PUBLICATIONS: Available Now!
FWGNA Volumes 5 - 7
We are pleased to announce that Volumes Five, Six, and Seven of the FWGNA series are now available directly from the print shop at a substantial discount. 

Volume 5, by Dillon, Kohl, Winters, Pyron, Reeves, Watters, Cummings, Bailey and Whitman reports the results of a comprehensive freshwater gastropod survey conducted in the drainages of the Ohio, Cumberland, and Tennessee Rivers. We provide full-color figures, a dichotomous key, range maps, and natural history notes for all 80 species and 19 subspecies of freshwater snails recovered, updating the taxonomy to modern standards. A new continent-scale biogeographic analysis is offered, and the objective system of abundance ranking by incidence categories we proposed in Volume 1 is expanded and updated.  Three new species of cave-dwelling hydrobioid gastropods are described in the appendix.

Four Volumes
Volumes 6 and 7 are collections of essays, originally appearing in blog form 2019 - 2023, edited and rearranged thematically.  Volume 6 collects 32 essays on the systematics and evolution of the pleurocerid and hydrobioid snails of North America and Volume 7 comprises 36 essays on the ampullariids, viviparids, and pulmonates.  These volumes are essential companions to support and augment the scientific results reported in Volumes 1 and 5.

The total retail price for these three volumes if purchased individually would be $158.68.  But we have arranged a special package deal with the print shop for friends of the FWGNA project, available online


Hit the link below to "buy yours now."  That will take you to my author profile page at bookbaby.com.  At the bottom of my profile page you will find seven "titles by this author." Hit the links for Volume 5, Volume 6, and Volume 7 in turn, add each of those titles to your shopping cart separately, and apply the coupon code FWGNA3.  Then proceed to checkout. Your price will be discounted to $99.95 for the set ... a bargain!


FWGNA Volumes 1-4
The first four volumes in the FWGNA series, originally published in 2019, are still available from the print shop at a discount.

Volume 1, by Dillon, Ashton, Reeves, Smith, Stewart and Watson, reports the results of a comprehensive freshwater gastropod survey conducted in Atlantic drainages from Georgia to the New York line. We provide full-color figures, a dichotomous key, range maps, and natural history notes for all 70 species and subspecies of freshwater snails recovered, updating the taxonomy to modern standards. A new, objective system of conservation status ranking is proposed, and a new species of pleurocerid snail described in the appendix.

Four Volumes
Volumes 2, 3, and 4 are collections of essays, originally appearing in blog form 2003 – 2019, now edited and rearranged thematically.  Volume 2 collects 29 essays on the systematics and evolution of the freshwater pulmonates of North America, Volume 3 comprises 37 essays on the systematics and evolution of the prosobranchs, and Volume 4 collects 38 essays reviewing ecological and biogeographical themes.  These volumes are intended to support and augment the scientific results reported in Volume 1, as well as Volume 5 on the Ohio, Cumberland and Tennessee drainages, published subsequently.

The total retail price for the first four volumes in the FWGNA series, if purchased individually, would be $145.80.  But we have continued the special package deal that we first arranged in 2019 for friends of the FWGNA project, available online


Hit the link below to "buy yours now."  That will take you to my author profile page on the printer's website.  At the bottom of my profile page you will find seven "titles by this author," including the first four books we published in 2019 as well as the three we just published in 2023. Hit the links to Volume 1, Volume 2, Volume 3, and Volume 4 in turn, add each of those titles to your shopping cart, and apply the coupon code FWGNA4.  Then proceed to checkout.  Your price will be discounted to $99.95 for the set.








FWGNA Circulars
1.  Dillon, R.T., Jr. (2012) Toward the scientific ranking of conservation status.  FWGNA Circular 1: 1 - 13.  [pdf] The data are obsolete, but the introduction and methods remain important.

2. Dillon, R.T., Jr.  (2020) The four subspecies of Pleurocera troostiana (Lea 1838), with synonymy.  FWGNA Circular 2: 1 - 5. [pdf]  This is a summary document for the observations, arguments, and hypotheses I advanced in a series of six blog posts to the FWGNA Blog:
  • On The Trail of Professor Troost [6Dec19]
  • CPP Diary: The Many Faces of Professor Toost [7Jan20]
  • Huntsville Hunt [15Apr20]
  • A House Divided [10May20]
  • What is Melania edgariana? [5June20]
  • The Return of Captain Lyon [6July20]
3.  Dillon, R.T., Jr. (2021) Two keen Campeloma quizzes.  FWGNA Circular 3: 1 - 3. [pdf] Mostly just fun, but there's a serious subtext.  See my blog post:
    • Fun With Campeloma! [7May21]
4.  Dillon, R.T., Jr. (2022) The biogeography of North American freshwater gastropods, v1.0. FWGNA Circular 4: 1 - 5. [pdf] Originally published online in 2019, and rendered obsolete in 2022 by the publication of biogeography v2.0.  But the methodology remains interesting.

5.  Wethington, A.R., J.M. Rhett, and R.T. Dillon, Jr. (2022) Allozyme, 16S, and CO1 sequence divergence among populations of the cosmopolitan freshwater snail, Physa acuta.  FWGNA Circular 5: 1 - 36. [pdf] Previously unpublished, this manuscript reports the first evidence of cytoplasmic male sterility in Physa.  For more, see my blog posts:
  • Cytoplasmic Male Sterility in Physa! [9June22]
  • Cytoplasmic Male Sterility in the Snake River Physa [7Aug24]
6.  Liu, H-P. and R.T. Dillon, Jr. (2021) Resolving the species status of the Surprise Valley Pyrg (Pyrgulopsis gibba) and Vinyard Pyrg (Pyrgulopsis vinyardi).  Report to Stantec Environmental Consulting.  FWGNA Circular 6: 1 - 5. [pdf]  For background, see my blog post:
  • Just 125 Species of Pyrgulopsis in the American West [7Sept22]
7.  Dillon, R. T., Jr. (2018) Welcome to the mystery snail color genetics project!  FWGNA Circular 7: 1 - 13.  [pdf] In 2018 I initiated a crowdsourced effort to work out the inheritance of color polymorphism in the common aquarium pet, Pomacea diffusa.  This circular is a hardcopy version of an 11-page website I put online to guide potential volunteers through the experimental design.  For more, see:
  • The Mystery Snail Color Genetics Project [6June23].