Posted: Jan 11 2010
Cerithiopsis greenii (C. B. Adams, 1839), Green's Miniature Cerith
My original presentation in Jan 2010 of a specimen from Florida was of a shell that Harry Lee and I believed "could be" C. greenii based upon the state of knowledge at the time. We came to doubt that it was and our researches since then have concluded it was not, and that the true C. greenii is restricted to the NE Western Atlantic.
In Jan 2010 I wrote:
"Cerithiopsis greenii (C. B. Adams, 1839) is probably a valid species with a distribution at least along the eastern seaboard of the USA from the NE to Florida and may occur on Florida’s west coast. (We have since concluded that C. greenii is restricted to the USA NE Atlantic region.) Abbott, Malacolog and The Bailey-Matthews Museum report C. greenii as occurring on both of Florida’s coasts. The Florida Museum of Natural History does not have records of this shell from Florida. Harry Lee’s NW Florida and Peanut Island checklists do not include C. greenii and his Cedar Key checklist includes C. cf. greenii. The problem with having too much confidence in these reports centers upon the protoconch. Adams did not indicate the number of whorls composing the protoconch of C. greenii, but did indicate that the protoconch was “smooth, nearly white and pearly.” When Rolán (1995) examined the lectotype he noted that only a small portion of the protoconch was present and was “light brown.” My few samples of what I would call C. greenii have light brown protoconchs with one having a white protoconch. Based upon the ambiguity with the protoconch, the frequency that Cerithiopsis are found with the protoconch missing, and the fact that C. greenii can superficially resemble other Cerithiopsis found in Florida, such as C. fusiformis, C. dominguezi, and C. academicorum, the latter two of which were only recently named in 1995, it would not be surprising to find that many Florida shells identified as C. greenii are indeed one of these other species. The reason I question the validity of prior identifications is that, after 15 years collecting Florida shells (with a focus on micromollusks), I have found less than a half dozen that sufficiently fit Adams’ description as to be reasonably separated from the other three, but could not be defined as being C. greenii with complete certainty. While these four species can be separated, it does require an awareness of all of them and a close examination of the first two teleoconch whorls, which is not easy with these very tiny shells and requires significant magnification.
4/23/14 We have concluded our investigation and our findings were published in American Conchologist, first quarter of 2014, Vol. 42, No. 1, copy below.