(DRAFT) - Taxonomy
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
TAXONOMY
NAME - MUSSEL, PEARLY, WHITE WARTYBACK
OTHER COMMON NAMES - MUSSEL, PEARLY, WHITE WARTYBACK;MUSSEL, PEARLY and WHITE WARTY-BACK; WHITE WARTY-BACK; WHITE WARTYBACK
ELEMENT CODE -
CATEGORY - Aquatic Molluscs
PHYLUM AND SUBPHYLUM - MOLLUSCA,
CLASS AND SUBCLASS - BIVALVIA,
ORDER AND SUBORDER - UNIONOIDA,
FAMILY AND SUBFAMILY - UNIONIDAE,
GENUS AND SUBGENUS - PLETHOBASUS,
SPECIES AND SSP - CICATRICOSUS,
SCIENTIFIC NAME - PLETHOBASUS CICATRICOSUS
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
White Wartyback Pearly Mussel
Plethobasus cicatricosus (Say, 1829)
KINGDOM: Animal GROUP: Clam
PHYLUM: Mollusca CLASS: Bivalvia
ORDER: Unionoida FAMILY: Unionidae
P. cicatricosus is a medium-sized species that inhabits large
rivers (01). Valves are thick and solid, with an outline that ranges
from subovate to subtriangular (02). Beaks are high and turned
anteriorly. The dorsal margin of the shell is nearly straight, and
the posterior and ventral margins are evenly rounded (02). The
posterior ridge is low, narrowly rounded, and ends bluntly at or below
the medial line (01). The valve surface is marked with irregular
growth lines and a row of knobs from behind the umbo diagonally across
to the ventral margin. Periostracum is a dull yellow-brown to
greenish-yellow with no rays. Beak cavity is shallow with deep
anterior muscle scars and shallow posterior scars (02). Nacre color
is white and iridescent posteriorly (03,04). No sexual dimorphism
occurs in this species.
This species is closely related to the more common P. cyphyus
and was probably confused with this species by early malacologists
Taxonomy - 1 (DRAFT) - Taxonomy
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
(05). The 2 species were synonymized in 1922 (06), but most authors
continue to recognize them as distinct species (02). A taxonomic
discussion of this species was presented in 1983 (02).
Detailed descriptions and photographs of this species are
included in previous publications (01,02,07,08).
Taxonomy - 2 (DRAFT) - Status
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
STATUS
Coded Status
Alabama; Federal Endangered
Alabama; Unofficially Listed
Kentucky; Federal Endangered
Kentucky; State Recognized
Tennessee; Federal Endangered
Tennessee; State Listed
West Virginia; Federal Endangered
E: Federal Endangered
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The white wartyback pearly mussel (Plethobasus cicatricosus) 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 States of Alabama, Illinois, Indiana, Kentucky,
Tennessee, and West Virginia. According to the recovery plan, this
species has historically occurred in AL, IL, IN, KY, TN, and WV.
However, it is listed in the Federal Register as only occurring in
AL and TN.
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
Status - 1 (DRAFT) - Status
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
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: Illinois and Kentucky
DESIGNATED STATUS: Recognized Endangered
ADMINISTRATIVE AGENCY: (IL) Department of Conservation;
(KY) Department of Fish and Wildlife
Resources.
STATE STATUTES: (IL) Endangered Species Act, 1972, IL Revised
Statutes, Chapter 8, Section 331-340;
(KY) Fish and Wildlife Codes, 150.183.
Importing, transporting or possessing endangered
species of wildlife.
STATE: Indiana and Tennessee
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: (IN) Department of Natural Resources;
(TN) Wildlife Resources Agency.
STATE STATUTES: (IN) IN Code, Non-game and Endangered Species
Act, Public Law 128;
(TN) TN Annotated Code, Chapter 9, Section
51-901 through 51-912, Proclamations 75-15,
76-4, and amendments.
STATE: Alabama
UNOFFICIAL LIST: Endangered, Bulletin No.2, Endangered and
Threatened Plants and Animals of Alabama,
Alabama Museum of Natural History.
STATE: West Virginia
DESIGNATED STATUS: None.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
CITES I
ECONOMIC STATUSES:
There are no known commercial values for this species, however,
its 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.
74/10/17:39 FR 37078/37079 - Notice of review
75/09/26:40 FR 44329/44333 - Proposed rule
76/06/14:41 FR 24062/24067 - Final rule
Status - 2 (DRAFT) - Status
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
76/06/16:41 FR 24367/24378 - Proposal - CITES I
77/02/22:42 FR 10484/10485 - Final - CITES I
81/02/27:46 FR 14652/14658 - Five year review
87/07/07:52 FR 25523/25528 - Notice of review
Status - 3 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
LAND USE -
Streams and Canals
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, upper perennial UB1
Riverine, upper perennial SB1
COMMENTS ON HABITAT ASSOCIATIONS -
P. cicatricosus is a species found in large rivers, and occurs
in shoals with sand and gravel substrates (01). Because it was not a
common species, no other data are available on specific environmental
requirements for the adults or any other life stage. This species
does not occur in the impounded sections of rivers where it once
resided.
The 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 a
population. Habitat requirements or associations for the juvenile
stage are unknown.
Habitat Associations - 1 (DRAFT) - Food Habits
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
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, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
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, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
LIFE HISTORY
FOOD HABITS:
There are no known interspecific differences in feeding among
freshwater mussels (09). The glochidia are probably 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
(14,15). No study of the food habits of P. cicatricosus has been
conducted; required/preferred foods are therefore unknown.
HOME RANGE/TERRITORY:
Non-territorial. The species is sedentary during its adult life
and generally occurs in rivers with others of its kind.
PERIODICITY:
No known periodicity.
MIGRATION PATTERNS:
Non-migratory.
COVER/SHELTER REQUIREMENTS:
This species occurs in large rivers with sand and gravel
substrate. No species-specific information on cover/shelter is
available in the literature.
REPRODUCTIVE SITE REQUIREMENTS:
P. cicatricosus is a flowing water species that occurs in sand
and gravel substrates of large rivers (01). Since this species is
assumed to be sedentary and movement is inconsequential, this is the
type of environment where all life history processes are carried out,
including reproduction.
REPRODUCTIVE CHARACTERISTICS:
The reproductive cycle of P. cicatricosus 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, spawning in spring
and releasing glochidia in summer (01,02,16). Glochidia are
probably hookless and similar to those of P. cyphyus (17,18). 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, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
No information exists on the population biology of this species.
The species is taken occasionally by commercial musselmen (01).
SPECIES INTERRELATIONSHIPS:
The required fish hosts for the parasitic glochidia of this
species are unknown (01).
OTHER LIFE HISTORY DESCRIPTORS:
Because all of the recently collected specimens of this species
are very old, there is no evidence that viable populations still
exist.
Life History - 2 (DRAFT) - Management Practices
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
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 Land Acquisition
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 Transplanting Wild Eggs/Wild Seeds
Beneficial Controlling/Restricting Noncommercial Harvest
Beneficial Regulating commercial harvest levels
Adverse Incidental Capturing/Killing
Existing Incidental Capturing/Killing
Adverse Inherent Reproductive Characteristics
Existing Inherent Reproductive Characteristics
Adverse Low Gene Pool
Existing Low Gene Pool
Adverse Underground Mines
Existing Underground Mines
Adverse Surface Mines
Existing Surface Mines
Adverse Siltation
Existing Siltation
Adverse Water Temperature Alteration
Existing Water Temperature Alteration
Adverse Dissolved Oxygen Reduction
Existing Dissolved Oxygen Reduction
Adverse Water Level Fluctuation
Existing Water Level Fluctuation
Adverse Reservoirs
Existing Reservoirs
Adverse Migration barriers
Existing Migration barriers
Adverse Dredging
Existing Dredging
Adverse Applying herbicides
Existing Applying herbicides
Adverse Applying pesticides
Existing Applying pesticides
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
Adverse Erosion
Existing Erosion
Adverse
Management Practices - 1 (DRAFT) - Management Practices
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
RESULT MANAGEMENT PRACTICE
Existing
COMMENTS ON MANAGEMENT PRACTICES -
The mussel fauna in most streams of the Tennessee River drainage
has been impacted by dam construction, channelization, siltation, and
water pollution, which directly affect all mussel species (01,09).
The change from lotic to lentic conditions because of dams has also
altered the species composition of the fish community, thus
jeopardizing the reproductive success of some mussel species by
eliminating required fish hosts. Although siltation has been
suggested as the most significant adverse effect of impoundments on
mussels (09), other detrimental factors include lowered water
temperatures, pH changes, oxygen depletion, and dewatering of mussel
beds below dams (09). Mussel deaths can occur in substrate on which
0.6-2.5 cm of silt has accumulated, resulting in interference with
feeding and suffocation (10). The siphoning period and metabolic rate
of mussels can also be affected by such contaminants as heavy metals
and agricultural chemicals (11).
Water pollution has probably contributed to the decline of this
species. Acid mine drainage in tributaries of the Cumberland River
has reduced the diverse mussel assemblage that once occurred there
(12). Numerous tributaries in the upper Tennessee River drainage were
polluted already by the twentieth century, and the mussel fauna was in
a decline at that time (13). Coal waste from mining activities in
both Tennessee and Cumberland River tributaries has contributed
additional particulate and chemical pollutants.
All of the factors mentioned above (impoundments, siltation,
mining, and water pollution) are still considered potential threats to
remaining populations of P. cicatricosus. Other factors that may also
be affecting this species include incidental taking by commercial
musselmen, invasion of the Asiatic clam (Corbicula fluminea) into the
Tennessee and Cumberland Rivers, and the smaller gene pool which may
be approaching the minimum population size needed for sufficient
genetic variation to respond to environmental changes.
Substantial mussel die-offs of unknown origin that have
occurred in the Tennessee River drainage since 1982 pose a direct
threat to the species' survival and could potentially result in
its extinction.
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1984. White Wartyback Pearly Mussel
Recovery Plan. U.S. Fish and Wildlife Service. Atlanta, GA. 43 pp.
Recovery actions for the white wartyback pearly mussel include:
(1) Continue to utilize existing legislation and regulations to
protect the species and its habitat.
(2) Conduct population and habitat surveys to determine the status
Management Practices - 2 (DRAFT) - Management Practices
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
and range of the species.
(3) Determine present and forseeable threats to the species and
strive to minimize and/or eliminate them. These negative impacts are
likely to include road construction, dredging, herbicide and
pesticide spraying, industrial development, chlorinated effluents, and
the use of farm fertilizers.
(4) Identify essential habitat in need of protection. Investigate
the use of Scenic River status, mussel sanctuaries, land acquisition,
and/or other means for the protection of this habitat and utilize
where feasible. Immediate protection of any P. cicatricosus
populations found is of highest priority.
(5) Determine the feasibility of introducing the species back into
its historic range and introduce where feasible. Determine the best
methods for establishing new populations (e.g., introduction of adult
mussels, juveniles, infected fish hosts, artificially cultured
individuals and/or other means.
(6) Control the illegal take of this species by commercial musselmen.
Except for enforcement of regulatins, there are no recovery
efforts underway for this species.
Management Practices - 3 (DRAFT) - References
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 U.S. Fish and Wildlife Service. 1984. Recovery Plan for the White
Warty-back Pearly Mussel Plethobasus cicatricosus (Say, 1829).
U.S. Fish and Wildlife Service, Atlanta, GA. 43 pp.
02 Bogan, A.E. and P.W. Parmalee. 1983. Tennessee's rare wildlife
volume II: the mollusks. Tenn. Wildl. Resour. Agency, Tenn. Dep.
Conserv., and Tenn. Heritage Prog., Univ. Tenn., Knoxville, TN.
123 pp.
03 Simpson, C.T. 1914. A Descriptive Catalogue of the Naiades, or
Pearly Freshwater Mussels. Bryant Walker, Detroit, MI. 1540 pp.
04 Parmalee, P.W. 1967. The freshwater mussels of Illinois. Ill.
St. Mus. Pop. Sci. Ser. 8:1-108.
05 Frierson, L.S. 1911. Remarks on Unio varicosus, cicatricosus, and
Unio compertus, new species. Nautilus 25:51-54.
06 Ortmann, A.E. and B. Walder. 1922. On the nomenclature of certain
North American naiades. Occas. Pap. Mus. Zool., Univ. Mich.
No.112. 75 pp.
07 Parker, W. and L. Dixon. 1980. Endangered and threatened wildlife
of Kentucky, North Carolina, South Carolina, and Tennessee. NC.
Agric. Ext. Serv. 116 pp.
08 Stansbery, D.H. 1971. Rare and endangered mollusks in eastern
United States. Pages 5-18. IN: S.E. Jorgenson and R.E. Sharp
(eds.), Proceedings of a symposium on rare and endangered mollusks
(naiads) of the U.S. Bur. Sport Fish. Wildl., U.S. Fish and
Wildlife Service, Twin Cities, MN.
