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Home/Species/ Littlewing Pearlymussel

Pegias fabula

(I. Lea, 1838)

Littlewing Pearlymussel

G1Critically Imperiled Found in 1 roadless area NatureServe Explorer →
G1Critically ImperiledGlobal Rank
Critically endangeredIUCN
Very high - highThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.116284
Element CodeIMBIV32010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
IUCNCritically endangered
Endemicendemic to a single nation
KingdomAnimalia
PhylumMollusca
ClassBivalvia
OrderUnionoida
FamilyUnionidae
GenusPegias
Other Common Names
Little Winged Pearly Mussel (EN)
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 Date2024-01-05
Change Date1997-10-01
Edition Date2024-01-05
Edition AuthorsShelton, D. N. (1997); rev. J. Cordeiro (2011); rev. T. Cornelisse (2024)
Threat ImpactVery high - high
Range Extent100-1000 square km (about 40-400 square miles)
Number of Occurrences1 - 5
Rank Reasons
This species has been extirpated from nearly all of its historically wide range, is subject to many ongoing threats, and likely has only one viable population.
Range Extent Comments
This species occurs in the Big South Fork Cumberland River in Kentucky and Tennessee, USA and in Cane Creek in Tennessee (USFWS 2020).
Occurrences Comments
This species is known from two extant occurrences (USFWS 2020).
Threat Impact Comments
This species is threatened by chemical pollution from energy operations and mining, dams and water diversions that change hydrological conditions and prevent habitat connectivity and recolonization, and habitat alteration due to climate change, including increased water temperatures and drought (USFWS 2020).
Ecology & Habitat

Habitat

This species is found in small to medium streams in riffles with sand and gravel substrates and moderate to high gradients (Bogan and Parmalee 1983; USFWS 2020).

Reproduction

This species is a long-term brooder and females are gravid from September until the following spring or summer (USFWS 2020).
Other Nations (1)
United StatesN1
ProvinceRankNative
North CarolinaS1Yes
TennesseeS1Yes
AlabamaSXYes
VirginiaS1Yes
KentuckyS1Yes
Threat Assessments
ThreatScopeSeverityTiming
7 - Natural system modificationsLarge (31-70%)Serious or 31-70% pop. declineHigh (continuing)
7.2 - Dams & water management/useLarge (31-70%)Serious or 31-70% pop. declineHigh (continuing)
9 - PollutionLarge - restrictedSerious - moderateHigh (continuing)
9.2 - Industrial & military effluentsLarge - restrictedSerious - moderateHigh (continuing)
11 - Climate change & severe weatherLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
11.1 - Habitat shifting & alterationLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)

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Roadless Areas (1)
Idaho (1)
AreaForestAcres
Bear CreekCaribou-Targhee National Forest118,582
References (41)
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