Illinois Mussels

              This poster was made possible by:
Illinois Department of
Natural Resources
Division of Education
Illinois State Museum
Illinois Department
of Transportation
Text: Robert E. Warren, Illinois State Museum
Kevin S. Cummings, Illinois Natural History Survey
Design: Illinois State Museum
North America’s tremendous richness of pearly freshwater mussels is unique.
Biologists have identified nearly 300 species of mussels living in our streams
and lakes. Freshwater mussels are bivalved mollusks with two hard outer shells
and soft tissues inside. Prehistoric American Indians ate the soft tissues and used
the lustrous shells for making tools and ornaments. Historically, the shells have
been prized as raw material for manufacturing buttons and are currently used in
the production of cultured pearls.
Many mussels are sensitive to changes in their environment. Populations of mus-sels
have declined alarmingly in recent decades because of siltation, pollution, and
competition from exotic mollusks like the zebra mussel. Of the 80 mussel species
native to Illinois, more than half are currently threatened, endangered, extirpat-ed,
or extinct. We can protect mussels and other aquatic wildlife by cleaning up
our streams and lakes to create healthy habitats where these animals can thrive.
THREATENED/ENDANGERED SPECIES
16. Cyclonaias tuberculata, purple wartyback
17. Cyprogenia stegaria, fanshell
18. Ellipsaria lineolata, butterfly
19. Elliptio dilatata, spike
20. Epioblasma triquetra, snuffbox
21. Lampsilis fasciola, wavy-rayed lampmussel
22. Plethobasus cyphyus, sheepnose
23. Pleurobema clava, clubshell
24. Ptychobranchus fasciolaris, kidneyshell
25. Quadrula cylindrica, rabbitsfoot
26. Villosa iris, rainbow
EXTINCT SPECIES
27. Epioblasma flexuosa, leafshell
28. Epioblasma personata, round combshell
29. Epioblasma propinqua,Tennessee riffleshell
30. Epioblasma torulosa, tubercled blossom
INTRODUCED* SPECIES
31. Dreissena polymorpha, zebra mussels (attached
to Potamilus alatus, pink heelsplitter)
32. Corbicula fluminea,Asian clam
*See glossary.
COMMERCIAL SPECIES
1. Amblema plicata, threeridge
2. Fusconaia flava,Wabash pigtoe
3. Megalonaias nervosa, washboard
4. Quadrula quadrula, mapleleaf
COMMON SPECIES
5. Lampsilis cardium, plain pocketbook
6. Obliquaria reflexa, threehorn wartyback
7. Quadrula pustulosa, pimpleback
8. Truncilla donaciformis, fawnsfoot
9. Truncilla truncata, deertoe
10. Utterbackia imbecillis, paper pondshell
UNCOMMON/RARE SPECIES
11. Alasmidonta marginata, elktoe
12. Lampsilis teres, yellow sandshell
13. Quadrula metanevra, monkeyface
14. Tritogonia verrucosa, pistolgrip
15. Venustaconcha ellipsiformis, ellipse
1 2 3
4 5 6
8
7
9 10
16
13
14
15 17 18
20
21
27
28 29
30 31 32
22
25
11 12
23
24 26
19
Numbered profile drawings, grouped as
specimens are shown above, correspond to
numbered species names.Mussels are not shown
in equal proportion to actual size. Photographs
by Kevin S. Cummings; except Ptychobranchus
fasciolaris by Robert E.Warren.
Key
I l l i n o i s
MUSSELS