The Western Pyrgulopsis: 151 planets in the sky?

I love retirement for many reasons, not the least of which is that it is a good excuse.  I very rarely submit grant proposals or papers to scientific journals anymore, and so very rarely volunteer to review anybody else’s.  I do not attend meetings because – you know – fixed income!  And as for serving on committees, boards, and panels, I have paid my dues.

Pyrgulopsis neritella (A,B) and landyei (C-F). From [1]

But on 28Sept26 I received a courteous email from a Dr. Jacob Burkhart from the US Fish & Wildlife Service, Midwest Regional Office, out in Minnesota somewhere, I think.  He explained that he was working on a team that is completing a “Species Status Assessment for several Pyrgulopsis springsnail species found in the Steptoe Valley of Nevada,” and asked me if I “would be willing to provide a peer review” of their “proposed treatment of springsnail taxonomy.”  And my rusty old armor cracked open just a bit.  His situation was just so pathetic.

So here is my reply, verbatim:

“Well, OK.  One of my favorite quotes in the history of the world comes from Dr. Seuss’ Cat in the Hat: ‘This mess is so big, and so deep and so tall, We cannot pick it up. There is no way at all.’ But I suppose it is my duty to help you try.”

So on 2Oct26 my new friend Jacob sent me a 6-page document entitled “NV Springsnails Taxonomy Summary For Peer Review."  In this document he and two FWS colleagues briefly reviewed their motivation, which turned out to be rooted in that “Megapetition” from the Center for Biological Diversity we reviewed way back in [14July09], see also [18May11].  Jacob and colleagues then soldiered bravely through thirty years of scattered, disorganized, ambiguous, confusing and contradictory gobbledygook, ultimately resolving to “evaluate the following entities for the purposes of this SSA report: P. landyei, P. neritella, P. sulcata, P. sterilis, and P. CS28.”  Bless their hearts.

 

And along with his little document for review, Jacob attached a huge bolus of supporting materials, including an important paper by Mike Young and five colleagues [2] that I will confess to you right now, I had been cravenly avoiding.

 

In early August I had received a comment from Mike at the bottom of my [7Sept22] post to this blog, “Just 125 of Pyrgulopsis in the American West.”  See note [3] about my species count.  I had prophesied that “One day, I feel sure, somebody will come behind (Bob Hershler) and test the 125 (Pyrgulopsis species) that remain.”  And I had concluded “I cannot imagine when, or by whom.  Not it.”

 

In August, Mike Young had answered, “We did it. And it appeared yesterday in Western North American Naturalist.”  To that comment I responded, “Great news! Could you send me a pdf?”  Alas, his answer turned out to be no.  And my effort to download a copy for myself was defeated by a paywall.

 

One of the very few things I do not love about retirement is that I have lost my access to most of the scientific literature being published today.  Sure, I could impose on colleagues in higher education to download a pdf for me, and occasionally I do.  Or, I could kick the Pyrgulopsis can down the road, and pray that the Son of Man might Return in all His Glory before I ever saw it again.

P. neritella (1.3 mm), P. landyei (1.4 mm). From [1]

Mike Young had been most cooperative when I reviewed his 2021 paper on Physa [5] back in 2024, and I knew him to be a hard worker, with excellent technical skills.  I had been impressed both by the quality and the quantity of the data he had gathered for that research effort, especially by the rigor with which he documented every nucleotide in every sequence, and every point to the right of the decimal in every sample site.  He was breathtakingly naïve regarding the biology of his study organisms, and pristinely ignorant of the published literature.  Consequently, he was utterly unable to state an hypothesis, much less test one.  But I was.  And in Mike Young's gigantic trash-snail dataset I discovered a light sprinkling of rare cases bearing directly on the point of important hypotheses.

 

It was a lot of work to mine the diamonds from a mountain of physinine slag, however, and I just was not sure I heard the call to do it again.  The Pyrgulopsis mess is today an order of magnitude worse than the Physa mess was at the dawning of my career, and going in the wrong direction.  Burch’s 1980 Bible [6] listed 16 species of Pyrgulopsis/Fontelicella in North America, and 65 species and subspecies of Physa.  Today we [7] count seven good, biological species of Physa [8], and 151 species of Pyrgulopsis.

 

Don’t get me wrong.  Science is the construction of testable hypotheses about the natural world.  To the extent that our current hypothesis about the western Pyrgulopsis is testable, it is science.  It is the intellectual equivalent of looking into the heavens and describing 151 planets, wandering randomly across the night sky [9].

 

Now here was Mike Young’s Pyrgulopsis paper laid out before me, with all 13 of his supplements in a zipped folder beside, and no sound of the trump, and I was clean out of excuses.  So, I dove in.  And I have never, in a professional career spanning over 50 years, ever laid eyes upon a more splendid dataset, a more cringeworthy analysis, or a more amazing result in the long and glorious history of freshwater gastropod population genetics [10].

 

First, the splendid dataset.  Mike and his colleagues sampled 4,270 individual Pyrgulopsis from 644 locations.  All were sequenced for the mitochondrial COI gene.  And “from each COI clade exhibiting a marked level of divergence and represented by more than one individual” Mike Smith sequenced one or more of three additional genes, mitochondrial ND1, nuclear ITS2 and nuclear 28S. 

 

To these 4,270 lines of data Mike and colleagues added 1,362 Pyrgulopsis sequences previously published, mostly of COI but a smattering of others.  And his entire 5,632-line [11], 22-column data set he made available as an excel spreadsheet in his Supplementary Material 2.  Splendid.

