Dr. Rob Dillon, Coordinator

Tuesday, March 23, 2004

Report from Tuscaloosa

I'm pleased to report that registration topped 100 at the FMCS gastropod workshop at the University of Alabama last week. The weather was warm, the facilities adequate, and our hosts most gracious. A good time was had by all.

FMCS president Tom Watters opened the water quality portion of the conference Monday and Ken Brown spoke on the status of freshwater snails in the southeast Tuesday, both talks I was sorry to miss. The meat of the gastropod conference was served on Wednesday, with 9 talks of 30 - 45 minutes each, organized systematically. The nice young folks making the presentations were all well-prepared and thorough, compensating for lack of experience with extra measures of enthusiasm. Perhaps the main message of the day was that identifying freshwater gastropods ain't brain surgery. A bit of background, a key reference or two, patience and willingness to learn are all one really needs. Here's a download of the workshop "Primer":

Perez, Clark, & Lydeard (2004) FMCS Freshwater Gastropod Identification Workshop [PDF]

Most of the Wednesday presenters were, to borrow Kathryn Perez's apt turn of phrase, "channeling Dr. Burch." The two exceptions were Amy Wethington, with her Ph.D. dissertation on the Physidae recently defended, and (of course) Jack Burch himself. Jack used the occasion to repeat his long standing quibbles with Hubendick's (1951) monograph on the Lymnaeidae, arguably the greatest work on any family of mollusks ever published. He prefers a modification of the systematic arrangement of F. C. Baker which, innocent of the modern synthesis, was based almost entirely on shell characters. Jack reviewed some micro-Ouchterlony results he obtained years ago which seem to support the Baker classification. I would love to see these data published in the peer-reviewed literature, where they might be objectively evaluated.

Amy Wethington has 15 years of direct experience with the Physidae and co-authorship of about a dozen peer-reviewed papers on various aspects of their biology. Her classification, based on hundreds of DNA sequences, allozymes, anatomy, reproductive biology and ecology, would reduce the number of North American species from 40 to about 10, and genera from four to two. Oddly, the editors of the meeting's Gastropod Identification Workbook preferred* the 23 - genus classification of Taylor (2003), based on features of penial anatomy only Dr. Taylor can see, which if they exist, are demonstrably immaterial to the snails themselves. Amy paid for a 20-page supplement out of her own pocket, fairly and objectively reviewed all competing classifications of the Physidae, and emerged as the hero of the meeting. Here's a download of Amy's Supplement:

Wethington, A. R. (2004) Family Physidae [PDF]

Thursday's presentations dealt with overarching topics, especially taxonomic methods and ecological applications. The highlight of the day for me was a dispatch from the front lines of freshwater gastropod conservation couriered by Steve Ahlstedt and Paul Johnson. Steve reviewed his many years of transplantation experiments with Io, and Paul reported his more recent successes with captive propagation. I used my presentation on freshwater gastropod distribution and ecology to introduce a new web resource, the Freshwater Gastropods of South Carolina.

A nice variety of freshwater gastropods, both the living and the dead, kept mute witness on the side tables during the two day event. The "show-your-shells" social Wednesday evening was a big hit - I myself learned quite a lot from the interesting assortment of specimens carted to Tuscaloosa from the four corners of this great land. Laurels are due to meeting chairman Chuck Lydeard and his hardworking young colleagues David Campbell, Stephanie Clark, Kathryn Perez and Jeffrey Sides. Well done everybody!

*P.S. Chuck Lydeard has asked me to forward to the group an explanation for his choice of the Taylor classification over the Wethington classification for the Physidae chapter of FMCS Workbook. Apparently it was easier to format the poorer classification to fit strict workbook guidelines.

---------[From Chuck Lydeard 25Mar04]-------------

As co-editor of "A Primer to Freshwater Gastropod Identification" (Perez, Clark, and Lydeard), I would like to explain our decision to opt for Taylor's (2003) classification scheme of the Physidae for the workbook. First, we chose to adopt rather strict guidelines for ALL authors to follow including a brief introduction of the family, a small table giving a few species and their conservation rank, and a general description and illustration for each genus in the family. The oral presentations were also supposed to adhere to the guidelines offered for each family account. Taylor (2003) offers the latest published account of the family. Taylor's anatomical renderings for each genus are very useful and provide an opportunity for the reader to see the entire male reproductive tract with labels. Taylor has about 40 years of experience with freshwater mollusks including physids, so he is certainly knowledgeable about the group. Of course, our use of Taylor (2003) should not be construed as an endorsement of his findings, nor should it be construed as a dismissal of Amy Wethington's dissertation findings. I was Amy's dissertation advisor, so I certainly appreciate and value what she accomplished during her time as one of my graduate students. However, I did not think all the intra-generic details she was willing to provide was necessary for the workbook and certainly would have altered our format appreciably. In closing, we are pleased with the workbook and feel it fulfills its purpose as a primer to gastropod identification reasonably well. We hope you will all look to the future for published phylogenetic studies about various freshwater families of gastropods.

Chuck Lydeard

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