(DRAFT) - Taxonomy
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
TAXONOMY
NAME - MUSSEL, SPINY, TAR RIVER
OTHER COMMON NAMES - MUSSEL, SPINY, TAR RIVER; NAIAD and SPINY
ELEMENT CODE -
CATEGORY - Aquatic Molluscs
PHYLUM AND SUBPHYLUM - MOLLUSCA,
CLASS AND SUBCLASS - BIVALVIA,
ORDER AND SUBORDER - UNIONOIDA,
FAMILY AND SUBFAMILY - UNIONIDAE,
GENUS AND SUBGENUS - ELLIPTIO,
SPECIES AND SSP - STEINSTANSANA,
SCIENTIFIC NAME - ELLIPTIO STEINSTANSANA
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Tar River Spiny Mussel
Elliptio (Canthyria) steinstansana Johnson and Clarke, 1983
KINGDOM: Animal GROUP: Clam
PHYLUM: Mollusca CLASS: Bivalvia
ORDER: Unionoida FAMILY: Unionidae
This is a medium-sized species reaching 60 mm in length (01).
Valves are subinflated and inequilateral, with a rounded anterior end
and a blunt point on the posterior end below the medial line (01).
The ventral margin is slightly curved; the hinge ligament is prominent
but short. Umbos are slightly above the hinge line, in the anterior
third of the shell (01). Periostracum is generally smooth and shiny
with concentric growth lines. Valves usually contain one to several
short spines, perpendicular to the shell surface. Shell surface is
brown with variable greenish rays when young, becoming blackish-brown
with inconspicuous rays when old (01). Beak cavity is rather shallow;
nacre is yellow or pink anteriorly and bluish white and iridescent
posteriorly (01).
This relatively new species was described in 1983, with the
holotype taken from the Tar River in 1982 (01). E. steinstansana was
described by Johnson and Clarke and named for Carol Stein and David
Taxonomy - 1 (DRAFT) - Taxonomy
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
Stansbery.
There are presently 3 recognized species of spiny mussels in the
subgenus Canthyria; spinosa, collina, and steinstansana, each endemic
to the Altamaha, James, and Tar Rivers, respectively (02). A race of
spinose mussels may have existed in south Atlantic rivers millenia
ago, survived today by these 3 species (02). Until formally described
in 1983, E. (C.) steinstansana was referred to as Canthyria sp. (02),
Canthyria morrisoni (an invalid name used in an unpublished
manuscript, 03), and Pleurobema collina (04). A detailed description
of this species with photographs is available (01).
Taxonomy - 2 (DRAFT) - Status
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
STATUS
Coded Status
North Carolina; Federal Endangered
North Carolina; State Recognized
North Carolina; Unofficially Listed
E: Federal Endangered
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Tar River spiny mussel, Elliptio (Canthyria) steinstansana,
has been designated an Endangered species pursuant to the Endangered
Species Act of 1973 (50 CFR 17.11; P.L. 93-205, 87 Stat. 884; 16
U.S.C. 1531-1540), as amended. The species has this status wherever
found including the State of North Carolina.
This species is protected by the Lacey Act (P.L. 97-79, as
amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import,
export, transport, sell, receive, acquire, or purchase any wild animal
(alive or dead including parts, products, eggs, or offspring):
(1) in interstate or foreign commerce if taken, possessed,
transported or sold in violation of any State law or
regulation; or
(2) if taken or possessed in violation of any U.S. law,
treaty, or regulation or in violation of Indian tribal law.
It is also unlawful to possess any wild animal (alive or dead
including parts, products, eggs, and offspring) within the U.S.
territorial or special maritime jurisdiction (as defined in
18 U.S.C. 7) that is taken, possessed, transported, or sold in
violation of any State law or regulation, foreign law, or Indian
tribal law.
RESPONSIBLE FEDERAL AGENCIES:
USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
DOD (COE) -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control. Also responsible for
management/recovery on Department of Defense lands.
All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species or result in the
destruction or adverse modification of Critical Habitat (50 CFR 402),
and to utilize their authorities to carry out programs for the
conservation of the species.