The 644 sample sites of Young et al. [2]

Regarding Mike Young’s analysis, it was, in two words, baroquely arbitrary.  Young characterized his species concept as “phylogenetic… requiring reciprocal monophyly” while specifying “an additional requirement for species-level rather than population-level divergence,” which is so obviously circular one wonders how such reasoning could be entertained in Western thought.  The application of this concept turned out to require such mental gymnastics such as: 

“Requiring reciprocal monophyly for the P. pilsbryana species complex would have resulted in recognizing all specimens as members of the type species, despite many populations exhibiting levels of divergence that were characteristic of valid species among other members of this genus.”

And how, one might wonder, did Mike Young determine that "characteristic" level of species divergence, which seems to have been violated in what he decided a priori must be a P. pilsbryana “complex?”

The best way to summarize Mike Young’s baroquely-arbitrary analysis is to look back from a sample of his results.  The figure below is a tiny slice off the top of Young’s Figure 2, which is intended to relay the results for his Pyrgulopsis pilsbryana “species complex.”  At left is the maximum-likelihood COI tree showing six clusters.  The seven rows of boxes at right relay the results of his “identification of candidate species.”  This little subset of seven nominal species includes four previously-described (bedfordensis, blainica, ignota, and fresti), the daggers by ignota and fresti indicating that they are “not considered part of the pilsbryana complex,” apparently interlopers from some other “complex” unspecified.  There are also two candidate species as yet undescribed (CS21 and CS22), and one “informal group” sampled from Brush Creek “not assigned to a candidate species.”

I do not know how the six COI clusters at left map onto the seven candidate species at right.  Has the “informal group” from Brush Creek been subtracted from the gene tree?  We’ll let that go and soldier on.

Young et al. [2] Figure 2, detail.

Each of the seven rows has 11 columns, each column corresponding to one “species delimitation method.”  For a key to the 11 such methods, see Young’s complete Figure 2 caption at footnote [12].  Orange boxes indicate that this particular COI clade was delimited as a species, gray means no, white means no data, and an asterisk indicates “more than one taxon within the clade.”

 

And the main result I would like to highlight is this.  Six of the seven “candidate species” shown in this tiny slice off the top of Young’s results were in fact subsequently listed in his Table 1 as “valid,” all but that "informal group" from Brush Creek.  This despite the fact that no data were available for anything other than COI sequence for bedfordensis, blainica, fresti, or the as-yet-unnamed CS21 whatsoever.

 

Mike Young’s baroquely-arbitrary classification system ultimately devolved to ad hoc binning on the basis of one, single character.  On COI sequence alone [13], he and his colleagues ultimately listed 21 Pyrgulopsis species as “candidates for synonymy” and identified 17 “previously unrecognized clades” that “were delimited as candidate species,” for a net decrement of 4 species.  Our 151-planet hypothesis is now a 147-planet hypothesis.

 

I belong to an elite generation of evolutionary biologists who are old enough to have been influenced by Sneath & Sokal's numerical taxonomy [15], but not so old as to have forgotten it.  And vividly I remember how systematic biologists of that age used to rage against “single character classifications.”  Even given a genetic basis for the character being analyzed, it was universally understood fifty years ago that populations are the unit of evolution, and universally appreciated that populations demonstrate genetic variation both within and among, and with but a single character any interspecific variance that might be attributable to reproductive isolation cannot be recognized.

 

Note that I said above, “To the extent that our current hypothesis about the western Pyrgulopsis is testable, it is science.”  The bottom line is that Mike Smith’s cringeworthy analysis does not constitute a test.

But stepping back from the species hypothesis entirely, and simply understanding a COI sequence as the single genetic marker that it is.   We have now arrived at Mike Young’s amazing result, and the grand finale of the present essay.  Quoting him verbatim: 

“And given the fairly frequent co-occurrence of taxa—at 100 of the 1101 sites in this study, which is a minimum estimate—more thorough collecting and analysis of specimens from single sites is also warranted.”

Holy crap, could that be true?  The model of the Western Pyrgulopsis I have always borne in my mind has been one of complete allopatry.  One single nominal species per spring, never any more, right?  But returning to Mike’s big Supplement #2 spreadsheet, sorting by location and running an eager finger down the first 1,000 rows or so, I counted six sample sites at which more than a single COI haplotype was discovered.  Wow.  That is quite simply, and quite profoundly, amazing.

 

Mike labeled each COI haplotype as a different “delimited species.”  And in so doing, he unwittingly committed an act of science.  He constructed an hypothesis about the natural world that can actually be tested.  Next month, we test it.

 

Notes:

 

[1] Hershler, R. (1998) A systematic review of the hydrobiid snails (Gastropoda: Rissooidea) of the Great Basin, western United States. Part I. Genus Pyrgulopsis. The Veliger 41: 1-132.

 

[2] Young, Michael K.; Pilgrim, Kristine L.; Miskow, Eric S.; Lundskog, Chante L.; Perez, Kathryn E.; and Schwartz, Michael K. (2026) "Molecular refinement of the taxonomy of Pyrgulopsis springsnails in western North America," Western North American Naturalist: Vol. 86: No. 2, Article 10.  Available at: https://scholarsarchive.byu.edu/wnan/vol86/iss2/10

 

[3] In my Bob Hershler essay of [6July22] I counted N = 126 species of Pyrgulopsis in the American West by paging through his (2017) “Annotated Checklist” [4].  Apparently molluscabase.org lists N = 151.  I have no insight to offer regarding the origin of this discrepancy.

 

[4] Hershler & Liu (2017) Annotated Checklist of Freshwater Truncatelloidean Gastropods of the Western United States, with an Illustrated Key to the Genera.  US Bureau of Land Management Technical Note 449: 1 – 142.

