Editor’s Note – This essay was subsequently published as: Dillon, R.T., Jr. (2023b) The Return of Captain Lyon. Pp 81 – 88 in The Freshwater Gastropods of North America Volume 6, Yankees at The Gap, and Other Essays. FWGNA Project, Charleston, SC.
“One man only remained behind. It was Captain Sidney S. Lyon, of Jeffersonville, one of Indiana’s most gifted engineers. As the Federal army moved away, he sat down upon a rock and waited. Beside him lay a black, snake-like rope, the end running into the steep side of the mountain. It was a fuse. He had mined the mountain and filled the hollow with all the powder the fleeing army could spare…The tramp of the marching died away; the commissary stores were burning, and still he sat, as the night fell over the heights and the darkness filled the ravines. Were the Confederates coming? He heard the faint hoof-beats, the rumble of a great force of men coming from the Tennessee side. There was the sparkle of a match, the splutter of powder, and a man fleeing down the mountain toward Kentucky for his life, and then…”
I honestly don’t know
to what extent The Blowing of Cumberland Gap is true [1], but it does not
matter, because it’s a great story, and I would recommend that you look up the
Lyon family history [2] from google books and read pp 185 – 192, if you want to
know how it turned out. Or, if you would
rather read my tenth (and final!) essay on the shell morphological variation
and taxonomic confusion in the pleurocerid snails of the Tennessee/Cumberland
in twelve months, soldier on below.
 |
| Sidney Smith Lyon (1808 - 1872) |
In the fall and winter of 2016, a duller 154 years later, I spent a couple weeks in Frankfort, Kentucky, working with our good friend and colleague Ryan Evans on the freshwater gastropods of the Bluegrass State. I had been surveying the region in preparation for the roll out of our new FWGO web resource for several years and, at that juncture, fancied myself familiar with most elements of the freshwater gastropod fauna of the Ohio River basin. But what I found in KYDOW macrobenthic samples from little tributaries of the Green River, and even in some little creeks draining directly into The Ohio in western Kentucky, surprised me. To the point that I can still remember it four years later. Which at my age, is saying a lot.
I was already aware that P. simplex populations, of diverse
shell morphology, extended across the entire drainage of the
Tennessee/Cumberland from SW Virginia to Chattanooga, west through Tennessee
and north into the Ohio River tributaries of Kentucky. But my goodness! Crawling around together with the P. simplex
in the little creeks of western Kentucky, way out beyond Louisville, the KYDOW
teams were also collecting pleurocerids indistinguishable to my eyes from
Pleurocera troostiana, or arachnoidea, or spinella, or strigosa, or striatula,
or whatever else people have called that pleurocerid bearing light, slender,
striate shell with small body whorls in upper Tennessee River tributaries for
almost 200 years. The entire malacofauna
of little creeks in Western Kentucky was indistinguishable from that of East
Tennessee.
The shells of the
particular population I was examining that afternoon were not costate, although
several nearby populations were. That is
what especially struck me about those KYDOW samples, as I sat at the lab bench
in Frankfort back in 2016, in addition to all the above. I was as stricken by what I was not seeing,
as what I was. And this thought suddenly
dawned on me. If a pleurocerid species
bearing a fat-smooth shell, like P. simplex, ranges through little creeks
across four states, why can’t a pleurocerid species bearing a skinny-striate
shell, like P. troostiana?
 |
| Western Kentucky or East Tennessee? |
Let me back up for a bit of context. Throughout Kentucky, and indeed through
Middle Tennessee as well, streams of all sizes and descriptions are often
choked with large and morphologically diverse populations of Pleurocera laqueata (Say 1829). They bear shells
with large body whorls that are sometimes striate but always, always costate. I’d been looking a bottles-full of Pleurocera
laqueata from central Kentucky all week.
Is it possible that some of those samples might be P. troostiana,
slightly costate, not P. laqueata, slightly striate?
Have P. laqueata and P. troostiana been confounded in this
part of the world for 200 years? Have they been confounding each other [3]? Might
the nineteenth-century literature contain dozens of names for both,
subsequently scrambled by synonymy? If
so, what are workers calling the tall-skinny-striate pleurocerids in Kentucky
today [4]?