STATE STATUSES AND LAWS:
STATE: North Carolina
DESIGNATED STATUS: Recognized Endangered
Status - 1 (DRAFT) - Status
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
ADMINISTRATIVE AGENCY: Wildlife Commission
STATE STATUTE: State Law, Subsection 113.272.4, prohibits the
collection of wildlife, including freshwater
mussels, without a permit.
UNOFFICIAL LIST: High Priority, list compiled by a study group
of experts for the NC Wildlife Commission in
the late 1970's, listed under the name
Canthyria sp.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
None.
ECONOMIC STATUSES:
No commercial values are known, however, the species' sedentary
nature and filter feeding habits may make it useful as a water quality
indicator. It has been shown that mussels accumulate such pollutants
as heavy metals and pesticides.
82/03/05:47 FR 09483/09485 - Notice of review
84/05/22:49 FR 21664/ - Invertebrate candidate list
84/09/17:49 FR 36418/36420 - Proposed rule
85/06/27:50 FR 26572/26575 - Final rule
Status - 2 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
LAND USE -
Streams and Canals
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, upper perennial UB2
Riverine, upper perennial SB3
Riverine, upper perennial SB2
COMMENTS ON HABITAT ASSOCIATIONS -
This shallow water species has been reported from sand and mud
substrates in the Tar River. Its presence in muskrat middens suggest
that it also occurs in deeper water (02). During the 1982 survey,
this species was collected at sites with the following characteristics
(05): water depth, 0.1-0.3 m; maximum current speed, 0.26-0.50 m/s;
and principally sand substrate. During FY75, USGS data for the Tar
River at Tarboro was as follows: temperature, 5.0-27.0 degrees C;
discharge,27-2190 cubic feet per second (06). Total hardness of water
apparently fluctuates greatly with changing water levels in the Tar
River (05).
Specific environmental requirements for adults or other life
stages are unknown. Habitat of the glochidia is initially within the
gills of the female, then in the water column, and finally attached to
a suitable fish host. Any alteration of these life stage-specific
habitats during its life cycle would likely affect the long-term
success of the population.
Habitat Associations - 1 (DRAFT) - Food Habits
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
FOOD HABITS
TROPHIC LEVEL -
OMNIVORE
LIFESTAGE FOOD FOOD PART
General Detritus
General Bacteria
General Phytoplankton
General Diatoms
General Zooplankton
General Fish
Food Habits - 1 (DRAFT) - Environment Associations
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Aquatic Features: Pool areas
Environment Associations - 1 (DRAFT) - Life History
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
LIFE HISTORY
FOOD HABITS:
There are no known interspecific differences in feeding among
freshwater mussels (07). The glochidia are obligate parasites on the
gills or fins of fish. Adult mussels are filter-feeders and consume
particulate matter suspended in the water column. Identifiable
stomach contents almost invariably include mud, desmids, diatoms,
other unicellular algae, protozoa, and zooplankters (08,09). No study
of the food habits of E. steinstansana has been conducted;
required/preferred foods are therefore unknown.
HOME RANGE/TERRITORY:
Non-territorial. The species is apparently sedentary under
stable water conditions during its adult life, and it occurs with
others of its kind in the Tar River.
PERIODICITY:
No known periodicity.
MIGRATION PATTERNS:
Non-migratory. Movement will occur if water levels recede to
expose specimens.
COVER/SHELTER REQUIREMENTS:
This species occurs in the sand and mud substrates of the Tar
River. No species-specific information on cover/shelter is available
in the literature.
REPRODUCTIVE SITE REQUIREMENTS:
The Tar River spiny mussel is a flowing water species that occurs
in sand and mud substrates (05). Since the species is relatively
sedentary, this is the type of environment where all life history
processes are carried out, including reproduction.
REPRODUCTIVE CHARACTERISTICS:
The reproductive cycle of E. steinstansana is presumed to be
similar to other freshwater mussels. During spawning, males discharge
sperm into the water column, and the sperm are taken in by the females
during siphoning. eggs are fertilized in the female's suprabranchial
cavity or gills, which serve as marsupia for embryos developing to the
parasitic stage (glochidia). Glochidia are released by the female and
must attach to a suitable fish host for metamorphosis to the
free-living juvenile stage.
