Dr. Rob Dillon, Coordinator

Tuesday, April 9, 2024

The Freshwater Gastropods of The Great Plains

We are pleased to announce a major expansion of the FWGNA Project, now extending our coverage westward to include the prairie states of Kansas, Nebraska, South Dakota, and North Dakota.  The Freshwater Gastropods of the Great Plains, by Bruce J. Stephen, Robert T. Dillon, Jr, and Martin Kohl is now online and available for reference!  Check it out:

Visit the FWGGP

In this important new web resource, we report the results of an original survey of 795 rivers, streams, lakes, and ponds across a big slice of the American heartland, documenting 33 gastropod species.  For each species we provide range maps and ecological notes, with a photo gallery and a dichotomous key for easy identification.

Although in areal extent our 308,000 square mile Great Plains study area is the largest of the eight regions thus far covered by the FWGNA Project, by freshwater gastropod species richness it is the smallest.  We suggest two historical factors to account for the relative poverty of the Great Plains malacofauna: the absence of landform diversity, and the absence of time sufficient for a regionally adapted fauna to evolve.  The effects of Pleistocene glaciation, if any, seem to have been to increase species richness.  State subtotals were 16 species in Kansas, 18 in Nebraska, 19 in South Dakota, and 23 in North Dakota.

We also document reductions in species richness for three of the four Great Plains states when compared to expectation from the published literature.  Kansas seems to have lost 4 species, South Dakota 6 and Nebraska 14.  The freshwater gastropod species apparently missing from each state typically become more common further north.  Although some of this phenomenon is certainly due to sampling error, we think it likely that climate change may have been a factor in the decreased species richness of The Great Plains.

Tuesday, March 12, 2024

Lymnaea (Galba) cockerelli, Number 15.

Bengt Hubendick [1] recognized 13 valid species of lymnaeid snails in North America [2], setting aside the patelliform genus Lanx, which he did not treat.  To that tally should be added L. auricularia, introduced to this continent more recently, and L. caperata, which Hubendick mistakenly synonymized under L. humilis.  Oh, and subtract emarginata from Hubendick’s list, a junior synonym of L. catascopium.  Is that the complete continental fauna?  To Hubendick’s canonical list of 13 + 2 – 1 = 14 species of Lymnaea inhabiting the waters of North America, might be added a Number 15?

Yes.  Last month [13Feb24] we reviewed the long and tortured history of Isaac Lea’s [3] nomen Lymnaea bulimoides, recognized as distinct by Hubendick but much confused by many other authorities with another of Hubendick’s canonical species, Lymnaea cubensis.  We reproduced images of 23 shells in that overly long essay.  I have subtracted the twelve images of L. cubensis/viator and other miscellaneous lymnaeids and re-reproduced the remaining eleven images as thumbnails in a single montage below, adding five images of related taxa I mentioned in passing last month but didn’t figure.

See footnote [4] for complete caption.

Does that set of thumbnail figures look homogeneous to you?  Or, just on the basis of those 16 shell images, knowing nothing about the biology of the snails that bore them, could you divide the set above into two distinct subsets?  Let’s back up 118 years and get a fresh start at that question.

It will be remembered from last month’s essay that in 1906 Henry Pilsbry and James Ferriss [8] recognized four subspecies of Lymnaea bulimoides.  The typical form, originally described from the Oregon Territory in 1841, is depicted in thumbnails A, B, C, K, and M.  The (essentially indistinguishable) techella form, described from Texas in 1867, is depicted in thumbnails D, E, I, and O.  To these Pilsbry and Ferriss added a sonomaensis form (G, P) from California, and their own brand new cockerelli (F, J, L, N), from New Mexico, Colorado, Nebraska and South Dakota.  Quoting Pilsbry verbatim:

“This form (cockerelli) differs from L. bulimoides and L. techella by its more globose shape and shorter spire, and so far as we have seen is readily separable from both.”

In 1909 Pilsbry’s disciple, Frank Collins Baker [13], raised sonomaensis to the full species level and described a new Lymnaea hendersoni from Colorado, “at first thought to be sonomaensis” but “differing in the form of the spire and aperture.”  And in 1911 Baker [14] published his landmark monograph on the “Lymnaeidae of North America, Recent and Fossil,” cataloging and reviewing 103 species and subspecies in 15 genera, subgenera, and groups [15], including all five of the lymnaeid taxa listed above in exhaustive detail.

The figure below is a concatenation of Baker’s [16] plate XXVII (figs 20 – 35) and plate XXVIII (figs 1 – 19).  Figures 20 – 29 are Galba bulimoides (ss), figure 25 being the holotype, the same shell as figure A above.  Baker identified figures 1 – 3, 8, and 30 – 35 as Galba bulimoides techella, figures 4 -  7 as G. bulimoides cockerelli, figures 9 – 11 as a new form G. bulimoides cassi, figs 12 – 14 as G. sonomaensis, figs 15 – 18 as his G. hendersoni, and fig 19 as Galba perpolita, more about which anon.

To my eye, this montage of 35 shells is as naturally and easily divisible into two sets as the montage of 16 thumbnails that opened this essay.  I distinguish a set that looks like the bulimoides holotype (#25), which includes all those Baker identified as techella and cassi, and a subset with a much larger, more inflated body whorl, identified by Baker as cockerelli, sonomaensis, hendersoni, and perpolita.

Focus with me now on figs 4 – 7, depicting G. bulimoides cockerelli (three populations), and try to compare that subset of four shells with all the other (N = 23) images of shells borne by all the other subspecies of bulimoides: 1 – 3, 8 – 11, 20 – 35.  I know that’s a challenge, but humor me, OK?  Those two subsets clearly belong to different sets, can you see what I am saying?  Why in the world would splitters as practiced in their art as Pilsbry and Baker identify the snails bearing all 27 of those shells as a single species?  Especially when they split out figs 12 – 14 as a separate species sonomaensis?  And figs 15 – 18 as a separate species hendersoni?

Baker [14] plates 27, 28.  See [16] for scale.

The answer lies in the subset of five shells boxed in red.  This is a sample collected from the rural community of Bardsdale in Ventura County, CA, that weighed heavily in Baker’s calculations.  He wrote, in the “Remarks” section of his treatment of cockerelli, that  “Specimens from Ventura County, California, show a tendency to vary toward the techella form of shell, clearly showing that the cockerelli race is an offshoot of techella.”  That sentence is phrased as though he wanted to identify the entire Bardsdale population as cockerelli, but when the time came to his assemble plates, Baker split five specimens from Bardsdale three-and-two.

Well, dang my hide.  I reckon if there’s any splittin’ to be done around these parts, Sheriff Dwight Taylor is the man for the job.  In 1960 Taylor teamed up with vertebrate paleontologist Claude W. Hibbard on a 223-page monograph [17] of “two late Pleistocene faunas from southwestern Kansas.”  Hibbard & Taylor identified nine species of lymnaeids in the prehistoric fauna of the Great Plains, including Lymnaea stagnalis, six nominal species of Stagnicola, and two nominal species of Fossaria.  And as they sorted out the Stagnicola [18], Hibbard and Taylor observed, “from a review of previous literature and on examination of specimens it appears that Stagnicola bulimoides cockerelli is specifically distinct from S. bulimoides and S. bulimoides techella.”

Taylor further observed that the geographic ranges of bulimoides and cockerelli are different (although overlapping), cockerelli being the only species to extend through the northern Great Plains, and that the “apparent lack of intergradation” where bulimoides and cockerelli do overlap (in the Southwest, for example) might be viewed with special significance.  Here the young Dwight W. Taylor of 1960 seems almost to flirt with the biological species concept [19].  Taylor went on to re-identify the red-box population of cockerelli that Baker figured from Bardsdale as bulimoides techella in its entirety, and to synonymize Baker’s (1911) hendersoni under cockerelli.

And in 1973, Joe Bequaert  & Walter Miller brought Taylor’s point home [20].  In their landmark “Mollusks of the Arid Southwest with an Arizona Check list,” Bequaert & Miller relayed the following report:

“R. H. Russell informs us that he found in 1969 thriving colonies of S. b. techella and S. cockerelli living together (sympatric) in the same pond at two stations in Navajo Co. (O’Haco Farm and Sitting Bull Trading Post), without transitional specimens or other evidence of interbreeding in nature.”

And indeed.  Returning a second time to F. C. Baker’s red-box sample from Bardsdale.  I do not agree with Taylor that the snails bearing all five of the shells boxed in red above are best identified as L. bulimoides techella.  To my eye, it appears that Baker’s original identifications distinguished two distinct biological species: Figs 6 and 7 L. cockerelli and Figs. 33 – 35 L. bulimoides.  The Bardsdale collection appears to have been made from a site where a pair of reproductively isolated species co-occur, just as in Arizona.

In conclusion.  Lymnaea cockerelli Pilsbry and Ferriss 1906 is a distinct and valid biological species, reproductively isolated from L. bulimoides Lea 1841 and all 13 other North American species of lymnaeids.  Junior synonyms of L. cockerelli include sonomaensis Hemphill 1906 and hendersoni Baker 1909.  Lymnaea perpolita Dall 1905 may be a senior synonym.

Yes, dang my hide, again.  Look back with me at Figure 19 on the plate of shells I concatenated from Baker [14] above.  That is an image that Baker borrowed from William Healy Dall’s 1905 monograph on the land and freshwater mollusks collected by the 1899 Harriman Expedition to Alaska [21].  On his pages 78 – 79 Dall described a single “small, translucent, dark amber color” shell collected at Nushagak, Bristol Bay, Alaska as Lymnaea (Stagnicola?) perpolita n. sp.  It really looks to me like Dall may have scooped Pilsbry and Ferriss by one year.

But as far as I can tell, Dall’s nomen perpolita has almost never [22] been applied to any other population of snails ever collected again, while Pilsbry and Ferriss’ cockerelli has seen wide use throughout western North America.  Forget that you read these last two paragraphs.  I never wrote them.

So to summarize, over last month’s essay and this month’s as well.  Isaac Lea’s (1841) nomen Lymnaea bulimoides has been applied to populations of at least three distinct biological species, including cubensis/viator and cockerelli as well to as to the bona fide bulimoides of “Oregon” as originally described.  The eastern extent of the L. bulimoides range has been overstated.  My buddy Bruce Stephen and I have not been able to confirm populations of bona fide L. bulimoides anywhere in Kansas, Nebraska, or The Dakotas.  Populations of both L. cubensis/viator and L. cockerelli are not uncommon in those states, however.

Then opening the Burch Bible [12] to pages 172 – 174 we find five (full) species listed under Fossaria (Bakerilymnaea), the subgenus set aside for crappy little amphibious lymnaeids with bicuspid first laterals.  Under the first of those species, Fossaria (Bakerilymnaea) bulimoides, we find six subspecies.  In the table above I have listed those 12 taxa together with our modern FWGNA understanding of their identities.  For the time being.  Additional data would be most welcome.


[1] Hubendick, B. (1951)  Recent Lymnaeidae.  Their variation, morphology, taxonomy, nomenclature and distribution.  Kungliga Svenska Vetenskapsakademiens Handlingar Fjarde Serien 3: 1 - 223.

[2] Hubendick listed three species as Holarctic: stagnalis, truncatula, and “palustris,” by which he was referring to populations better identified as elodes here.  As unique to North America, he listed ten: humilis, cubensis, bulimoides, catascopium, emarginata, columella, megasoma, haldemani, arctica and “utahensis (?)”  I would add a second question mark behind utahensis.  In fact, I’m not 100% sold on haldemani.

[3] Lea, Isaac (1841) On fresh water and land shells (continued).  Proceedings of the American Philosophical Society 2(17): 30 – 34.

[4] Original identification and authority for the 16 shells depicted, with standard length if it is known or can be estimated:  (A) Lea’s bulimoides holotype 9.3 mm, (B) bulimoides from Haldeman [5], (C) bulimoides from Binney [6], (D) techella from Haldeman [7], (E) techella from Pilsbry [8] 13.0 mm, (F) cockerelli from Pilsbry [8] 10.0 mm, (G) sonomaensis from Pilsbry [8] 10.0 mm, (H) vancouverensis from Baker [9] 18.5 mm, (I) techella from Clarke [10] 10.6 mm, (J) cockerelli from Clarke [10] 5.5 mm, (K) bulimoides from Clarke [10] 12.0 mm, (L) cockerelli from Leonard [11], (M) bulimoides from Burch [12] 13.8 mm, (N) cockerelli from Burch [12] 13.8 mm, (O) techella from Burch [13] 13.1 mm, (P) sonomaensis from Burch [12] 6.9 mm.

[5] Haldeman, S.S. (1844) A monograph of the freshwater univalve Mollusca of the United States, Number 7  Philadelphia: Cary & Hart, Dobson, and Pennington. 32 pp, 4 plates.

[6] Binney, W.G. (1865) Land and fresh water shells of North America Part II, Pulmonata Limnophila and Thalassophila. Smithsonian Miscellaneous Collections 143: 1 – 161.

[7] Haldeman, S.S. 1867  Description of a new species of Limnaea.  American Journal of Conchology 3: 194.

[8] Pilsbry, H.A. and J.H. Ferriss (1906)  Mollusca of the southwestern states II.  Proceedings of the Academy of Natural Sciences of Philadelphia 58: 123 – 175.

[9] F. C. Baker’s brief (1939) description of Stagnicola bulimoides vancouverensis nov. var. was published in The Nautilus 52(4): 144.  The figure reproduced above followed in Nautilus 53(1) plate 7.

[10] Clarke, A. (1973) The freshwater molluscs of the Canadian Interior Basin. Malacologia, 13, 1-509.

[11] Leonard, A.B. (1959) Handbook of Gastropods in Kansas. Miscellaneous Publications of the University of Kansas Museum of Natural History 20: 1 – 224.

[12] 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 that agency in 1982.  It was also serially published in the journal Walkerana (1980, 1982, 1988) and finally as stand-alone volume in 1989 (Malacological Publications, Hamburg, MI).

[13] Baker, F.C. (1909) A new species of Lymnaea.  The Nautilus 22: 140 – 141.

[14] Baker, F.C. (1911) The Lymnaeidae of North and Middle America, Recent and Fossil.  Chicago Academy of Sciences, Special Publication Number 3.  539 pp.

[15] Note that the number of genera, subgenera, and other higher-level "groups" recognized by Baker in the North American Lymnaeidae is exactly the number of valid biological species.  This is not a coincidence.

[16] Quoting the caption to Plate XXVII, Figs 20 – 35 were “enlarged about two diameters” at their reproduction, and on that basis I have added the red scale bar.  Figs 1 – 19 were mostly “enlarged 2 diameters” on their original plate XXVIII, with the exceptions of figs 12 – 14 “enlarged about three diameters,” and fig 19, “1.5 diameters.”

[17] Hibbard, C.W. and D.W. Taylor (1960) Two late Pleistocene faunas from southwestern Kansas.  Contributions from the Museum of Paleontology, University of Michigan 16(1): 1 – 223.

[18]  Yes, Dwight Taylor considered L. bulimoides to be a little Stagnicola, not a big Galba/Fossaria.  F.C. Baker made exactly the same judgement call in 1939, see footnote #17 of last month’s essay.  This is yet further support, if any is needed, for Hubendick’s [1] opinion that there is insufficient morphological basis for the recognition of genera within the family Lymnaeidae.  The FWGNA follows Hubendick in assigning all North American lymnaeids (except the patelliform genus Lanx) to the typical genus Lymnaea, adding (subgenera) for their indexing function alone.  We do not assign Lea’s bulimoides to Lymnaea (Galba) to transmit any hypothesis of evolutionary relationship whatsoever, but only because “Galba” seems to connect with the greatest fraction of the recent literature.

[19] I never met the reclusive millionaire Dwight Taylor, but the dark shadow he cast over freshwater and terrestrial malacology extended far beyond the American West.  Well, even a sundial facing west will be right once a day.

[20] Bequaert, J. & W. Miller (1973) The Mollusks of the Arid Southwest, with an Arizona Check List.  Tucson: University of Arizona Press.  

[21] Dall, W. H. (1905)  Land and fresh water mollusks of Alaska and adjoining regions.  Smithsonian Institution Harriman Alaska Series 13: 1 – 171.

[22] My search of the iDigBio database [23] for family = Lymnaeidae and species = perpolita returned 12 hits in the USNM from Alaska and two hits in the University of Alaska Museum from Iceland.  Very little data on any of the 14 – not even dates of collection for the USNM records.

[23] For more about iDigBio, see:

  • 20 Years of Progress in the Museums [22May19]

Tuesday, February 13, 2024

What is Lymnaea bulimoides?

Thomas Nuttall (1786 – 1859) was a pioneering naturalist on the American frontier, most famous as a botanist but with interests in geology, ornithology, and yes, malacology as well.  In 1834 he resigned his professorship at Harvard and joined an expedition up the newly-opening [1] Oregon Trail.  Nuttall spent most of the next two years in the Pacific Northwest, interrupted by an exursion to Hawaii, returning to a position at the Academy of Natural Sciences of Philadelphia in 1836.

In 1841 our old buddy Isaac Lea [2] published a brief, Latinate description of Lymnaea bulimoides [3], which he followed with an English translation in 1844, as follows [4]:

"Shell ovately conical, rather thin, smooth, shining, diaphanous, brownish yellow, slightly perforate; spire rather short; sutures small; whorls five, slightly convex; aperture ovate. Hab. Oregon, Prof. Nuttall."

Alas, Lea never published a figure of his Lymnaea bulimoides.  And the “Oregon” from which Prof. Nuttall had just fetched that first sample was a vast territory that included all of the modern states of Washington and Idaho, parts of Montana and Wyoming and most of British Columbia [5].

By the blessings of Divine Providence, however, Lea’s type lot has been preserved, even unto the present day.  Both Haldeman [6] and Binney [7] published little 1:1 figures of “authentic specimens,” as reproduced below.  Prof. Haldeman [8] added a very similar looking Limnea techella from Texas to the literature in 1867 as “surface smoother than in L. bulimoides, of Oregon, with the lines of accretion less apparent, and the labium more angular.”  His little 1:1 figure of L. techella is also reproduced below.

Hald. [6] Binney [7] Hald. [8]

Now I feel quite confident that a significant fraction of my (admittedly rather specialized) readership will be at least passingly familiar with the crappy little lymnaeids we find crawling around on the muddy margins of our rivers, ditches, and ponds here in the American East.  You all listen up.  None of you would ever confuse a population of lymnaeids bearing shells such as those depicted above with Lymnaea (Galba) cubensis/viator, am I right?  The body whorl is way too big.  And – good grief – look at the scale bar on that holotype!  Adult L. bulimoides often reach double-digit shell lengths, whereas none of our crappy little Galba-type lymnaeids on this side of the Mississippi River ever really do.

Nevertheless, in 1891 Henry Pilsbry became the first in a long line of professional malacologists to confuse L. bulimoides with L. cubensis, in a survey of the malacofauna of the Yucatan peninsula [9].  He began by synonymizing L. umbilicata C.B. Adams 1840 under L. cubensis Pfeiffer 1839.  Then he wrote:

"The typical cubensis ranges at least as far west as the Mississippi River and eastern Texas.  West and southwest of this it gives place to L. techella Hald., and L. bulimoides Lea.  The last form may be considered a geographic race or subspecies of the cubensisL. techella Hald. is nearly identical with umbilicata."

Pilsbry corrected himself, however, in a survey of the Mollusca of the southwestern states he published with J. H. Ferriss in 1906 [10]:

Lymnaea techella was formerly considered by one of us to be a synonym or race of L. cubensis Pfr, and L. bulimoides was treated as a variety of the same species.  They are certainly very similar, but cubensis has a more triangular and less broadly developed columellar expansion.”

Then going beyond a simple resurrection of Isaac Lea’s L. bulimoides, Pilsbry and Ferriss went on to recognize three subspecies underneath it: Haldeman’s techella from Texas, New Mexico and Arizona, Hemphill’s sonomaensis from California, and their own new cockerelli, widespread in New Mexico, Colorado, Nebraska and South Dakota.

Everybody look with me now at the three Pilsbry & Ferriss figures I have reproduced below.  They’re all significantly larger than our crappy amphibious lymnaeids here in The East, right?  The shell lengths reported by Pilsbry for all (N = 16) specimens he measured of all subspecies ranged from 8 mm up to a whopping 14 mm, with mean = 10.2 mm, good grief!  Very, very clearly not L. cubensis.

From Pilsbry & Ferriss [10]

Pilsbry’s 1906 dabbling with the obscure little lymnaeids of the American West did not take place in isolation, of course.  Indeed, the flood of pulmonate gastropod descriptions that washed across North America in the mid-nineteenth century became a torrent in the early twentieth, our hero Frank Collins Baker surfing high upon its crest.  In 1909, Baker [11] raised Hemphill’s sonomaensis to the full species level and described Lymnaea hendersoni from Colorado, a new species “at first thought to be Lymnaea sonomaensis,” but “differing in the form of the spire and aperture.”

And in 1911 he published his landmark “Lymnaeidae of North America, Recent and Fossil [12],” placing his own contributions, and those of his mentor Pilsbry [13], into a continental framework.  Baker recognized four subspecies of Galba bulimoides: the typical form restricted to the West Coast (BC, WA, OR, CA), Haldeman’s techella ranging from California through the desert southwest to Texas, Oklahoma, and Kansas, and Pilsbry’s cockerelli overlapping both, while extending further north into Nebraska and The Dakotas.  To these he added a new subspecies L. bulimoides cassi from California, utterly indistinguishable from techella in all respects, as well as the full species sonomaensis and hendersoni, both indistinguishable from cockerelli.

Although Baker carefully noted radula morphology when any observations were available to him throughout his 1911 monograph, he did not begin to draw a distinction between species bearing bicuspid first laterals and tricuspid first laterals until 1928 [14].  He did note that the radula of G. bulimoides cockerelli bore bicuspid first lateral teeth, “similar to that of cubensis” in 1911, and that hendersoni also bore bicuspid first laterals “similar to those of techella,” but offered no observations on any of the other taxa mentioned above, including (oddly) techella.

There is no evidence that F.C. Baker ever confused L. bulimoides, or any of the bulimoides-related taxa, with L. cubensis, or any cubensis-related taxa, at any point in his illustrious career.  He was keenly alert to even the finest distinctions in phenotype, and ever ready to recognize new species and subspecies on that basis.  In 1919 he described a Galba alberta from western Canada, to my eye looking like a dwarfed elodes, with bicuspid first laterals [15].  In 1929 he teamed up with Junius Henderson to describe a Fossaria perplexa from Washington state [16].  And in 1939 he added a fresh subspecies Stagnicola [17] bulimoides vancouverensis, distinguishing a strikingly large-bodied population from British Columbia [18].

From Leonard [19] Plate 1

In 1959 A. Byron Leonard published a thorough and influential review of the entire gastropod fauna of Kansas [19].  And I feel certain that he must have had a copy of Baker’s 1911 monograph on his desk, showing the range of both G. bulimoides techella and G. bulimoides cockerelli extending through the Jayhawk State.  In fact, Baker listed five localities for techella in Kansas, although none for cockerelli.  Remember that.  Baker also (of course) included Kansas within the ranges of G. humilis and G. obrussa [20], both of which he considered elements of the continental fauna broadly, but did not consider that the range of G. cubensis extended as far north as Kansas.

So, Byron Leonard can be excused for identifying L. bulimoides techella in Kansas, and not identifying L. cubensis.  His Plate 1 is reproduced above, showing what appears to be an unusually large [21] L. cubensis/viator shell identified as “L. bulimoides techella.”   This seems to be a fresh re-emergence of the bulimoides/cubensis confusion independent of Pilsbry’s 1891 error.

A third, independent confusion of bulimoides and cubensis also has its roots in the soil of F.C. Baker but germinated much further north.  Baker provided neither figure nor radular observations for the Fossaria perplexa he described with Junius Henderson from Washington state in 1929 [16].  But his description (“resembles both parva and dalli … larger than dalli and smaller than parva”) strongly suggests a synonym of either L. humilis or L. cubensis/viator.  In 1973, however, Arthur Clarke [22] reported the discovery of a population of crappy little amphibious lymnaeids in Alberta bearing shells “identical with type specimens of F. perplexa” on their backs and radulas with bicuspid first laterals in their mouths.  Since he considered L. cubensis “subtropical and tropical” in its distribution, Clarke reasoned that perplexa must be “a hitherto unrecognized morph of the highly variable Lymnaea bulimoides.”

And if the shell morphology of L. bulimoides is variable enough to include a population that looks like L. perplexa, surely we might also include populations that look like L. alberta, yes?  Clarke did not have any original observations to add in 1973, but on the basis of Baker’s original description of the radula [15], lowered L. alberta to the status of “morph” under L. bulimoides as well [23].

Clarke's [22] "morphs" of L. bulimoides

With the advent of the 1980s came Jack Burch’s “North American Freshwater Snails,” destined to enter the holy canon of American malacology [24].  Burch recognized seven subspecies of Fossaria (Bakerilymnaea) bulimoides: the three of Pilsbry (bulimoides ss, techella, cockerelli), the two added by Clarke (alberta, perplexa), the vancouverensis added by Baker, and Baker’s hendersoni, which had heretofore been considered specifically distinct.  Burch followed Baker in recognizing sonomaensis at the species level, but clean forgot Baker's cassi, no big loss.  Only techella, cockerelli, and the typical subspecies were figured for bulimoides in the Burch Bible, plus sonomaensis as a separate species.

