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Hirsute Hermaphrodite Hobo from Eurasia working his/her way through Cornell |
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By Harry G. Lee |
| Awaiting the airport shuttle vehicle while
concluding a short stay at the La Tourelle Inn on the outskirts of Ithaca,
New York, I decided to take a look around a half-acre artificial "fishing
pond" on the spacious premises. The setting was a picturesque pasture-like
hillside overlooking Cornell University and Lake Cayuga and to the north
and northwest. Although overcast, the temperature was mild for a
mid-November day; Ithaca had yet to receive more than token snowfall this
autumn. Ignoring the few gawkers, I nosed around the pond's margins and easily found a fair number of living landsnails on the lawn, especially under hewn larger weeds. There were four species - Novisuccinea ovata (Say, 1817), Cochlicopa lubrica (Müller, 1774), a small nearly black slug, and, most abundantly, a quarter-inch globose snail I thought to be a Slit-mouth (Stenotrema)* of some sort because of its having Pussy-willow-bud-like texture. I popped the snails into an evacuated (and thoroughly-rinsed) shampoo sampler supplied by the inn, pocketed the collection, and shuttled to the Ithaca Airport. While languishing in La Guardia, I couldn't resist the urge to retrieve the "collecting vial" and inspected the shells more closely. I noticed that a densely hirsute Stenotrema-like periostracum accounted for the shell's unusual surface but no evidence of the thickened lip and constricted aperture that characterizes that North American genus. After some reflection, and prompted by a flicker of déjà-vu, my mind finally broke loose from the box, and I considered this critter might be a non-native species. |
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Note (6/18/2008): Trichia Hartmann, 1840, of which this is the type species by subsequent designation (Herrmannsen, 1849), is actually a junior homonym of the crustacean genus Trichia De Haan, 1839. In 2004 a petition for the conservation of the Hartmann nomen was rejected by the International Commission for Zoological Nomenclature (ICZN), and the earlier Trochulus Chemnitz, 1786, was considered an objective synonym and placed on the Official List of Generic Names. [Bull. Z. N. 61(3): Opinion 2079 (Case 2926) 30 Sept. Thus the vagabond is more properly referred to as Trochulus hispidus.
*Note (12/20/09): In his description of
Helix hirsuta, Thomas Say (1817: 17) made comparison to Trochulus
hispidus (then Helix hispida). Say's species was ultimately
placed in Stenotrema Rafinesque, 1819, in which genus, although
not the type species, it is the first described. Thus I was not the
first to appreciate the similarity between the two convergent taxa. |
On arrival in Jacksonville that night, despite temporary dismay with the
Jaguars' last minute loss to the Titans, I went to microscope, collection,
and books to sort out the identity of this probable vagabond. Conclusion:
I had picked up my second batch (the first was in ME on my 45th birthday)
of Hairy Helicellid, a species native to northwest Europe east through
northern Asia, where it reaches the Amur River. The scientific cognomen is
Trichia hispida (Linnaeus, 1758) (see
first note at bottom of page) [literally: the Hairy (Latin),
Hairy (Greek) Snail], and its taxonomy goes like this: Mollusca:
Gastropoda: Stylommatophora: Pulmonata: Helicoidea: Hygromiidae:
Hygromiinae. Since I wondered how far and how long it had traveled in
North America, I dug further into my library and found
no mention of the species in a host
of state and regional surveys including NH, CT, NY, NJ, OH, IN, IL, MI,
and WI. Nonetheless, I found a few references and, using the Internet
(including good advice from my friends on the Conch-L list-serve), patched
together the following summary over about a ten day period: