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Home/Species/ Cumberland Moccasinshell

Medionidus conradicus

(I. Lea, 1834)

Cumberland Moccasinshell

G3Vulnerable Found in 13 roadless areas NatureServe Explorer →
G3VulnerableGlobal Rank
Near threatenedIUCN
HighThreat Impact
Cumberland moccasinshell (Medionidus conradicus). Photo by U.S. Fish & Wildlife Service, Public Domain (U.S. Government Work), via ECOS.
U.S. Fish & Wildlife Service, https://www.usa.gov/government-works
Identity
Unique IDELEMENT_GLOBAL.2.110094
Element CodeIMBIV28020
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
IUCNNear threatened
Endemicendemic to a single nation
KingdomAnimalia
PhylumMollusca
ClassBivalvia
OrderUnionoida
FamilyUnionidae
GenusMedionidus
Concept Reference
Turgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2023-12-07
Change Date2023-12-07
Edition Date2023-12-07
Edition AuthorsCordeiro, J. (2009); rev. T. Cornelisse (2023)
Threat ImpactHigh
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences21 - 80
Rank Reasons
This species has a moderate range but due to long and short-term population declines and many ongoing threats, there are a limited number of viable occurrences.
Range Extent Comments
This species occurs in the Cumberland and Tennessee River Systems in eastern Kentucky, Virginia, Tennessee, Alabama, and Georgia, USA (USFWS 2020; GBIF 2023).
Occurrences Comments
This species is currently known from 34-63 watersheds, considered populations by the USFWS (USFWS 2020; USFWS 2023; GBIF 2023).
Threat Impact Comments
This species is threatened by sedimentation, nutrient, and chemical pollution from land conversion activities, including development, agriculture, oil and gas operations, and coal mining, dams and water diversions that change hydrologic conditions, host fish distribution, and prevent habitat connectivity and recolonization, and changes in precipitation (USFWS 2020; USFWS 2023).
Ecology & Habitat

Habitat

This species is found in riffles, runs, and shoals, and high gradient streams of small to medium-sized rivers with stable substrates of coarse sand, gravel, and/or cobble (USFWS 2020).

Reproduction

This species is a long-term brooder (USFWS 2020).
Other Nations (1)
United StatesN3
ProvinceRankNative
KentuckyS1Yes
TennesseeS3Yes
AlabamaS1Yes
VirginiaS3Yes
North CarolinaSXYes
GeorgiaS1Yes
Threat Assessments
ThreatScopeSeverityTiming
7 - Natural system modificationsLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
7.2 - Dams & water management/useLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
9 - PollutionLarge (31-70%)Serious or 31-70% pop. declineHigh (continuing)
9.2 - Industrial & military effluentsRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)
9.3 - Agricultural & forestry effluentsLarge - restrictedSerious - moderateHigh (continuing)
9.3.1 - Nutrient loadsLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
9.3.2 - Soil erosion, sedimentationLarge - restrictedSerious - moderateHigh (continuing)
11 - Climate change & severe weatherRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)
11.1 - Habitat shifting & alterationRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)

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Roadless Areas (13)
Idaho (1)
AreaForestAcres
Bear CreekCaribou-Targhee National Forest118,582
North Carolina (1)
AreaForestAcres
SnowbirdNantahala National Forest8,489
Tennessee (4)
AreaForestAcres
Bald River Gorge AdditionCherokee National Forest1,728
Brushy RidgeCherokee National Forest7,469
Sycamore CreekCherokee National Forest6,984
Upper Bald RiverCherokee National Forest9,202
Virginia (7)
AreaForestAcres
Bear CreekJefferson National Forest18,274
Beartown Addition AJefferson National Forest1,370
Beartown Addition BJefferson National Forest2,985
Garden MountainJefferson National Forest3,960
Hunting Camp Little Wolf CreekJefferson National Forest8,953
Raccoon BranchJefferson National Forest4,388
Seng MountainJefferson National Forest6,428
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