And so it came to pass that in January of 2022 I rendezvoused with our good friend Bruce Stephen in Lawrence, KS, to review the extensive freshwater gastropod holdings of the Kansas Biological Survey 1971 – 1981.  You might remember Bruce from the comprehensive survey of historic freshwater gastropod records from Nebraska [25] he published back in 2015.  Bruce defended his dissertation, a modern survey of freshwater gastropods across Nebraska and South Dakota, in 2018.

Bruce and I spent the week pulling vials of snails out of metal cabinets on the fourth floor of Haworth Hall on the campus of the University of Kansas, ultimately reviewing an impressive 642 lots, identifying 14 samples of Lymnaea humilis, 15 samples of L. cubensis/viator, and zero samples L. bulimoides demonstrating the typical (or “techella”) morphology.  I feel confident that, sitting in these same precincts back in 1959, Byron Leonard [19] confused L. cubensis/viator with L. bulimoides techella.

Indeed, Bruce has never confirmed a population of typical L. bulimoides in Nebraska, or South Dakota, or North Dakota, for that matter.  It would appear that the range of L. bulimoides has been greatly exaggerated, almost certainly by confusion with L. cubensis.

From Bruce's camera 1/22
Bruce and I did confirm 5 lymnaeid populations bearing shells of the cockerelli form in Kansas, with similar populations scattered through Nebraska and The Dakotas as well.  Did F. C. Baker [12] confuse L. bulimoides techella with L. bulimoides cockerelli?  We’ll come back to that question next month.

But returning to the bulimoides/cubensis confusion, and shifting one state south, to Oklahoma.  GenBank holds just two pair of sequences labeled “bulimoides:” a 16S/CO1 pair from E. A. Remigio [26, 27] and a 16S/CO1 pair from Wethington & Lydeard [28].  The former pair (AF485657 and AY227367, respectively), from an individual collected in “Oklahoma” (no further information), are both 99% similar to the big body of sequence data for Galba cubensis/viator that has accumulated in GenBank over many years.

The Remigio sequences were swept up into the 2011 study of Correa et al. [29] and the influential 2021 study of Alda et al. [30], prompting both of those sets of authors, and me myself a sinner [31], to hypothesize that bulimoides might be a junior synonym of cubensis/viator in a pair of posts on this very blog.  Writing here today, I feel quite certain that sequences AF485657 and AY227367 were misidentified at their deposition.  And I have added red-font retractions to the bottoms of my blog posts of [7Aug12] and [6July21].

The pair of 16S/CO1 sequences uploaded by Wethington & Lydeard, EU038315 and EU038362 respectively, are 8.9% and 16.5% different from the Remigio sequences, respectively, and hence did not get swept up into the big worldwide surveys of Correa and Alda.  Blasting them against GenBank, however, both return close matches to sequences obtained from a topotypic population of Lymnaea (Stagnicola) caperata, deposited by Morningstar et al [32]: 98 – 99% for 16S and 96-97% for CO1.  The only conclusion I think it is safe to make at present from the negligible DNA data available for bulimoides is that I am not going any further down this rabbit hole [33].

So let us now set the record straight, for all time.  Lymnaea (Galba) bulimoides is a distinct, valid biological species, not to be confused with Lymnaea (Galba) cubensis/viator.  Fossaria perplexa Baker & Henderson 1929 is not a subspecies, synonym or morph of bulimoides, nor is Galba alberta Baker 1919.

And in conclusion, Brothers and Sisters, I rise to the pulpit.  The confusion and misunderstanding that has historically surrounded the crappy little amphibious lymnaeids of western North America is but an extension of a greater darkness that benights international malacology across five continents, Old World and New.  The figure below is from the 2011 review of neotropical lymnaeids published by Ana Correa and her colleagues [35], as reproduced in my review of [7June21].

From Correa et al. [33]

Populations of crappy little amphibious lymnaeids identified as “Galba cousini (Jousseaume, 1887)” are common and widespread in muddy ditches and ponds on the Pacific side of South America, primarily in Ecuador and Colombia.  Where have you seen snails bearing shells looking like that before?

All the lymnaeid populations we have discussed in this overly long essay, and all of those depicted in Ana Correa’s figure above, are potential hosts for the livestock fluke, Fasciola.  In Central and South America, huge international teams of malacologists and parasitologists have published mountains of research on the evolutionary relationships among truncatula, “schirazensis,” cubensis/viator and – yes – cousini.  A quick search of GenBank returns 35 hits for G. cousini alone.

Meanwhile here in the USA, the richest country on earth, the leader of the free world, we have zero authentic sequences for any population of our own Lymnaea (Galba) bulimoides, known to be an important host of livestock fluke across the Pacific Northwest since 1929 [36].  We have four spurious mtDNA sequences from two crappy snails, both of which I think were misidentified.

United States malacology had a two-generation head start on South American malacology.  Lea (1841) trumps Jousseaume (1887) by 46 years.  I do not know how we have fallen so far behind the rest of the world today, but I do know a continent-scale mess when I see it, and international embarrassment when I feel it.  Malacologists of America, we must do better.


[1] Although pioneered for foot traffic as early as 1811, the Oregon Trail did not become passable by wagon until the 1830s.

[2] For a brief biography of “The Nestor of American Naturalists,” see:

  • Isaac Lea Drives Me Nuts [5Nov19]

[3] Lea, I (1841) On fresh water and land shells (continued).  Proceedings of the American Philosophical Society 2(17): 30 – 34.

[4] Lea, I. (1844/46) Continuation of Mr. Lea’s paper on fresh water and land shells.  Transactions of the American Philosophical Society 9(1): 1 – 31.

[5] The U.S. / Canadian boundary in the Pacific Northwest was not established until 1846.

[6] Haldeman, S.S. (1844) A monograph of the freshwater univalve Mollusca of the United States, Number 7  Philadelphia: Cary & Hart, Dobson, and Pennington. 32 pp, 4 plates.

[7] Binney, W.G. (1865) Land and fresh water shells of North America Part II, Pulmonata Limnophila and Thalassophila. Smithsonian Miscellaneous Collections 143: 1 – 161.

[8] Haldeman, S.S. 1867  Description of a new species of Limnaea.  American Journal of Conchology 3: 194.

[9] Pilsbry, H.A. 1891 Land and Fresh-water mollusks collected in Yucatan and Mexico.  Proceedings of the Academy of Natural Sciences of Philadelphia 43: 310 – 334.

[10] Pilsbry, H.A. and J.H. Ferriss (1906)  Mollusca of the southwestern states II.  Proceedings of the Academy of Natural Sciences of Philadelphia 58: 123 – 175.

[11] Baker, F.C. (1909) A new species of Lymnaea.  The Nautilus 22: 140 – 141.

[12] Baker, F.C. (1911) The Lymnaeidae of North and Middle America, Recent and Fossil.  Chicago Academy of Sciences, Special Publication Number 3.  539 pp.  For a brief biography of our hero, see:

  • The Legacy of Frank Collins Baker [20Nov06]

[13] For an exploration of the relationship between Frank Collins Baker and Emperor Henry Augustus Pilsbry, see:

  • The Emperor, the Non-child, and the Not-short Duct [9Feb21]
  • Dr. Henry A. Pilsbry was a jackass [26Jan21]

[14] Baker, F.C. (1928) Freshwater Mollusca of Wisconsin, Part I, Gastropoda. Bull. Wisc. Geol. Natur. Hist. Survey, no. 70. Madison: University of Wisconsin Press.  Baker proposed Nasonia as a subgenus to distinguish species of Fossaria with bicuspid lateral teeth, but alas, that name was preoccupied.  The German malacologist W. K. Weyrauch proposed the name “Bakerilymnaea” as a substitute in 1964.

[15] Baker, F.C. (1919) Fresh-water mollusca from Colorado and Alberta.  Bulletin of the American Museum of Natural History 41(13): 527 – 539.

[16] Baker, F.C. and J. Henderson (1929) Fossaria perplexa F. C. Baker and Junius Henderson.  Nautilus 42(3): 103-104.

[17] That's right, F. C. Baker himself transferred bulimoides from the genus Galba/Fossaria to the genus Stagnicola, simply because he discovered a population that was unusually large-bodied.  There is absolutely no biological basis for recognizing genus (let alone subgenus) divisions in the worldwide Lymnaeidae.  None.  The FWGNA follows Hubendick in assigning essentially all lymnaeids to a single vanilla genus Lymnaea.  We add subgenera for their indexing function only - just to help the Google machine find our research.  For more, see:

  • The Classification of the Lymnaeidae [28Dec06]  

[18] Baker, F.C. (1939) Stagnicola bulimoides vancouverensis nov. var. The Nautilus 52(4): 144.

[19] Leonard, A.B. (1959) Handbook of Gastropods in Kansas. Miscellaneous Publications of the University of Kansas Museum of Natural History 20: 1 – 224.

[20] Lymnaea (Galba) obrussa Say 1825 is a junior synonym of Lymnaea humilis Say 1822.  See:

  • Exactly 3ish American Galba [6July21]

[21] The scale on Leonard’s entire Plate 1 is dubious.  He stated, “figures enlarged approximately 2 times natural size,” but I do not know the original size of the printed page.  I’m working from a pdf.

[22] Clarke, A. (1973) The freshwater molluscs of the Canadian Interior Basin. Malacologia, 13, 1-509

[23] The radula of Lymnaea (Stagnicola) elodes also bears bicuspid first marginals.  I do not agree with Clarke about the synonymy of L. alberta, but am loathe to digress further.  It clearly is not bulimoides.  That's the point.

[24] 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 that agency in 1982.  It was also serially published in the journal Walkerana (1980, 1982, 1988) and finally as stand-alone volume in 1989 (Malacological Publications, Hamburg, MI).

[25] Stephen, B. J. (2015)  Species composition of Nebraska’s freshwater gastropod fauna: A review of historical records.  American Malacological Bulletin 33: 61 – 71.  For a review, see:

  • Cornhusker Freshwater Gastropods [11May15]

[26] Remigio, E.A. and Hebert, P.D. (2003) Testing the utility of partial COI sequences for phylogenetic estimates of gastropod relationships.  Mol. Phylogenet. Evol. 29 (3), 641-647.

[27] Remigio,E.A. (2002) Molecular phylogenetic relationships in the aquatic snail genus Lymnaea, the intermediate host of the causative agent of fascioliasis: insights from broader taxon sampling, Parasitol. Res. 88 (7), 687-696

[28] Wethington, A.R., & C. Lydeard (2007) A molecular phylogeny of Physidae (Gastropoda: Basommatophora) based on mitochondrial DNA sequences.  Journal of Molluscan Studies 73: 241 - 257.

[29] Correa, A.C., J.S. Escobar, O. Noya, L.E. Velasquez, C. Gonzalez-Ramirez, S. Hurtrez-Bousses & J-P. Pointier (2011)  Morphological and molecular characterization of Neotropic Lymnaeidae (Gastropoda: Lymnaeoidea), vectors of fasciolosis.  Infection, Genetics and Evolution 11: 1978-1988.  I reviewed that paper in my post:

  • The Lymnaeidae 2012: Fossarine Football [7Aug12]

[30] Alda, Pilar, M. Lounnas, A.Vázquez, R. Ayaqui, M. Calvopiña, M. Celi-Erazo, R.T. Dillon Jr., L. González Ramírez,  E. Loker, J. Muzzio-Aroca, A. Nárvaez, O. Noya, A. Pereira, L. Robles, R. Rodríguez-Hidalgo, N. Uribe, P. David, P. Jarne, J-P. Pointier, & S. Hurtrez-Boussès (2021) Systematics and geographical distribution of Galba species, a group of cryptic and world-wide freshwater snails.  Molecular Phylogenetics and Evolution 157: 107035. [pdf] [html]  I reviewed that paper in my post:

  • Exactly 3ish American Galba [6July21]

[31] I speculated that L. bulimoides might be a junior synonym of L. cubensis/viator in both of the blog posts cited above.  But in my own defense, see my footnote #11 of 6July21: “I am quite certain, however, that the single 16S sequence uploaded to GenBank by Remigio, labeled “Fossaria bulimoides” but collected 2,000 miles from the bulimoides type locality in Oregon, is weak evidence, indeed.”

[32] Morningstar,C.R., Inoue,K., Lang,B.K. and Berg,D.J.  (2018) A comprehensive status, phylogenetic, and anatomical review of Stagnicola caperata (Say, 1829) in the south-west United States.  Aquatic Conservation 28 (3), 527-534.

[33] OK, maybe a little further.  Our good friend Amy Wethington tells me that she got her sequences from Rob Guralnick, who got them from a Mesa County, Colorado sample identified as Lymnaea bulimoides by Shi-Kuei Wu.  Shi-Kuei was a careful worker, and thumbing through his (admirable) Colorado Inventory [34] I find no evidence that he was confused about the identity of L. bulimoides.  I have no idea what happened here.  Classic GenBank SNAFU.

[34] Wu, S-K. (1989) Colorado Freshwater Mollusks. Natural History Inventory of Colorado, no. 11. Boulder: Univ. Colorado Museum.

