FWS Focus

Overview

Characteristics
Overview

The salamander mussel (Simpsonaias ambigua) is a species of freshwater mussel currently found in scattered populations across 14 states from New York southwest to Arkansas. The salamander mussel is a small, thin-shelled mussel that inhabits swift-flowing rivers and streams with areas of shelter under rocks or in crevices. The mussel is found in Arkansas, Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, Tennessee, West Virginia, Wisconsin and Ontario, Canada. The salamander mussel lives for approximately 10 years.

Scientific Name

Simpsonaias ambigua
Common Name
salamander mussel
FWS Category
Clams
Kingdom

Location in Taxonomic Tree

Identification Numbers

TSN:

Characteristics

Characteristic category

Life Cycle

Characteristics
Life Cycle

Similar to other freshwater mussels, the salamander mussel has a unique life cycle that relies on a host for successful reproduction, but the salamander mussel is the only freshwater mussel in North America to use a non-fish host. The mudpuppy (Necturus maculosus), the only known host for salamander mussel, is a fully aquatic salamander species that tends to be present within the same habitat preferred by the salamander mussel during the summer and fall when female mudpuppies are guarding their nests under large flat rocks. The salamander mussel’s larvae (called glochidia) develop on the gills of the mudpuppy before falling off into the stream substrate.   

Life Span

The salamander mussel lives for approximately 10 years.

Characteristic category

Habitat

Characteristics
Habitat

This mussel inhabits swift-flowing rivers and streams with areas of shelter under rocks or in crevices. 

River or Stream

A natural body of running water.

Characteristic category

Food

Characteristics
Food

Like other freshwater mussels, the salamander mussel feeds on particles, including phytoplankton, zooplankton, rotifers, protozoans, detritus, and dissolved organic matter, in sediments or suspended in the water. 

Characteristic category

Physical Characteristics

Characteristics
Size & Shape

The salamander mussel is a small, thin shelled species about 2 inches long.

Geography

Characteristics
Range

The salamander mussel is found across 14 U.S. States (Arkansas, Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, Tennessee, West Virginia, and Wisconsin) and Ontario, Canada.

Launch Interactive Map

Timeline

Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.

6 Items

Listing

Listing

Listing

Listing

Listing

Listing

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Listing

May 22, 1984

May 22, 1984 Listing
Review of Invertebrate Wildlife for Listing as Endangered or Threatened Species; 49 FR 21664-21675
  • Publication type: CNOR
Item 1

Listing

Jan 6, 1989

Jan 6, 1989 Listing
ETWP; Animal Notice of Review; 54 FR 554 579
  • Publication type: CNOR
Item 2

Listing

Nov 21, 1991

Nov 21, 1991 Listing
ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species; 56 FR 58804 58836
  • Publication type: CNOR
Item 3

Listing

Nov 15, 1994

Nov 15, 1994 Listing
ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species.
  • Publication type: CNOR
Item 4

Listing

Sep 27, 2011

Sep 27, 2011 Listing (Substantial)
Partial 90-Day Finding on a Petition To List 404 Species in the Southeastern United States as Endang…
  • Publication type: 90 day petition finding
Item 5

Listing

Aug 22, 2023

Aug 22, 2023 Listing (Warranted)
Endangered Species Status for Salamander Mussel and Designation of Critical Habitat
  • Publication type: 12m petition finding
Item 6