 

[5] Young, M.K., R. Smith K.L. Pilgrim, and M.K. Schwartz (2021) Molecular species delimitation refines the taxonomy of native and nonnative physinine snails in North America.  Scientific Reports 11: 21739. https://doi.org/10.1038/s41598-021-01197-3.  For my review, see:

• The SRALP and the SRNLP: A new hope [14May24]
• The SRALP and the SRNLP: Physa acuta were found [11June24]
• The twelve phascinating Physa of Bliss [2July24]
• Cytoplasmic male sterility in the Snake River Physa [7Aug24]

[6] This is a difficult work to cite. J.B. Burch’s North American Freshwater Snails was published in three different ways.  It was initially commissioned as an identification manual by the US EPA and published by the agency in 1982.  It was also serially published in the journal Walkerana (1980, 1982, 1988) and finally as a stand-alone volume in 1989 (Malacological Publications, Hamburg, MI).

 

[7] The clarity brought to the Physa of North America is in large part due to the many years of laboratory and field effort logged by myself and my students, the likes of which I could never hope to match with Pyrgulopsis in what remains of my sojourn in this World of Woe.  It is true that a smattering of samples have passed across my lab bench in recent years.  But I must confess, I have never seen a Pyrgulopsis on the hoof.  So, let’s give that jumbo 28-oz can of Bush’s Baked Pyrgulopsis another swift kick, okay? No?

 

[8] The confirmed species of Physa in North America are: acuta, carolinae, gyrina, jennessi, pomilia, vernalis, and zionis.  One might also count Aplexa elongata as number 8. The jury is still out on ancillaria/parkeri. 

 

[9] Without the entry of a single new datum into evidence, Galileo and every other astronomer peering into the night sky of the seventeenth century immediately discarded Ptolomy’s geocentric model of the heavens and embraced Copernicus’ heliocentric model.  Two reasons.  First, the heliocentric theory is powerful, yielding strong predictions about the behavior of planets as yet undiscovered and capable of rejecting planets that cannot exist.  And second, the heliocentric theory is elegant.  I do not understand what has happened to our profession in these latter generations, but I do know this.  Most of the faculty in the university science departments and research institutes of today would not know a theory – elegant, ugly or otherwise – if it bit them on the bottom.

 

[10] Mike Young’s discovery of significant sympatry in the western Pyrgulopis fauna scored 94.1 international amazingness units, edging out the 93.2 iau scored by Bianchi and colleagues back in 1994.  For a complete ranking of the top five, see:

• The third-most amazing research results ever published for the genetics of a freshwater gastropod population [1].  And the fourth-most amazing, too. [3Mar22]

[11] The excel spreadsheet downloadable as Supplementary Material 2 does indeed contain 5,632 lines, but only 5,631 are data, line #1 being the column labels.  Apparently the gene sequence(s) from one individual Pyrgulopsis have been lost, for an error rate of 0.018%

 

[12] The complete caption of Figure 2, from [2]:  "Identification of candidate species for most members of the Pyrgulopsis pilsbryana species complex, structured following highly supported clades (branches with red dots and all collapsed nodes have bootstrap support >85) from the maximum-likelihood tree for the COI gene fragment. Taxa in bold are hypothesized candidate species; those marked with a dagger are not considered part of this complex (see text). Each column depicts the results of 1 species delimitation method (A, ASAP; P, Poisson tree processes; S, statistical parsimony networks) for mitochondrial data (COI, ND1, or the concatenated sequences [CON]) or diagnosability (D) and substantial molecular support (B, bootstrap support ≥85) for nuclear data (ITS2 or 28S). Cell fill denotes whether a COI clade was delimited as a species (orange, yes; gray, no; white, no data). A cell with an asterisk denotes that more than 1 taxon within the clade was delimited. Vertically oriented labels indicate informal group membership for specimens not assigned to a candidate species."

 

[13] Well, to be completely accurate.  One of the species Mike proposed for synonymy was P. vinyardi, under P. gibba.  That confirms the result Hsiu-Ping Liu and I published in the gray literature back in 2021 [14], finding no evidence of disequilibrium between COI and penial morphology.  So in the single particular case of P. vinyardi, the evidence of synonymy is more than just mtDNA sequence.

 

[14] Liu, H-P, and R. T. Dillon, Jr. (2021) Resolving the species status of Surprise Valley Pyrg (Pyrgulopsis gibba) and Vineyard Pyrg (Pyrgulopsis vinyardi).  Report to Stantec Environmental Consulting. FWGNA Circular 6: 1 – 5. [pdf]  For a review, see:

• Just 125 species of Pyrgulopsis in the American West [7Sept22]

[15] Sneath, P.H.A, and R.R. Sokal (1973) Numerical Taxonomy: The Principles and Practice of Numerical Classification.  W. H. Freeman. 573 pp.  

The ICE Detention Center and the Snail

OK, listen up!  It seems likely to me that the title of this month’s essay may attract more than the usual trickle of casual surfers and random googlers to this arcane little crack in the internet.  You new visitors and guests will not find anything newsworthy in the paragraphs that follow, nor any information relevant to any ongoing controversy, nor anything interesting, entertaining, nor probably even intelligible.  And absolutely no politics!  This is a blog post written by a snail scientist, for snail scientists.  Everybody else, please go away.  You’re scaring us.

Now for my colleagues still remaining, all six of you all.  Here is the background.  In the late morning of Wednesday 1Apr26 [1] I missed two phone calls but did successfully receive a voicemail and a follow-up email from one Ms. Maddi O’Neill with the subject line, “Media request on deadline.”  In her email, Ms. O’Neill identified herself as a freelance journalist based in Baltimore. And here, verbatim, is the background she supplied, which is really all I know about the political controversy to this day:

“I'm working on a story about a proposed ICE detention center in Washington County, Maryland, and the state of Maryland's effort to block its construction through litigation. Maryland's lawsuit hinges on the need for an Environmental Impact Statement, which the feds have not completed, and points to possible harms to state-endangered species and species in need of conservation that live near the proposed detention center site. Specifically, the state references [2] … the Appalachian springsnail, and I was wondering if you'd be open to speaking with me for a story.”