[35] Correa, A.C., J.S. Escobar, O. Noya, L.E. Velasquez, C. Gonzalez-Ramirez, S. Hurtrez-Bousses & J-P. Pointier (2011)  Morphological and molecular characterization of Neotropic Lymnaeidae (Gastropoda: Lymnaeoidea), vectors of fasciolosis.  Infection, Genetics and Evolution 11: 1978-1988.

[36] Shaw, J.N. and Simms, B.T. 1929. Galba bulimoides Lea an intermediate host of Fasciola hepatica in Oregon.  Science 69: 357.

Tuesday, January 9, 2024

Three New Fontigens From Virginia

Editor's Note - This essay was previously published as: Dillon, R. T., Jr. (2023b) Three new Fontigens from Virginia.  pp 225 - 232 in The Freshwater Gastropods of North America Volume 6, Yankees at The Gap, and Other EssaysFWGNA Project, Charleston, SC.

The most faithful and attentive subset of my readership might perhaps remember an essay I posted a year ago this past August [9Aug22], wherein I reviewed the four-year journey that ultimately led to the confirmation of a Fontigens cryptica population inhabiting interstitial spaces in the karstland of central Kentucky [1].  Here is a detail that I cannot imagine any of you could possibly remember, no matter how attentive you have been.  About halfway through that essay I mentioned that two of the Fontigens samples Hsiu-Ping Liu sequenced for our big mtDNA gene tree were contributed by “our good friends Wil Orndorff and Tom Malabad of the VaDCR."

Lane Cave (F. hershleri)

Now let me highlight a blessing of the sort I have found gratifyingly common throughout my 40-year professional career, of which I should be more thankful, but which I fear I have often taken for granted.  Completely independent of the Fontigens cryptica research project that Lori Schroeder and I kept on a slow burner in Kentucky from 2017 – 2021, in November of 2018 I received a cordial email from my old friend Wil Orndorff [2], with the subject line “Some Virginia cave and spring snail collections that need you.”  And after a bit of negotiation, a big box containing 61 tiny plastic vials arrived with a thump on my front porch.  The even-tinier gastropod samples enclosed in those 61 tiny vials had been collected by VaDCR Natural Heritage from caves and cave springs all over the Old Dominion, 1998 – 2018.  Holy crap, I replied to Wil.  N=61 is not “some.”

A bit daunted, perhaps, but undeterred, I went to work sorting and identifying Wil’s very large sample of very tiny snails, a process that stretched four months, into March of 2019.  Of the 61 samples, 30 contained only land snails, and 11 contained only freshwater gastropods typical of above-ground habitats: pleurocerids, physids, and so forth.  That left a (still remarkable) 20 samples of hydrobioid cave snails on my lab bench.

Of all 7,999,999,999 people alive in this world today who have not pulled a fire alarm at the Academy of Natural Sciences of Philadelphia in the middle of the night [3], I flatter myself that I have developed the keenest eye for Fontigens.  Those 20 samples included 11 of F. orolibas, 3 of F. bottimeri, 2 of F. morrisoni, 2 Holsingeria, and 2 samples of hydrobioid cave snails unlike any I had ever seen before.

From the Sugar Run Cave System of Giles County, Virginia, (draining west into the New -> Ohio) I found a single sample of 14 individual Fontigens bearing strikingly ovoid shells – much more convex in their outline than any I had ever seen, bearing a depressed apex.  And from Lane Cave in Scott County, Virginia, (draining south into the Clinch -> Tennessee) I found a singleton hydrobioid snail that looked more like an Amnicola or a Lyogyrus than a Fontigens.  I left those two lots unidentified in the spreadsheet I sent to Wil on 1Mar19.  And here is how I closed my email: “After I die, if I’m reincarnated [4] as the second Bob Hershler, I’ll take another look at these.  Not before.”

So two months later, Lori Schroeder and Andrew Berry discovered one single putative F. cryptica living under a rock at a springhead in the Bernheim Forest of central Kentucky [3July2019].  And fight it though I most certainly had for years, I found myself in the Fontigens business.  I contacted Hsiu-Ping Liu out in Denver and prevailed over her to join Lori, Andrew and me in a grant proposal, then set out on that Fontigens-themed tour of the Great Valley of Virginia I described in my essay of last August [9Aug22], upon my return promptly posting my large sample of tiny snails off to Hsiu-Ping for sequencing.

And included among all those control samples of F. nickliniana and F. orolibas and F. morrisoni and F. bottimeri were, quoting now from my email to Hsiu-Ping of 17July19 …

…two extra samples at the bottom of my spreadsheet, labelled “xtr1” and “xtr2.”  I think I told you that Wil Orndorff and our colleagues at the Va-DCR sent me a big shipment of cave snails last fall, from all over Virginia.  Included in that shipment were two samples I absolutely could not identify, one from Sugar Run Cave in Giles County, the other from Lane Cave in Scott County.  Obviously, these are very low priority.  But if, in the (increasingly unlikely) event we had a bit of money left over… my colleagues and I would be most gratified.

The first results came back from Hsiu-Ping in late August of 2019 – an early version of that gene tree I shared with you all on [9Aug22].  And we were immediately impressed by the tremendous interpopulation CO1 sequence divergence within our control species which, you will recall, ended up being the headline of the paper we ultimately published in 2021 [1].  But the intraspecific variance did not swamp out the sequence variation among species, which ranged from a bit less than 9% up to a bit more than 20%.  And the mean sequence divergence between three snails sampled from the Sugar Run Cave System and their nearest genetic neighbor (F. morrisoni) was 9.0%, and that between our singleton from Lane Cave and its nearest neighbor (one of the F. nickliniana populations) was 13.2%, strongly supporting the specific status of both those “xtr” populations.

Sugar Run Cave (F. benfieldi)

Again, I must emphasize.  I would never dream of looking for new species on a gene tree.  But I brought a hypothesis with me to the analysis that Hsiu-Ping so ably executed in August of 2019, arising from my understanding of the biology of the organisms I was studying.  I predicted that the Lane Cave and Sugar Run populations might represent heretofore undiscovered species of Fontigens.  And testing that hypothesis with a gene tree, I found that it was supported.

And so, I surrendered to the inevitability that I myself would be duty-bound to describe a couple new species of Fontigens in this life, rather than the next.  So, on 29Aug19 I wrote to Wil & Tom:

“Do you have any plans to return to either Lane Cave or Sugar Run Cave any time soon?  We really need more snails.  If you could find a decent sample size (I would love N = 30) I myself would be game to dissect them and describe them formally.  I’m not Bob Hershler, so need a bunch of extras, so I can screw up.  Species descriptions are not my forte, but it needs to be done, and I don’t know anybody else who could do it.”