This species is probably a short-term breeder like other Elliptio
spp., spawning in spring and releasing glochidia in early summer.
Fish hosts are unknown.
PARENTAL CARE:
Except for retention of the glochidia within the gills of the
female prior to release, no parental care occurs.
POPULATION BIOLOGY:
Life History - 1 (DRAFT) - Life History
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
No information exists on the population biology of this species.
Some evidence exists which indicates declines in population size and
habitat (05). Since 1977, 6 adults and 6 juveniles have been
collected in Edgecombe County (05). A population estimate of between
100 and 500 individuals was postulated in 1983 (05).
SPECIES INTERRELATIONSHIPS:
The required fish hosts for the parasitic glochidia of this
species are unknown (05). Other unionids collected in proximity to
E. (C.) steinstansana in the Tar River included E. complanata and
Lampsilis ochracea (05).
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 2 (DRAFT) - Management Practices
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Developing/maintaining stream structures
Beneficial Maintaining/Controlling Water Flow
Beneficial Controlling/Restricting Road Maintainance Actions
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Controlling pollution [thermal, chemical, physical]
Beneficial Controlling/Restricting Pesticide Use
Beneficial Controlling/Restricting Herbicide Use
Beneficial Controlling/Restricting Agricultural Practice
Beneficial Stocking captive-reared wild-strain animals
Beneficial Transplanting wild animals
Beneficial Restricting Poaching
Adverse Collecting
Existing Collecting
Adverse Inherent Reproductive Characteristics
Existing Inherent Reproductive Characteristics
Adverse Low Gene Pool
Existing Low Gene Pool
Adverse Siltation
Existing Siltation
Adverse Water Level Fluctuation
Existing Water Level Fluctuation
Adverse Irrigating
Existing Irrigating
Adverse Migration barriers
Existing Migration barriers
Adverse Dredging
Existing Dredging
Adverse Applying fertilizers
Existing Applying fertilizers
Adverse Applying herbicides
Existing Applying herbicides
Adverse Applying pesticides
Existing Applying pesticides
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Competition
Existing Competition
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
Adverse Erosion
Existing Erosion
Adverse
Existing
COMMENTS ON MANAGEMENT PRACTICES -
Because this species was described only recently, past reasons
for the current status are difficult to document. The Tar River has
above average loadings of nutrients and pesticides, and these
Management Practices - 1 (DRAFT) - Management Practices
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
pollutants probably affected the spiny mussel (05). Its absence below
Rocky Mount indicates that it may be sensitive to municipal sewage
(05).
Habitat loss has occurred in the Tar River since 1967. A dam and
reservoir above Rocky Mount in 1972 and the relocation of U.S. Highway
64 in 1977 (05), along with permanent and temporary dams, altered
habitat and probably caused the loss of this species in those areas
(05).
Invasion of the Asiatic clam (Corbicula fluminea) into the Tar
River recently may be affecting the success of the endemic mussel
fauna. Possible competition for food and space may result in higher
mortality for both juveniles and adults. Corbicula may also interfere
with reproduction by filtering mussel sperm from the water column
(05).
North Carolina law prohibits collecting wildlife, including
mussels, without a permit. However, shell collectors and unscrupulous
malacologists may seek to collect specimens.
Due primarily to pollution and habitat loss, it is estimated that
this species has decreased its range by 50% since 1966 (05).
Future threats include those previously mentioned as well as a
proposed hydropower project at an upstream dam in Rocky Mount.
Fluctuating water levels and changes in water quality could affect the
downstream population. Similarly, the withdrawal of large volumes of
water from the river during drought conditions could expose habitat
typically used by this species. In addition the small gene pool that
presently exists may be approaching the minimum population size needed
for sufficient genetic variation to respond to environmental changes.
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1987. Recovery Plan for the Tar
River Spiny Mussel (Elliptio (Canthyria) steinstansana) Johnson and
Clarke. U.S. Fish and Wildlife Service, Atlanta, GA. 23 pp.