A quick google search on my part reminded me [3] that the “Appalachian springsnail” is Fontigens bottimeri.  For background on the biology of that obscure little black speck of a gastropod see the FWGNA [species page], and for contextualization see my essays of [9Aug22] and [12Feb26].

At the Hopewell Road entrance.

So I returned Ms. O’Neill’s phone call right away, and we arranged a convenient time for a telephone interview a couple days later, Friday morning 3Apr26.  In the interim, I did a bit of homework – googling up more info on the proposed ICE Detention Center, located on a 54-acre site in the crotch of I-81 and I-70, just north of Williamsport. 

I initially labored under the false impression that the feds were proposing to construct a new facility.  But in fact, their proposal was to repurpose an 800,000 square foot warehouse already on that site, newly constructed (on speculation? really?) but never used [7].  The monstrosity was large enough to have two addresses: 10900 Hopewell Road and 16220 Wright Road.

And digging through the FWGNA database, I found a Fontigens bottimeri record in the Smithsonian (USNM-874706) collected by one D. Feller in 1991 from “Kemps Spring No. 4,” the lat/long coordinates of which (39.6136, -77.8136) mapped just a half mile East of 16220 Wright Road.  I also took the opportunity to email my buddy Matt Ashton at the Maryland DNR for his input but received no response [8].

I really enjoyed getting to know Ms. Maddi O’Neill, however, in our roughly 30-minute telephone conversation Friday.  It turned out that she herself was planning a field trip to hunt Fontigens in the waters around the proposed detention center.  I like that sort of positive mental attitude.  I did my best to help her over the phone, emphasizing that Fontigens populations are restricted [9] to springs and spring runs – cold, clear, pristine 100% groundwater.

And I was pleased to receive a couple follow-up texts from Ms. O’Neill Sunday afternoon 12Apr26, apparently in the field, asking for the lat/long coordinates of Kemps Spring #4, and following with several photos of individual Lymnaea humilis perched on her finger. Bless her heart!

So on 27Apr26 she texted me a link to her article, newly published in an online magazine called “Slate,” [html].  I found the article behind a paywall.  But I was so curious to read it that I ponied up the dough for a three-month subscription, so I could copy-and-paste the text into a [pdf] document, here:

An Ingenious New Strategy for Blocking ICE Detention Warehouses Depends on a Minuscule Snail, by Madeleine O’Neill.

Spoiler alert!  Our friend Maddi did not find any Fontigens bottimeri.  But by that point I had already made plans to drive up I-81 to Williamsport and do the survey right.

I laid out a sampling scheme with five sites down Semple Run (A, B, C, D, F), the little stream just beneath the gigantic warehouse at 16220 Wright Road.  I had also noticed, using the yellow man on Google street view, what looked like an old springhouse by Wright Road not 100 yards down the hill from 16220 (E). And of course, I dropped a pin (G) on 39.6136, -77.8136.  At which coordinates I could find no evidence of a spring on any map available to me.  Satellite imagery seemed to suggest that point was in somebody’s back yard.

So the bright sunny morning of Tuesday, 5May26, found me touring around the besieged little valley of Semple Run.  And the first entry into my field notebook was this: “Semple Run low and clear over silt and debris. 150 years a ditch through ag fields, a ditch under the interstate thereafter.”

Marl falls at Site (D).

From the topo maps, it had seemed possible to me that Semple Run might bear a lot higher proportion of groundwater than it actually carries here in the 21st Century.  The current picked up speed downstream, over a cobble bottom, with some marl.  But alas, at no point was the environment fit for Fontigens, headwaters to mouth [10].  I found patchy populations of the usual Physa (both acuta and gyrina) and Maddi’s Lymnaea (Galba) humilis in the five sample sites I had marked down its length, and (quite unexpectedly) a couple individual Helisoma trivolvis, doing the anceps job. No limpets.  Period.

And perhaps unsurprisingly, the Wright Road springhouse (E) was bone dry, alas again.  The ground was boggy below the springhouse, on the other side of Wright Road, no habitat for Fontigens in evidence.

Springhouse at Site (E).

And what of Kemps Spring #4?  I parked at the south end of Celeste Drive, walked over the railroad tracks, and knocked on the door of the lovely circa 1820 brick farmhouse at 39.6136, -77.8136, repeatedly.  And a dog inside barked loud enough to wake the dead.  And nobody came to the door.  So, I let myself through the gate into the back yard and toured around, finding no evidence of spring nor springhouse.

Ultimately a nice lady, in her dishabille (as my mother used to say) came out to greet me [11].  She confirmed that no spring exists on her property, nor has any spring ever existed in that neighborhood to her knowledge, although she was familiar with the dry springhouse at Wright Road, on the other side of the tracks.  It seems likely to me that the dry springhouse at site (E) was indeed built over Kemps Spring #4, with an error of 0.0012 degrees latitude and 0.0070 degrees longitude.

Big farmhouse at Site (G).

“Lovely farmland spoiled.”  That’s the last note in my field book for the morning of May 5, 2026.  And back at the truck, as I shucked off my boots, it occurred to me that same observation would apply equally to the country around my own hometown of Waynesboro [12], two hours south, in the same sprawl that has enveloped the country around Williamsport.  And indeed, sadly, the Great Valley of Virginia.  And as one of my favorite philosophers once observed, “If this valley is lost, Virginia is lost.”  And if Virginia is lost, what of America?

Notes:

[1] Yes, the thought that this might be an April Fool’s joke did occur to me.

[2] Ms. O’Neill also mentioned “the brook floater mussel, the green floater mussel,” as well as “a few species of fish.”

[3] Somewhat startlingly, the “AI overview” at the top of my google results for “Appalachian springsnail” referred back to me, myself, in a pdf document I posted on my own FWGNA site for the Commonwealth of Virginia back in 2011 [pdf].  At the request of my buddy Brian Watson, I had included the common name below the scientific name.  Otherwise, none of the other nine hits on the first page my google search for “Appalachian springsnail” were relevant [4].

