Mussel of the

Page last updated
6 December 2023

Mussel of the Month

The December 2023 Mussel of the Month is Fusconaia cor. Fusconaia is a genus of 14 species from eastern North America.

Fusconaia cor
CM 61.6326. Clinch River, Speers Ferry, Scott Co., Virginia, USA
(type Fusconaia cor var. analoga Ortmann, 1918).

This month is the 50th anniversary of the Endangered Species Act in the U.S.A., so it is appropriate to focus on an endangered species that is benefiting from that historic legislation. Fusconaia cor, endemic to the Tennessee River basin in Alabama, Tennessee, and Virginia, is listed as endangered according to the U.S. Fish & Wildlife Service. It is listed as critically endangered on the IUCN Red List. A recent 5-year review nicely summarizes the current state of affairs for Fusconaia cor.

Another reason to highlight Fusconaia cor is to revisit taxonomy of the genus Fusconaia. The chart below summarizes the gist of the revisions to the classifications of the species traditionally assigned to Fusconaia. Our first checklist (Graf & Cummings, 2007) was based mostly on the late 20th century taxonomy since Burch (1975), and the then-current conception of Fusconaia was a mix of species that had previously been assigned to other genera like Pleuronaia, Elliptio, and Obovaria (Frierson, 1927; Haas, 1969). All of the red-bodied mussel species brooding their larvae in all four demibranchs were grouped in Fusconaia — or at least the mussels assumed to be red-bodied and tetragenous based on the similarity of their shells to mussels known to have those soft-body traits.

In the cladistic era, the traditional Fusconaia has acquired more species from now-defunct genera like Quincuncina and Lexingtonia, and other species have been exported to genera like Pleuronaia, Pleurobema, Pustulosa, and Reginaia (Campbell et al., 2005; Williams et al., 2008; Campbell & Lydeard, 2012). The latter two genera are classified in different tribes from each other and from Fusconaia! The available phylogenetic data are summarized on the Pleurobemini Cladomics page.

Things seems to have stabilized with Fusconaia — at least for the time being.


Phylum Mollusca
Class Bivalvia
Subclass Palaeoheterodonta
Order Unionoida

Superfamily UNIONOIDEA Rafinesque, 1820
Family UNIONIDAE s.s.
Subfamily AMBLEMINAE Rafinesque, 1820
Tribe PLEUROBEMINI Hannibal, 1912

Genus Fusconaia Simpson, 1900

Species Fusconaia cor (Conrad, 1834)

To find out more about the classification of Fusconaia and related genera, check out:

current tally

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