (Michigan)
Black River may refer to any of seven streams in the U.S. state of Michigan:* Black River , flows into Lake Huron at the community of Black River, Michigan...
inside the Mackinaw State Forest
Mackinaw State Forest
The Mackinaw State Forest is a forested area owned by the U.S. state of Michigan and operated by the Michigan Department of Natural Resources. It is located in the northern area of the Lower Peninsula within the eight counties of Alpena, Antrim, Charlevoix, Cheboygan, Emmet, Montmorency, Otsego,...
, two adult beetles were found in surveys in 1989 and again in 1996 two more adults were found. Still, the status of the population there remains uncertain. In July 1999, six additional adult beetles were identified elsewhere in the Mackinaw State Forest in Van Hetton Creek.
The Carp Lake River and Van Hetton Creek identifications were significant as they represented a new location beyond those originally identified when the Hungerford's crawling water beetle was categorized as endangered in 1994. This suggests that the rare beetle may occur in other sites as yet undiscovered.
Ontario location
The only known population of Hungerford's crawling water beetles outside of the United States inhabit the North Saugeen RiverSaugeen River
The Saugeen River is located in southern Ontario, Canada, flowing generally north-west about 160 km before exiting into Lake Huron. The river is navigable for some distance, and was once an important barge route...
near Scone in Bruce County, Ontario
Bruce County, Ontario
Bruce County is a county in western Ontario, Canada, and includes the Bruce Peninsula. As of 2006, the population was 65,349. The area was . The county seat is Walkerton, Ontario. It is located at ....
. In 1986, 42 beetles were identified at a site downstream from a dam there. An unspecified number of beetles were last recorded in 2001, but surveys in 2002 uncovered no specimens. As a result, the status of this population of Hungerford's crawling water beetles is uncertain at present.
Habitat
It is believed that the Hungerford's crawling water beetle requires cool (15–25 °C or 59–77 F), swift flowing alkaline streams with sand and gravel bottoms. While in their larval stage, the beetles gather in concentrations of microalgae and in slower moving waters. The beetles are thought to have historically favored beaverBeaver
The beaver is a primarily nocturnal, large, semi-aquatic rodent. Castor includes two extant species, North American Beaver and Eurasian Beaver . Beavers are known for building dams, canals, and lodges . They are the second-largest rodent in the world...
dams.
Description
Like all Haliplidae the imagoImago
In biology, the imago is the last stage of development of an insect, after the last ecdysis of an incomplete metamorphosis, or after emergence from the pupa where the metamorphosis is complete...
of the Hungerford crawling water beetle is more or less ovoid, with a markedly convex upperside. They is have a yellowish-brown color with irregular dark markings. They are extremely small (3.8 millimetre long) which may contribute to the difficulty in locating them. Their wing covers
Elytron
An elytron is a modified, hardened forewing of certain insect orders, notably beetles and a few of the true bugs ; in most true bugs, the forewings are instead called hemelytra, as only the basal half is thickened while the apex is membranous...
are characterized by perforated stripes. The sides of their pronotum
Prothorax
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites are the pronotum , the prosternum , and the propleuron on each side. The prothorax never bears wings in extant insects, though some fossil groups possessed...
(dorsal plate behind the head) are nearly parallel for the basal two-thirds before widening at the sides.
As characteristic of all Haliplidae, the hindlegs of Hungerford crawling water beetles have a very distinctive and comparatively large coxal plates that cover most of the beetle's abdomenal underside as well as parts of its hindlegs. These hindleg plates do not move although they are not fused to the beetle's centerline. As with all Haliplidae, these specialized hindleg plates function as air storage devices supplementing the air carried under the wing covers.
Although most other Haliplidae are capable of flight, no observation has ever been recorded of a Hungerford crawling water beetle flying. The absence of flight may contribute to the extreme limitation of its habitat, as flight might have helped it to spread over a larger area.