[4] By contrast, my exploratory search for “Fontigens bottimeri” returned much more relevant information, including my species page on the FWGNA site.  In fact, from my search on Fontigens bottimeri I found the relevant US FWS species page, at which F. bottimeri is called the “Potomac Springsnail [5].”

[5] Whose ridiculous idea was it [6] to conjure out of thin air an elaborate parallel taxonomy of “common names” for obscure little creatures that legitimately have no common name?  When I was in fifth grade, my teacher explained that the binomial system of nomenclature was proposed by Linnaeus in 1753 to solve the chaos of multiple common names for the same organism.  Now it is happening again!  We have two “common names” for the same tiny little black speck-snail that never had a common name to begin with.

[6] Turgeon, D.D., J.F. Quinn, A.E. Bogan, E.V. Coan, F.G. Hochberg, W.G. Lyons, P.M. Mikkelson, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G. Thompson, M. Vecchione, and G.D. Williams (1998) Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks (second edition), American Fisheries Society Special Publication 26, Bethesda, Maryland, 526 pp.

[7] A deserted warehouse on the edge of town, seriously?  Staffed with henchmen, wearing black turtleneck sweaters, perhaps?

[8] I followed up with Matt on Tuesday morning 4/28.  He replied that “Because the State, and specifically the Secretary of DNR, is party to an ongoing lawsuit, I referred your inquiry to our Public Relations Manager, Gregg Bortz.”  I have yet to hear from Mr. Bortz.

[9] To be complete, F. nickliniana populations in the East and F. aldrichi in Missouri can extend some significant distance downstream.  But F. bottimeri populations, in my limited experience, are restricted to the springhead and immediate spring run.

[10] See Maddi’s April 27 article for a nice photo of Semple Run tumbling under Celeste Road at Site (F).

[11] I did apologize, sincerely and profusely.  Okay, it was 8:30 AM, still early, I suppose.  I honestly thought that all the racket I made on her front porch would have brought her to the door, but no.  I did not get her name.

[12] See here for a tribute to my home town of Waynesboro, Virginia:

• The Clean Water Act at 40 [7Jan13]

Horton hears two new species of Fontigens

Wanted: Collaborator.  Washed-up malacologist tragically enthralled by The Modern Synthesis of Darwin + Mendel seeks bright young evolutionary biologist with good molecular skills and the patience to (1) slog through last month’s discursive essay, (2) wade through this month’s ridiculous essay as well, and (3) write a grant proposal accordingly.  Apply within.

Last month [12Feb26] we refreshed our collective memory on the seven species of the hydrobioid genus Fontigens that were known, at the close of the twentieth century, to inhabit caves, springs, and spring runs in the Great Valley of Virginia [1], including one that isn’t a Fontigens but should be [2], and one that hasn’t been confirmed from the Great Valley but could be.

F. malabadi, Repass Saltpetre Cave

And we reviewed the mighty works of our heroes, Wil Orndorff and Tom Malabad of the VaDCR, collecting 87 samples of tiny gastropods from caves and springs in The Great Valley 2013 – 2019 [3] and delivering them in good order to my Charleston doorstep in three batches 2018 - 2020.  Five of those samples, collected from caves in Scott and Giles Counties, contained Fontigens that were unique to my eyes, which I dissected, described, and forwarded onward to our colleague Hsiu-Ping Liu in Colorado for sequencing.  Our description of three new species was published in 2023 [4], bringing the Valley total fauna of phreatic hydrobioids up to ten.

What I did not mention last month is that one single sample, collected from Repass Saltpetre Cave in Bland County in 2019, was of a population of Fontigens bearing shells unique to my eyes, that I forwarded on to Hsiu-Ping for sequencing, from which she was unable to amplify any DNA.  Disappointed, I settled for an identification of Fontigens-orolibas-question-mark and dropped it.

And what I concluded last month’s essay with was a teaser, strongly implying that we had not heard the last of Tom Malabad and Wil Orndorff.  For their explorations of the caves, karst features, springs and spring runs of the Great Valley of Virginia have continued, even unto the present day.  And on September 24, 2024, another big batch of 52 tiny vials, each containing even bigger batches of even tinier snails, floated down upon my Charleston doorstep light as Horton’s speck.

That batch of 52 samples, collected 2020 – 2025, contained 19 vials of snails that my daddy would have dismissed as “no count” – land snails, freshwater gastropods more common in above-ground waters, and one Fontigens too busted up to identify.  Then in the 33 samples of consequence, I identified 35 populations of phreatic gastropods: 10 Fontigens orolibas, 4 F. nickliniana, 4 F. bottimeri, 3 F. morrisoni, 3 Holsingeria, 2 F. tartarea, 1 F. hershleri [5], and 8 populations of Fontigens bearing shells unlike any I had ever seen before. Almost.

Now to be quite precise.  Among those 52 samples were a pair of fresh samples, one collected in 2022 and another in 2024, from that same peculiar population inhabiting the waters of Repass Saltpetre Cave in Bland County I had flagged several years previous.  The shells borne by the Fontigens in that pair of samples reinforced the impression of uniqueness that had first struck me in the 2019 sample, characterized by tighter whorls, a smaller body whorl, and a higher spire than any Fontigens previously described.  See the figure up at the top of this essay.

Gallohan Cave #1

And also among the 52 vials that arrived on my doorstep in September were a pair of samples collected 22Jan25 and 5Aug25 from The Caverns of Natural Bridge Village in Rockbridge County, bearing shells that matched the Repass Saltpetre population. And good grief!  In a third vial, collected in 2021 from Gallohan Cave #1 way down at the tip of Virginia in Lee County, I found a mixture of 5 Holsingeria and 2 Fontigens (red arrows above) bearing that same, peculiar Repass Saltpetre shell morphology.