Following Branson’s [6] “Keys to the aquatic Gastropoda
known from Kentucky” one finds four Goniobasis species “with longitudinal
plicae” (i.e. striations) at any point in their shell growth: laqueata (Say
1829), curreyana (Lea 1841), costifera (Hald. 1841), and plicata-striata
(Wetherby 1876). The type shells borne
by all four of these species are primarily costate, and I think the last three
nomina will prove junior synonyms of Say’s laqueata. Bookmark that question. One day we’ll come back to it.
Reference to the primary literature, however, returns an
excellent paper by Bickel [7] on the biology of pleurocerid populations he
called “Goniobasis curreyana lyoni (Lea 1863)”.
I think that’s it.
 |
| Goniobasis lyonii then [10] and now. |
Lea’s acknowledgement in the ANSP Journal paper [10] was: “I
dedicate this with great pleasure to Mr. Lyon, Civil Engineer and State
Geologist.” War had not yet broken out
between the states at the date of Lea’s writing, and Mr. S. S. Lyon had served
as the topographer for the first (1854 – 57) Kentucky Geological Survey.
But war did come, carrying all American topographers along
with it. And my loyal readership will
remember that it was Capt. Sidney Smith Lyon who stooped to capture two populations
of rebel pleurocerids at Cumberland Gap in the summer of 1862, which he posted
back behind the lines to Isaac Lea in Philadelphia. Lea described that sample under four names in
the smaller PANSP paper of 1863 [11] that kicked off this entire series of blog
posts, way back in [4Aug19].
I counted 20 hits to S. S. Lyon in Isaac Lea’s bibliography
[12], first as Mr. Lyon, then as Capt. Lyon, and ultimately as Maj. Lyon, after
August of 1863. According to the family
history published in 1907 [2], Lyon was an artist, a crinoid paleontologist, a
naturalist, and singlehandedly saved the army of General George Morgan when it
was surrounded at Cumberland Gap in September of 1862. The account extracted at the top of the
present essay was written by one Col. James Keigwin, and lovingly passed down
to us by the Lyon family.
But back to the snails.
Lea’s description of Goniobasis lyonii noted that the shell was “very
much drawn out” and “striate above.” He
did not mention costae but his figure (#156, reproduced above) shows light
costation as well as light striation on the slender shell. Lea gave the habitat as “Grayson County,
Kentucky, S. S. Lyon.” Its subsequent
taxonomic history is Byzantine [14], but it was the substance of Bickel’s 1968
paper that lyonii should be resurrected as a subspecies of curreyana, which I
don’t think it is [15], but I do give thanks for the resurrection.
Bickel restricted the lyonii type locality to Spring Fork
Creek, a tributary of the Rough River in Grayson County, Kentucky. He also reported populations in seven other
small streams in four other counties: Breckinridge, Meade, Hardin, and
Larue. I sampled Spring Fork at three
locations on the morning of 15May19 and was most disappointed by the quality of
the environment, which in the last 50 years has declined to the status of muddy
ditch, and by the population of pleurocerids dwelling therein, which has
dwindled to zero. Providentially, my
database contained three other Grayson County sites at which lyonii populations
had been collected by the KYDOW, and I found a decent population in a tributary
of Big Run Branch, 5 km W of Leitchfield (37.5029, -86.3411). See the example figured above.
 |
| Attributed to S. S. Lyon [13] |
Some populations of P. troostiana lyonii bear shells with
light costation around their apex, rendering them effectively indistinguishable
from P. troostiana perstriata, and some do not, rendering them
indistinguishable from P. troostiana troostiana. I struggled with the suggestion offered above. Ultimately, I decided to preserve the S. S.
Lyon patronymic in the pleurocerid canon more to protect the small (but not
insignificant) literature associated with the taxon than to further any grand
evolutionary hypothesis. Besides which,
I have grown rather fond of the gentleman.
He was not some pompous jackass sitting high-and-mighty behind a walnut
desk in Philadelphia. Capt. Sidney Smith
Lyon did his duty.
Now at last, the time to summarize has arrived, woohoo. Available from the link below is a pdf
download entitled:
Here I have listed and figured all 13 of the specific and
subspecific nomina I have synonymized under Isaac Lea’s Pleurocera troostiana
since last August, together with type (or typical) localities and
references. I have not listed all the
dozens of older synonyms under these nomina, as catalogued by Tryon and
Goodrich. Quoting the latter, “I have not had the heart.” This is FWGNA Circular Number 2 (July 6,
2020).
