Michael Hoelling asked about the reasons why the time-honed genus Lunatia
Gray, 1847 should be replaced by the genus Euspira Agassiz in J. Sowerby,
1838.
Well, as the authorship dates show, Euspira has some nine years precedence
over Lunatia. Of course, this will be of consequence only if those two genera
are in fact based on the same generic concept. How can this be verified? The
answer is, if the type species designated to "represent" these two genera are
congeneric, then the older name takes precedence and the younger one slips
into synonymy.
So the question now has been moved to another level: Are the type species of
Euspira and Lunatia congeneric? If the type species of the two genera were the
same species, things obviously would be easy: the junior genus would be an
objective synonym of the older one. If they are not, as is the case here,
things become considerably more complicated.
The type species of Lunatia is Natica ampullaria Sowerby (which is a synonym
of the well-known Western Atlantic species Natica heros Say, 1822), and was
originally designated by Gray when he proposed the genus in 1847.
The type species of Euspira is the fossil species Natica glaucinoides J.
Sowerby, 1812 (a synonym of Natica labellata Lamarck, 1804) which was
subsequently (in 1883) designated by Bucquoy, Dautzenberg & Dollfus.
Are these two type species congeneric? When Agassiz erected the genus Euspira
in 1838 in his annotated German translation of J. Sowerby's famous "The
Mineral Conchology of Great Britain", he gave the following definition [I
translated this from the German original]:
"Those species of Natica which are distinctly conical with clearly visible
whorls and which do not have a spiral funicle in the umbilicus form a special
devision of the genus which I call Euspira....."
This definition of Euspira as well as the figures by J. Sowerby obviously fit
perfectly the characteristics of a typical Lunatia such as its type species
"heros Say, 1822". The first one to recognize this was Stoliczka in 1868 (Mem.
Geol. Surv. India 5: 296). William H. Dall in 1908 (Bull. Mus. Comp. Zool.
Harvard 43: 334) and 1909 (U.S. Geol. Surv. Prof. Pap. 59:87) also noted the
congeneric nature of the two genera, as did Marincovich in his classical 1977
revision of the northeastern Pacific Naticidae (Bull. Amer. Paleont. 70: 264).
Finally, Alan Kabat in his 1991 paper "Classification of the Naticidae: Review
and analysis of the supraspecifc taxa (Bull. Mus. Comp. Zool. 152: 431) also
supported this conclusion.
As Michael Hoelling pointed out, Thiele (1929-1931) did not mention the genus
Euspira. Most likely, he was not aware of this name. Other popular authors who
do not mention Euspira may simply have followed Thiele.
As Michael Hoelling correctly stated, Gert Lindner listed Euspira in the
Naticinae, and Lunatia in the Polinicinae which would mean they could not be
congeneric, being in different subfamilies. Lindner may have followed Wenz
(1938-1944) in this assignment. Wenz gave no explanation or justification for
his decision and may not have been aware of the proposed synonymity of Lunatia
and Euspira. By the way, in addition to Euspira Gert Lindner also listed the
genus Payraudeautia in the Naticinae (at least in the 1982 edition of his book
which I consulted). This is clearly incorrect as the type species of
Payraudeautia, the common Mediterranean species P. intricata Donovan, 1804,
has a horny operculum, proving that the species definitely belongs into the
Polinicinae. Since Gert is on Conch-L, he might want to comment on this.
To summarize, when one goes back to the original descriptions and figures I
think there can be little doubt that the diagnoses of Euspira and Lunatia
pertain to the same group of species, making them congeneric. Therefore,
Euspira Agassiz in J. Sowerby, 1838 should be the correct generic assignment
for all species formerly included in Lunatia Gray, 1847, the latter thus
becoming a subjective junior synonym.
Michael Hollmann
N.B.: As a further complication, several different editions of Agassiz's
German translation of J. Sowerby's "The Mineral Conchology of Great Britain"
appear to exist, which all have slightly different title pages and publication
dates. Alan Kabat noted that the earliest edition actually was published in
1837 [July, 25] rather than in 1838.
Thus, the correct designation should be "Euspira Agassiz in J. Sowerby, 1837",
which gives Euspira a full 10 years precedence over Lunatia Gray, 1847.
******************************************
Dr. Michael Hollmann
Goerdelerweg 17
D-37075 Goettingen
GERMANY
Tel.: (home) (49)-551-22356
Tel.: (work) (49)-551-3899-437
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