Here I describe a new species, Fontigens malabadi Dillon MS, in honor of my esteemed colleague Thomas E. Malabad.  The shell of Fontigens malabadi is distinguishable from that of all previously-described species in the genus by relatively tight, rounded whorls, a small body whorl, and a high spire.  The type locality is a stream in Repass Saltpetre Cave, Bland County, Virginia.  Other populations of F. malabadi are known from cave streams in Rockbridge County and Lee County, Virginia.

F. orndorffi, Kinzer Hollow Cave

But wait, there’s more.  Also among the 52 vials delivered to my Charleston address in September were three samples of Fontigens bearing shells really, seriously unlike anything I had ever seen before, not just in the published literature but in all 87 samples collected by Wil & Tom 2013 – 2019.  These were collected from Spangler Cave and Kinzer Hollow Cave way down south in Lee County, and in Rogers Belmont Cave way up north in Warren County, Va.  That last sample, just a single individual actually (red arrow below), was mixed with two individual Fontigens orolibas.

Here I describe a second new species, Fontigens orndorffi Dillon MS, in honor of my esteemed colleague William D. Orndorff.  The shell of Fontigens orndorffi is distinguishable from that of all previously-described species in the genus by relatively tight, flat-sided whorls, a small body whorl, and a high spire.  The type locality is a stream in Kinzer Hollow Cave in Lee County, Virginia.  Other populations of F. orndorffi are known from streams in Spangler Cave (Lee County) and Rogers Belmont Cave (Warren County).

Rogers Belmont Cave

These are but manuscript descriptions at present.  As I noted in last month’s essay, in this day and age it is irresponsible to formally describe a new species without genetic confirmation of some sort.  And I have none.

But let me stop right here, back out of my disorderly narrative, and try to cast a broad perspective over the entire inventory of 87 + 52 = 139 samples of tiny snails stacked at the end of my lab bench this afternoon, and all six essays I have posted on this subject thus far, 2006 - 2026 [6].  There has been an endemic radiation of Fontigentid gastropods in The Great Valley of Virginia.  And several generations of malacologists, including my own, have been Humpfing around the edges of it for years, like sour kangaroos.  

Sure, I’d be pleased to find a collaborator to sequence a couple genes on a few snails and help me with the descriptions of Fontigens malabadi and F. orndorffi, no matter how small.  But what we really need is a PI to write a big grant proposal to take all 139 little vials off the end of my lab bench and see if we can work out the fascinating history of the entire evolutionary radiation.

Because the joint distribution of these 12+ enigmatic little creatures is a codex of the Appalachian orogeny.  Exactly like the pleurocerid snails, their distributions are older – much older – than the drainage basins in which they live.  Populations of Fontigens do not give a rat’s rear end whether their cave stream is running toward the Atlantic, the Ohio, or the Tennessee.  Even modern crow-fly distance means nothing to them.  Let me give you just one example.

The Great Valley of Virginia

Bob Hershler described Holsingeria unthanksensis – certainly the most peculiar element of the fauna – as endemic to Unthanks Cave in Lee County, draining toward the Tennessee River way down in the SW tip of Virginia [2].  Since 1989, Holsingeria populations have been discovered in four other Lee County caves (Spangler, Tater, Burial, and Gibson #1).  Then in 2003, Hershler and colleagues documented a highly disjunct population of Holsingeria in Skyline Caverns, way up north in Warren County, draining through the Shenandoah River to the Atlantic [7].  And no populations of Holsingeria have ever been discovered in the 500 linear kilometers between Lee and Warren County whatsoever.

Now here in the present essay I have described a new species, Fontigens orndorffi, with exactly that same bizarre distribution.  Fontigens orndorffi co-occurs with Holsingeria in Spangler Cave, way down in Lee County, as well as in Kinzer Hollow Cave, a few km E of Spangler.  And F. orndorffi is also found in Warren County, in Rogers Belmont Cave just a couple km W of Skyline Caverns.  And no populations of F. orndorffi are known in the 500 km between Lee and Warren Counties, either.

That is not a coincidence.  These tiny snails are trying to tell us something big about the ancient history of the Southern Appalachians.  If you hear that Yopp as clearly as I do, and you want to help, apply within.

Notes:

[1] Hershler, R., J.R. Holsinger & L. Hubricht (1990) A revision of the North American freshwater snail genus Fontigens (Prosobranchia: Hydrobiidae). Smithsonian Contributions to Zoology 509: 1-49.  For a review and an appreciation, see:

• Springsnails of the Blue Ridge [26July06]
• My Buddy Bob [6July22]

[2] Hershler, R. H. (1989) Holsingeria unthanksensis, a new genus and species of aquatic cavesnail from eastern North America. Malac. Rev. 21: 93-100.  For more, see:

• Cave Snail Adventure [22Aug07]

[3] Actually one sample from 1987 and one from 2008.  But the rest from 2013 – 2019.

[4] Dillon, R.T., Jr., T.E. Malabad, W.D. Orndorff & H-P. Liu (2023) Three new Fontigens (Caenogastropoda: Fontigentidae) from caves in the Appalachian Ridge and Valley Province, Virginia. Pp. 283 - 306 in Dillon, R.T., Jr. et al. The Freshwater Gastropods of North America Volume V: Ohio, Cumberland, and Tennessee River Systems. FWGNA Press, Charleston. [pdf]  For a review, see:

• Three New Fontigens from Virginia [9Jan24]

[5] This is just the second population of F. hersheri ever discovered: Litton Cave #1, Lee County.