09 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.
10 Ellis, M.M. 1931. Some factors affecting the replacement of the
commercial fresh-water mussels. U.S. Bur. Fish. Circ. No.7.
10 pp.
11 Salanki, J. 1979. Behavioural studies in mussels under changing
environmental conditions. Symp. Biol. Hung. 19:169-176.
12 Neel, J.K. and W.R. Allen. 1964. The mussel fauna of the upper
Cumberland Basin before its impoundment. Malacologia 1:417-459.
13 Ortmann, A.E. 1918. The nayades (freshwater mussels) of the upper
Tennessee drainage with notes on synonymy and distribution. Proc.
Am. Phil. Soc., Phila. 57:521-626.
14 Coker, R.E., A.F. Shira, H.W. Clark, and A.D. Howard. 1921.
Natural history and propagation of fresh-water mussels. Bull. U.S.
Bur. Fish. 37:77-181.
15 Churchill, E.P, Jr. and S.I. Lewis. 1924. Food and feeding in
freshwater mussels. Bull. U.S. Bur. Fish. 39:439-471.
16 Wilson, C.B. and H.W. Clark. 1914. The mussels of the Cumberland
River and its tributaries. U.S. Bur. Fish. Doc. No.781. 63 pp.
17 Ortmann, A.E. 1912. Notes upon the families and genera of the
nayades. Ann. Carnegie Mus. 8:222-365.
18 Ortmann, A.E. 1919. A monograph of the naiades of Pennsylvania
Part 3. Systematic account of the genera and species. Mem.
Carnegie Mus. 8:1-389.
References - 1 (DRAFT) - References
Species MUSSEL, PEARLY, WHITE WARTYBACK
Species Id ESIS404018
Date 13 MAR 96
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 U.S. Fish and Wildlife Service. 1984. Recovery Plan for the White
Warty-back Pearly Mussel Plethobasus cicatricosus (Say, 1829).
U.S. Fish and Wildlife Service, Atlanta, GA. 43 pp.
02 Stansbery, D.H. 1971. Rare and endangered mollusks in eastern
United States. Pages 5-18. IN: S.E. Jorgenson and R.E. Sharp
(eds.), Proceedings of a symposium on rare and endangered mollusks
(naiads) of the U.S. Bur. Sport Fish. Wildl., U.S. Fish and
Wildlife Service, Twin Cities, MN.
03 Stansbery, D.H. 1964. The Mussel (Muscle) Shoals of the Tennessee
River revisited. Annu. Rep. Am. Malacol. Union 1964:25-28.
04 Isom, B.G. 1969. The mussel resources of the Tennessee River.
Malacologia 7:397-425.
05 Stansbery, D.H. 1976. Naiad mollusks. Pages 42-52. IN:
Endangered and threatened plants and animals of Alabama. Ala. Mus.
Nat. Hist. Bull. No.2.
06 Johnson, R.I. 1980. Zoogeography of North American Unionacea
(Mollusca:Bivalvia) north of the maximum Pleistocene glaciation.
Mus. Comp. Zool. Bull. No.149. 189 pp.
07 Bogan, A.E. and P.W. Parmalee. 1983. Tennessee's rare wildlife
volume II: the mollusks. Tenn. Wildl. Resour. Agency, Tenn. Dep.
Conserv., and Tenn. Heritage Prog., Univ. Tenn., Knoxville, TN.
123 pp.
08 Lewis, J. 1871. On the shells of the Holston River. Am. J.
Conch. 6:216-228.
09 Goodrich, C. and H. van der Schalie. 1944. A revision of the
mollusca of Indiana. Am. Midl. Nat. 32:257-326.
10 Simpson, C.T. 1914. A Descriptive Catalogue of the Naiades, or
Pearly Freshwater Mussels. Bryant Walker, Detroit, MI. 1540 pp.
11 Stansbery, D.H. 1972. A preliminary list of the naiad shells
recovered from the Buffalo Site. Pages 105-106. IN: B.J.
Broyles, A late 17th century indian village site. (46 PU 31) in
Putnam County, West Virginia. Rep. Archaeol. Invest. No.5, WV.
Geol. Econ. Serv., Morgantown, WV.
References - 2