Management actions recommended for the recovery of the Tar River
spiny mussel include:
(1) Monitor the known population and identify threats to that
population. Based on known habitat requirements of this species and
known negative impacts to other freshwater mussels, negative impacts
probably include herbicide and pesticide use, water pollutants, poor
agricultural practices, development, road maintenance, and
impoundments. Habitat restoration or improvement may be necessary to
improve conditions for survival of the species (i.e., restoration of
stream banks and channels and assuring optimum clean water flow).
(2) Seek support for mitigation of threats to and protection of the
species. Educate the public, particularly landowners along the river
locations where this species occurs, to define their roles in
protection of endangered species and to gain support for habitat
protection.
(3) Research to determine the species' current distribution and
Management Practices - 2 (DRAFT) - Management Practices
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
range, habitat requirements, life history, and population biology.
(4) Develop techniques for reintroducing the species back into its
historic range. Artificial rearing and maintenance of individuals for
subsequent release may expedite recovery of the species.
(5) Periodically monitor existing populations and all introduced
populations in the Tar River.
Management Practices - 3 (DRAFT) - References
Species MUSSEL, SPINY, TAR RIVER
Species Id ESIS404010
Date 13 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Johnson, R.I. and A.H. Clarke. 1983. A new spiny mussel, Elliptio
(Canthyria) steinstansana (Bivalvia:Unionidae) from the Tar River,
North Carolina. Mus. Comp. Zool. Occas. Pap. Mollusks
4(61):289-298.
02 Fuller, S.L.H. 1977. Freshwater and terrestrial mollusks. Pages
143-194. IN: J.E. Cooper, S.S. Robinson, and J.B. Funderburg
(eds.). Endangered and threatened plants and animals of North
Carolina. N.C. State Mus. Nat. Hist., Raleigh, NC.
03 Clarke, A.H. 1978. Unpublished manuscript. Canthyria morrisoni
(new species) (Unionidae) and other mollusks from a unique
ecosystem: the Tar River, North Carolina. 27 pp.
04 Johnson, R.I. 1970. The systematics and zoogeography of the
Unionidae (Mollusca:Bivalvia) of the southern Atlantic Slope
region. Bull. Mus. Comp. Zool. 140:263-449.
05 Clarke, A.H. 1983. Status survey of the Tar River spiny mussel.
Final Rep., U.S. Fish and Wildlife Service, Asheville, NC. 51 pp.
06 Briggs, J.C. and J.F. Ficke. 1977. Quality of rivers of the
United States. U.S. Geological Survey, Open File Rep. 78-200.
07 Fuller, S.L.H. 1974. Clams and mussels (Mollusca:Bivalvia).
Pages 215-273. IN: C.W. Hart and S.L.H. Fuller (eds.). Pollution
Ecology of Freshwater Invertebrates. Academic Press, NY.
08 Coker, R.E., A.F. Shira, A.W. Clarke, and A.D. Howard. 1921.
Natural history and propagation of fresh-water mussels. Bull. U.S.
Bur. Fish. 37:77-181.
09 Churchill, E.P., Jr. and S.I. Lewis. 1924. Food and feeding in
freshwater mussels. Bull. U.S. Bur. Fish. 39:439-471.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Clarke, A.H. 1983. Status survey of the Tar River spiny mussel.
Final Rep., U.S. Fish and Wildlife Service, Asheville, NC. 51 pp.
02 Shelley, R.M. 1972. In defense of mollusks. Wildl. in N.C.
36:4-8, 26-27.
03 Morrison, J.P.E. 1955. Notes on the spiny freshwater mussels
(Canthria). Bull. Am. Malacol. Union 1955:19-20.
04 Johnson, R.I. and A.H. Clarke. 1983. A new spiny mussel, Elliptio
(Canthyria) steinstansana (Bivalvia:Unionidae), from the Tar River,
North Carolina. Mus. Comp. Zool., Occas. Pap. Mollusks
4(61):289-298.
References - 1