[6] In addition to my essays of 26July06, 22Aug07 and 9Jan24 linked above, one must count last month's essay (12Feb26), this month's essay (5Mar26) and my review of the 2021 molecular study published by Liu, Schroeder, Berry, and Dillon [pdf]:

• Startled by Fontigens, sort-of, I suppose [9Aug22]

[7] Hershler, R. H., H-P. Liu & F. G. Thompson (2003) Phylogenetic relationships of North American nymphophiline gastropods based on mitochondrial DNA sequences. Zoologica Scripta 32: 357-366.

An endemic radiation, no matter how small

Wanted: Collaborator.  Cranky old malacologist in the twilight of his dubious career seeks bright young evolutionary scientist with working laboratory and good molecular skills.  Collaboration to explore a previously unappreciated endemic radiation of hydrobioid freshwater gastropods, with potential to yield insights into the tectonic history of North America.  Apply within.

I was born a child of the American Family Road Trip.  My earliest memories of the wide world around me came from the rear-facing jump seat of a red 1959 Chevy station wagon [1], riding south up old US-11 toward Grandma’s house.  And vividly I remember billboards advertising the show caves – Grand Caverns, Skyline Caverns, Endless Caverns, and the crown jewel, Luray.  Hear Rocks Sing? Wonderful.

The Great Valley, with Show Caves [2]

We travelled up and down The Great Valley of Virginia.  Dad liked to hit the road before the crack of dawn, so we’d begin our day in the Shenandoah drainage, all those pretty little rivers under all those picturesque little bridges flowing north down to the Potomac.  But soon we’d crest a low rise and enter the James River drainage – the “Beautiful James,” Dad called it – running east toward Richmond.  Another 30 – 40 minutes up US-11 we’d crest another almost-imperceptible rise and enter the Roanoke Drainage, flowing SE toward North Carolina.  Then up a long grade to the New River Valley – a high plateau, actually – flowing mysteriously west toward the Ohio.  And then finally, imperceptibly, we’d enter the headwaters of the Tennessee River, flowing south.  That’s five very different river systems, each with distinctive biotic elements, flowing to all five points of the compass, draining from The Great Valley of Virginia.

And although the geology over which we traveled was complicated, the predominant bedrock has been, for quite a few years now, Paleozoic limestone.  And the hills are honeycombed with caves.  For every big show cave my family visited, there are a thousand caves that tourists cannot [3].

Indeed, my childhood friends and I were familiar with one closed-off cave at the City of Waynesboro’s Coyner Springs Park, where the Dillon family cooked out many a hot summer’s evening.  And I probably wasn’t much more than six years old when I first held in my tiny hand an even tinier hydrobioid snail of the genus Fontigens.  Those little snails covered the watercress like pepper in Coyner Springs run, the city’s water supply, where all the kids invited to everybody’s birthday party splashed barefoot through the ice-cold, crystal-clear waters.

Tom Malabad at Big Entrance Crawl Cave, Scott Co.

I couldn’t identify those bazillions of teensy little black snails, any more than I could identify any of the other familiar freshwater gastropods of my youth.  My readership of long tenure will be well-acquainted with my childhood frustrations in that regard, and how such frustrations ultimately framed my entire professional career [4].  In fact, I still couldn’t identify the population of hydrobioid gastropods grazing across the water cress at Coyner Springs Park as late as 1979, when I carried a ball jar full of them to my fellow graduate student Bob Hershler, laboring at the bench beside me at the Academy of Natural Sciences in Philadelphia.

Bob scratched that particular itch in 1990, with his admirable “Revision of the North American Freshwater Snail Genus Fontigens,” published together with legendary cave biologist John Holsinger and legendary malacologist Leslie Hubricht [5].  In addition to my childhood playmate Fontigens nickliniana, Bob and his team recognized four other species in The Great Valley, the widespread F. orolibas and three with more restricted ranges: F. bottimeri, F. morrisoni, and F. tartarea [6].  Bob listed a sixth species, Fontigens turritella, from just over the mountains in adjacent West Virginia.

Although all six of those species can be found in subterranean waters, the first four were described from above-ground springs, F. tartarea and F. turritella apparently the only obligate cave-dwellers.  And by 1989, Bob had described a seventh obligate cave-dwelling hydrobioid from The Great Valley very closely related to Fontigens [7], Holsingeria unthanksensis [8].

From Hershler [4,7]

Bob Hershler ranked among the best malacologists of our generation, and I was pleased to watch from the sidelines as he worked his way through the North American hydrobioids, not just the Fontigens of the Great Valley, but all of the hydrobioid snails all across this great wide continent 1985 - 2017.  But then, he disappeared [9].  And the snails did not.

At this point I must beg your indulgence for a flashback, to the era of the Second Great Environmental Awakening [10].  In 1979, the Commonwealth of Virginia joined a growing list of states [11] with special laws on the books directed toward cave protection.  No other state in the union, however, could boast at that time, nor can boast today, of a dedicated Karst Protection Program, staffed by biologists specifically charged with the inventory and protection of subterranean fauna associated with caves, karst and other groundwater environments, including springs.  My good buddy Wil Orndorff was hired as Karst Protection Coordinator for the Commonwealth of Virginia in 2001.

Will Orndorff

I first met Wil on the “Cave Snail Adventure” I described in the columns of this blog back in 2007 [22Aug07], leading a hunt for Holsingeria in Unthanks Cave, way down in the SW tip of the state.  Back in those days, the emphasis of Wil’s program was on karst groundwater protection, primarily funded by an EPA Clean Water Act grant.  They subsequently went through what Wil describes as “very lean years” during which time their funding was primarily from studies of the White Nose Syndrome of bats.  But the funding situation improved in 2013, at which point the team initiated a systematic inventory of the biota of Virginia caves and karst environments in earnest.  Tom Malabad joined the full-time karst team staff in 2016.

So in November of 2018, about a year after Bob Hershler had retired, I was pleasantly surprised to receive an email from Wil, with Tom on the CC line.  The subject line read, “Some Virginia cave and spring snail collections that need you.”

The tale of those N = 61 Virginia-collections-that-needed-me was told in my essay of [9Jan24], posted on this blog just a bit over two years ago.  The collection dates on the meticulously-documented labels they bore were almost entirely 2013 – 2018 [12].  My loyal readership might remember that, setting aside the subset containing only land snails and the subset containing only freshwater gastropods typical of above-ground habitats, I was left with a still-remarkable 20 samples of tiny hydrobioid snails on my bench.

Tom Malabad

That first batch of 20 included 11 populations of F. orolibas, 3 of F. bottimeri, 2 of F. morrisoni [13], 2 of Holsingeria, and two populations of Fontigens bearing shells unlike anything I had ever seen before.  So I got back in touch with Wil and Tom, and they sent me a second batch of 16 samples in September of 2019, and a third batch of 10 samples in February of 2020.  And in that February batch, I found what looked like a third undescribed species of Fontigens.  Oh, for Heaven’s sake.

I hate describing new species, and simply do not have the wherewithal to do so.  I have been retired for ten years now, working off plywood benches laid across milk crates in my son’s old bedroom.  It is irresponsible in this day and age to describe new species without genetic data to confirm, and that chapter in the book of my long and checkered career has long turned.

 

But by the Blessings of Divine Providence, completely independent of all the Fontigens my buddies Wil and Tom were sending me from the Great Valley of Virginia, I was also involved at that time in a separate project on Fontigens cryptica in Kentucky [14].  And my Kentucky collaborators and I had found some funding.  And I had interested our good friend Hsiu-Ping Liu out in Colorado to do the genetic work.  And we were able to piggy-back the Virginia Fontigens work on the Kentucky Fontigens funding.

 

The upshot of all this churn was that in late 2023 the team of Dillon, Malabad, Orndorff and Liu described three new cave-dwelling Fontigens from The Great Valley of Virginia: Fontigens hershleri, F. benfieldi, and F. davisi [15].  That brought the total number of teensy-little phreatic hydrobioid species under the rolling hills and gentle mountains that disappeared into the blue haze behind my dad’s 1959 Chevy Station Wagon up to 7 + 3 = 10.

From Dillon et al. 2023 [13]

One would think that would be enough, am I right?  Surely those 61 + 16 +10 = 87 samples that Wil and Tom had sent me by early 2020 would pretty much scour all the tiny little ghostly-white gastropods out of all the caves, springs and seeps in the entire Commonwealth of Virginia, yes?  And perhaps our good buddies might turn their attention to the 99.99999% of the waters of the Old Dominion a bit easier to sample?  One would be wrong.  Stay tuned.

 

Notes:

 

[1] My mother named that car "Red Wing," after one of her favorite ballads.  She loved to sing that song!  The whole Dillon family did.

[2] Key to the Show Caves of The Great Valley: (A) Crystal, (B) Dixie, (C) Endless, (D) Gap, (E) Grand, (F) Luray, (G) Natural Bridge, (H) Shenandoah, (I) Skyline.

 

[3] Here’s a verbatim quote from Wil Orndorff: “Conservatively, as of today approximately 3,500 known caves in Virginia meet the international definition of a minimum length of 5 meters, with 368 of them designated as significant under the Virginia Cave Protection Act.”

 

[4] For more on the frustrations of my nerdy youth, see:

• The Clean Water Act at 40 [7Jan13]
• To Identify a Physa, 1971 [8Apr14]

[5] Hershler, R., J.R. Holsinger & L. Hubricht (1990) A revision of the North American freshwater snail genus Fontigens (Prosobranchia: Hydrobiidae). Smithsonian Contributions to Zoology 509: 1-49.

 

[6] As of 1990, Hershler et al considered F. tartarea restricted to West Virginia.  A population of the species was not discovered in a Virginia cave until 1994.

 

[7] Technically Bob assigned Holsingeria to the Lithoglyphinae (later Lithoglyphidae) on the basis of penial morphology.  But it’s a Fontigens.  Just look at it, for heaven sake, and use your biological intuition.

 

[8] Hershler, R. H. (1989) Holsingeria unthanksensis, a new genus and species of aquatic cavesnail from eastern North America. Malac. Rev. 21: 93-100.

 

[9] For an appreciation of the career of Dr. Robert Hershler, see:

• My Buddy Bob [6July22].

[10] I would date the “First Great Environmental Awakening” from the creation of Yellowstone National Park in 1872 to approximately 1916, the creation of the National Park Service.

 

[11] Off the top of his head, Wil could think of eight states with cave protection laws: Virginia, West Virginia, Kentucky, Tennessee, Georgia, Arkansas, Missouri, and Pennsylvania.

 

[12] One collection date was 1987, one was 2008.

 

[13] One of those morrisoni was misidentified.  The correct identification was F. tartarea.  I didn’t catch my error until earlier this year, in fresh samples collected by the team 2020 -2025.  More about which next month.

 

[14] The story of the rediscovery of Fontigens cryptica was a fascinating one, which I serialized over a stretch of five years:

• Lori Schroeder’s tiny snails [17July17]
• The most cryptic freshwater gastropod in the world [6Aug17]
• Not finding Fontigens cryptica [6Sept17]
• Finding Fontigens cryptica [3July19]
• Startled by Fontigens, sort-of, I suppose [9Aug22]

[15] Dillon, R.T., Jr., T.E. Malabad, W.D. Orndorff & H-P. Liu (2023) Three new Fontigens (Caenogastropoda: Fontigentidae) from caves in the Appalachian Ridge and Valley Province, Virginia. Pp. 283 - 306 in Dillon, R.T., Jr. et al. The Freshwater Gastropods of North America Volume V: Ohio, Cumberland, and Tennessee River Systems. FWGNA Press, Charleston.  For a review, see:

• Three New Fontigens from Virginia [9Jan24]