Notes:
[1] Or maybe they’re lyon?
Sorry, I couldn’t resist.
[2] Lyon, S.E., et al. (1907) Lyon Memorial: Families of
Connecticut and New Jersey, including records of the descendants of the
immigrants Richard Lyon of Fairfield and Henry Lyon of Fairfield. Detroit: William Granham Printing. Pp 185 – 192.
[3] I really think Pleurocera troostiana and P. laqueata hybridize broadly, anywhere and everywhere their ranges overlap. I mentioned this back in essay of [15Apr20] and asked you to bookmark it. And I'm mentioning it again here, and asking you to bookmark it, again.
[4] Back in November we reported that Isaac Lea described
505 species of pleurocerids. Well, Dan
Graf [5] cataloged approximately 500 more, contributed by other authors. Those 1,005 names are a slough of despond
into which I do not intend to fall. So
my approach for 40 years has been first to work out the biology, and then to
work out the taxonomy. First, my
evolutionary intuition suggests that there are approximately 40 biological
species of pleurocerids in North American waters, with another 20 subspecific
nomina that may prove of some utility.
So second, I am trying to figure out what 60 names to call those
populations or groups of populations. Those
60 names may not be the oldest, nor the most familiar; they may be a compromise
between age and modern use. But if I
live to be 107, I will never get to task #3, what the heck most of those other
945 names mean.
[5] Graf, D. L. (2001)
The cleansing of the Augean stables.
Walkerana 12(27): 1 - 124.
[6] Branson, B.A. (1987)
Keys to the aquatic Gastropoda known from Kentucky. Trans. Kentucky Acad. Sci. 48: 11 - 19.
[7] Bickel, D.
(1968) Goniobasis curreyana lyoni,
a pleurocerid snail of west-central Kentucky. The Nautilus 82: 13 - 18.
[8] To quote The Eagles, “You can’t hide your lyon eyes,”
pleural. OK, I’ve got all the corny
jokes out of my system, for now.
[9] Lea, Isaac. (1862) Description of a new genus
(Goniobasis) of the Family Melanidae and eighty-two new species. Proc. Acad.
Nat. Sci., Phila., xiv, pp. 262-272.
[10] Lea, Isaac (1863) New Melanidae of the United
States. Journal of the Academy of
Natural Sciences of Philadelphia 5: 217 – 356.
[11] Lea, Isaac (1863) Descriptions of fourteen new species
of Melanidae and one Paludina.
Proceedings of the Academy of Natural Sciences of Philadelphia 15: 154 –
156.
[12] Scudder, N. P. (1885)
Bibliographies of American naturalists – II. The published writings of
Isaac Lea, LL.D. Bull. US National
Museum 23: 1 – 278.
[13] For more about the “White Horse” painting attributed to
S. S. Lyon, see:
Clark County Museum looking for help to restore historic
painting. News and Tribune (Clark
County, Indiana). February 12, 2018.
[html]
[14] I quote Bickel [7] verbatim: “This animal is Goniobasis
lyoni Lea, 1863, a species that Tryon (1865) placed in the synonymy of
Goniobasis glauca (Anthony). It was
subsequently transferred along with G. glauca to the synonymy of Goniobasis
athleta (Anthony) by Tryon (1873), and Goodrich (1940) shifted it to the
synonymy of Goniobasis laqueata (Say).
Goniobasis lyoni is a form of Goniobasis curreyana (Lea) and is distinct
enough to merit recognition.”
[15] It is hard for me to understand why Dave Bickel thought
lyonii was a subspecies of curreyana.
Lea’s (1843) figure clearly depicts Melania curryana as a laqueata-type,
bearing an aperture “about one-third the length of the shell,” not a
troostiana-type, with aperture smaller.
And Lea specifically stipulated [16] that the shell of curreyana “is
without striae,” focusing instead on the “large and strong folds.” Lea’s (1841) Melania curreyana is clearly a
junior synonym of laqueata (Say 1829) and has nothing to do with his Goniobasis
lyonii of 1862.
[16] Lea, Isaac (1843) Description of New Fresh Water and Land Shells. Transactions of the American Philosophical
Society 8: 163 – 250.
[17] Subspecies are populations of the same species in
different geographic locations, with one or more distinguishing traits. For an elaboration, see:
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