Mussel of the

Page last updated
6 March 2019

Mussel of the Month

The March 2019 Mussel of the Month is Utterbackia peggyae. Utterbackia is a genus of three species from eastern North America.

MCZ 251040. SE shore of Lake Talquin at Leon Co., public fishing ground, Leon Co., Florida(type).

Utterbackia imbecillis was the Mussel of the Month almost five years ago. There are still lots of genera we haven’t even gotten to yet, but we wanted to honor our friend Richard Johnson this month with a freshwater mussel that he named, so we chose U. peggyae. Richard has a birthday coming up, and we were recently reminded that he is probably the longest surviving member of the American Malacological Society/Union (Mikkelsen, 2010). Richard Johnson attended his first AMU meeting in his teens before World War II (Boss, 1998)!

During Richard Johnson’s career in the Mollusk Department at Harvard’s Museum of Comparative Zoology, he contributed to our knowledge of freshwater mussel systematics in important and lasting ways. He published type catalogues for many of the most important collections (e.g., Lamarck, Lea, MCZ, UMMZ, ANSP) and biographies of significant malacologists (e.g., Ortmann, Frierson, Call). He took on Elliptio and other genera on the Atlantic Slope, post-Pleistocene biogeography (Johnson, 1980), and a revision of Epioblasma. Richard also described new species, and he did so with memorable flair. There are the three he named for the women in his life, Haasodonta fannyae, Utterbackia peggyae, and Margaritifera marrianae. That is probably the most romantic thing we have ever heard of. He also named three more by mildly Latinizing concatenations of the names of his contemporary unio aficionados. Samuel L.H. Fuller, Pieter W. Kat, Carol B. Stein, David H. Stansbery, Artie L. Metcalf, Raymond W. Neck, and Dwight W. Taylor have been immortalized as Lampsilis fullerkati, Parvaspina steinstansana, and Potamilus metnecktayi. It should be remembered that much of this work was done before freshwater mussels attracted the attention they do today. Back in the day, Unionidae was just another obscure family of bivalves.

We also know Richard Johnson as a generous friend and mentor, serving on DLG’s M.Sc. thesis committee. Thank you, Mr. Johnson, for your contributions to freshwater malacology!


Phylum Mollusca
Class Bivalvia
Subclass Palaeoheterodonta
Order Unionoida

Superfamily UNIONOIDEA Rafinesque, 1820
Family UNIONIDAE s.s
Subfamily UNIONINAE s.s.
Tribe ANODONTINI Rafinesque, 1820

Genus Utterbackia F.C. Baker, 1927

Species Utterbackia peggyae (R.I. Johnson, 1965)

To find out more about Richard Johnson and his contributions to freshwater mussel taxonomy, check out:
  • Boss, K.J. 1998. Richard Irwin Johnson. Occasional Papers on Mollusks 5: iii-ix.
  • Mikkelsen, P.M. 2010. Seventy-five years of molluscs: A history of the American Malacological Society on the occasion of its 75th annual meeting. American Malacological Bulletin 28: 191-213.
  • Johnson, R.I. 1952-1953. A study of Lamarck's types of Unionidae and Mutelidae. Nautilus 66: 63-67, 90-95.
  • Johnson, R.I. 1956. The types of naiades (Mollusca: Unionidae) in the Museum of Comparative Zoology. Bulletin of the Museum of Comparative Zoology 115(4): 101-142.
  • Johnson, R.I. 1969. Illustrations of Lamarck's types of North American Unionidae mostly in the Paris Museum. Nautilus 8: 52-61.
  • Johnson, R.I. 1970. The systematics and zoogeography of the Unionidae (Mollusca: Bivalvia) of the southern Atlantic Slope Region. Bulletin of the Museum of Comparative Zoology 140(6): 263-449.
  • Johnson, R.I. 1972. Illustrations of all of the mollusks described by Lorraine Screven Frierson. Occasional Papers on Mollusks 3(41): 137-173.
  • Johnson, R.I. & H.B. Baker. 1973. The types of Unionacea (Mollusca: Bivalvia) in the Academy of Natural Sciences of Philadelphia. Proceedings of the Academy of Natural Sciences of Philadelphia 125: 145-186.
  • Johnson, R.I. 1974. Lea's unionid types or recent and fossil taxa of Unionacea and Mutelacea introduced by Isaac Lea, including the location of all the extant types. Special Occasional Publications of the MCZ (2): 159 pp.
  • Johnson, R.I. 1975. Ellsworth Call with a bibliography of his works on mollusks and a catalogue of his taxa. Occasional Papers on Mollusks 4(54): 133-144.
  • Johnson, R.I. 1977. Arnold Edward Ortmann, a bibliography of his work on mollusks, with a catalogue of his recent molluscan taxa. Occasional Papers on Mollusks 4(58): 229-241.
  • Johnson, R.I. 1978. Systematics and zoogeography of Plagiola (= Dysnomia = Epioblasma), an almost extinct genus of freshwater mussels (Bivalvia: Unionidae) from middle North America. Bulletin of the Museum of Comparative Zoology 148: 239-321.
  • Johnson, R.I. 1979. The types of Unionacea (Mollusca: Unionidae) in the Museum of Zoology, The University of Michigan. Malacological Review 12(1): 29-36.
  • Johnson, R.I. 1980. Zoogeography of North American Unionacea (Mollusca: Bivalvia) north of the maximum Pleistocene glaciation. Bulletin of the Museum of Comparative Zoology 149(2): 77-189.
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