The answer turned out to be an enthusiastic yes.  It materialized that over the previous nine months, Wil and Tom had continued to stomp all over the Commonwealth, lowering themselves upside down into every hole large enough to lose a basketball, scouring the inner recesses of the Old Dominion for Fontigens.  Although they had not revisited either Lane Cave or the Sugar Run Cave System by that point, they had already collected 12 fresh samples, which they were pleased to send me in September of 2019.  And in February of 2020, yet another fresh batch of 10 Fontigens samples arrived on my doorstep, this one including N = 3 from Lane Cave, N = 18 from the Sugar Run Cave System, and N = 39 from a new sampling location, Dulaney’s Cave, which turned out to be the most interesting of all.

At this point, a boxed essay on the environments from which these populations were sampled might be helpful.  Lane Cave is developed in Cambrian Marysville Limestone atop a bluff running parallel to Copper Creek of the Clinch River drainage, a tributary of the Tennessee.  The cave is a not-insubstantial 0.8 km long and about 60 m deep.  The stream running through it seems to be fed by multiple, small surface sinks at the top of the bluff, and apparently resurges at a spring tributary to Copper Creek.

The Sugar Run Cave system, 170 km northeast, is much larger and more complicated. Developed 200 m deep in Ordovician limestone on the northeast flank of Sugar Run Mountain, the system includes at least 45 km of passages, multiple streams and multiple entrances, the relationships among which are poorly understood.  The sample that Tom & Wil sent me in February labeled “Dulaneys Cave” came from waters connected to subterranean Sugar Run through some unknown passage, all of which ultimately drains into Walker Creek of the New (-> Ohio) River system.

Dulaney's Cave, elongate (F. davisi)

And when I dumped that little plastic vial labeled “Dulaneys” into a dish under my dissecting scope, my eyes were met by quite the unexpected sight.

Yes, I counted N = 31 of those strange Fontigens bearing the unique ovoid shells I had previously seen in the Sugar Run samples.  But plopped right in the middle of those 31 were N = 8 individuals of what looked like yet another species of Fontigens – a third one – I had never seen before.  These bore shells that were larger, and darker, and elongate/pupoid in overall outline.  Good grief!

So I started my dissections.  And of course, after each dissection I saved all the tissues for sequencing.  And in March of 2020 I pitched Hsiu-Ping on the possibility of a second project, beyond the Fontigens cryptica project to which we were already obligated, describing three new Fontigens species from Virginia.

Well, by that point pretty much all the college campuses nationwide were in the grip of the Coronavirus panic.  But Hsiu-Ping, bless her heart, moved her lab into the basement of her private home, and with perhaps even less distraction than she might have otherwise suffered in an ordinary spring semester, was happy to collaborate. 

And in so in May of 2020 I sent Hsiu-Ping two fresh samples of the Lane Cave unknown, three from Sugar Run, and three from Dulaney Cave.  I told her that the Dulaney sample looked like two different shell phenotypes to me, elongate and ovoid, although I didn’t tell her which tubes held which phenotype.  And by that point I was aware of the anatomical similarity between the Dulaney/Sugar Run snails and Fontigens orolibas.  So I also sent her a fresh control sample of F. orolibas from nearby Tawney’s Cave [5] as well.

Baysian Tree abbreviated from [6]

The CO1 gene tree above is an abridged version of the tree Hsiu-Ping sent me in March of 2021, showing just one individual per population.  The full-featured model, which you can see in the Appendix of Volume 5 [6], was based on N = 47 individual Fontigens, including 3 individuals from Lane Cave, 6 from Sugar Run, 2 Dulaneys-elongate, 1 Dulaneys-ovoid, and 2 from the control orolibas at Tawney’s Cave.  Most of the data (shown in black) were borrowed from the F. cryptica study of Liu et al [1] published in 2021.  The sequences in blue are new.

Marked in red are the minimum sequence divergences between each of our three putatively new species and its nearest neighbor, all greater than the minimum intraspecific distance we set in our 2021 paper.

The bottom line was just published last month as an appendix to FWGNA Volume 5, by Dillon, Malabad, Orndorff and Liu [6].  The two new Fontigens species from the Sugar Run / Dulaney system are both members of the orolibas group, bearing a tripartite penis with one tubular and one bulbous accessory gland.  The bodies and eyespots of both species are unpigmented.  I was pleased to name the population bearing ovoid shells for Dr. Ernest F. (Fred) Benfield, my undergraduate mentor at Virginia Tech [7], and the population bearing elongate shells for Dr. George M. Davis, my graduate mentor at the ANSP [8].

The Lane Cave Fontigens is a member of the nickliniana group, its tripartite penis bearing two tubular glands.  Its body and eye spots are pigmented.  These observations, together with the fact that our collections arrived in a mixture with juvenile above-ground-dwelling Pleurocera simplex (Say), suggest to us that the Lane Cave Fontigens might be capable of living in surface waters.  This new species I was gratified to name in honor of my buddy, Bob [3].



[1] Liu, H-P., L. Schroeder, A. Berry, and R.T. Dillon, Jr. (2021) High levels of mitochondrial DNA sequence divergence among isolated populations of Fontigens (Truncatelloidea: Emmericiidae) in eastern USA. Journal of Molluscan Studies 87. [pdf] [html]

[2] You might remember Wil as the leader of that expedition I undertook into Unthanks Cave way back in 2007, as described in:

[3] For a review of the professional contributions of Dr. Robert Hershler, together with a well-curated anecdote or two more personal in their nature, see:

[4] To be very clear, I am a Presbyterian.  If I find myself reincarnated as anything – be it cow, bug, malacologist or Methodist – I shall be most disappointed.

[5] Two of our previous [1] orolibas populations (including the topotypes) came from Atlantic drainages, and the third was from a Tennessee drainage.  So since the Sugar Run Cave system drains toward the New River, we felt as though a fourth orolibas control (Tawney’s Cave) was necessary.

[6] 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. [pdfOrder your copies today!

  • FWGNA Volumes 5, 6, and 7 Now Available! [6Dec23]

[7] Fred Benfield made cameo appearances in my essay of 6Apr23 (Growing Up With Periwinkles) and in my essay of [6May14], (To Identify a Physa, 1975).  Look at footnote #16 of the 2014 essay for a sample of Fred's memorable advice.

[8] George Davis costarred with Steve Ahlstedt in my essay of 5Apr22 (The Ham, the Cheese, and Lithasia jayana) and made cameo appearances in [28Mar22], [11Mar19], and [16July10].