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Date:         Fri, 30 Dec 2005 19:17:15 -0500
Reply-To:     Conchologists List <CONCH-L@LISTSERV.UGA.EDU>
Sender:       Conchologists List <CONCH-L@LISTSERV.UGA.EDU>
From:         "Harry G. Lee" <shells@HGLEE.COM>
Subject:      Re: "rare" and valuable shells and  heedless destruction.
Content-Type: multipart/alternative;

Dear Guido et al.,

In contrast to of aquatic mollusks, of which many dozens have become extinct through the environmental deterioration wrought by man, marine mollusks are quite resilient as Guido indicates. While I don't wish to detract from this biological fitness of these sea-dwelling species, I am compelled to comment on the sentence following Guido's pronouncement: "At present, we know of NOT A SINGLE MARINE SPECIES extinct by humans," with which I agree. He went on to write: "At one moment there was discussion about a northern American limpet, but it was found again recently," and that statement warrants clarification.

We began the discussion of the Bowl Limpet (Turgeon Quinn, et al., 1999), Lottia alveus alveus (Conrad, 1831) in this forum over seven years ago. This species-level taxon lived a monotonous but prosperous life attached to the marine Eelgrass, Zostera marina (Linnaeus), in extensive beds along the northeast coast of North America from Long Island to Labrador - that is until 1930, when a plague of slime mold infestation catastrophically reduced the plant populations, leaving the survivors only in brackish backwaters where the parasite (and regrettably the Bowl Limpet, its obligate epibiont) could not survive. No specimen of Lottia alveus alveus has been collected since 1929, when it was known to be abundant.

To my knowledge, its taxonomy has not been questioned since Carlton, Carlton, Dudley, Lindberg, and Vermeij (1991) distinguished it from northwest American [Lottia alveus parallela (Dall, 1914)] and northeast Asian [L. alveus angusta (Moskalev, 1967)] populations. I haven't heard of any rediscovery of Lottia alveus alveus (Conrad, 1831), but (1) I may have missed something or (2) the northern Pacific subspecies might be (incorrectly) considered as evidence, one way or another, against the extinction of the Bowl Limpet.

A all-too-infrequent contributor to this form, Kevin Cummings, wrote us in 1999 [slightly edited]: "As the topic of rarity was discussed recently I thought that this article [Roberts and Hawkins, 1999] might be of interest to some in the group. The authors make the case that marine species could be at a far greater risk of extinction than previously assumed. The only documented extinct marine species cited was the eelgrass limpet, Lottia alveus alveus, but they cite others on the verge."

Lets hope that our species, by heeding the admonition of the Robertses and Hawkinses of the world doesn't ever refute Guido's pronouncement.


Carlton, J., 1993. Neoextinctions of Marine Invertebrates. American Zoology, 33, 499-509. Carlton, D., J. Carlton, E. Dudley, D. Lindberg, and G. Vermeij, 1991. The first historical extinction of a marine invertebrate in an ocean basin: The demise of the Eelgrass Limpet, Lottia alveus. Biological Bulletin 180: 72-80. Gould, S. J., 1991. On the loss of a limpet. Natural History [vol. and no.?]: 22-27. June. Roberts, C. M., and J. P. Hawkins, 1999. Extinction risk in the sea. Trends in Ecology and Evolution 14(6):241-246.

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. ix + pp. 1-509 + 16 pls. (unpaginated).

At 02:12 PM 12/30/2005, Guido wrote: I cannot agree on that. I think not even 5 % of the coasts of Australia have been properly explored for shells. There are so few people diving professionally and the costs in getting these shells are so high that these rather explain the price than the rarity. I agree that some populations can be truly devastated in small corners... and I also agree that quality is so important that a shell with growth line, sand grains etc.. is worthless. Especially in the thersites they are good for the garbage. We make a point on Guphil I by not collecting damaged shells, unless the crew wants to eat them.

At present, we know of NOT A SINGLE MARINE SPECIES extinct by humans. At one moment there was discussion about a northern American limpet, but it was found again recently.

Instead of pointing the finger to collectors one should think about the truly destroying things, such as building a town along the coast.

Guido Harry G. Lee, M.D. Suite 500 1801 Barrs Street Jacksonville, FL 32204 USA voice (904) 384 6419 fax (904) 388 1827 email:


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