Paul
The shell measures 27.4 x 14.3mm and 10.7 thick
I used a Photoshop filter to make that Menu>Filter>Stylize> Emboss (but that one was quite lousy...)
This was probably one of those shells which came with tons of other stuff and I put aside thinking
"I don't have to label it, I know where it came from..." then 10 years passed. (dumb me, I can't
even remember what I ate for dinner last night!)
Regards
Marcus
________________________________________
De: Conchologists List [mailto:[log in to unmask]] Em nome de Paul Mikkelsen
Enviada em: quarta-feira, 4 de julho de 2007 13:52
Para: [log in to unmask]
Assunto: Re: RES: Donax sp. (Happy 4th of July!)
D. vellicatus was also discussed and figured by Romer, 1870 in which "D. vellicatus" was figured 4
times (plate 7, numbers 10, 11, 12, 13).
I have an original of Romer 1870; most of the illustrations in this work explicitly delineate the
pallial sinus (using a fine, solid black line or black stippling), when the interior of a shell is
figured... indicating much attention to these details throughout the work.
The illustration (number 11) of the interior of vellicatus shows NO pallial lines drawn in.
...is Romer's figure of vellicatus incorrect? ...or perhaps simply incomplete?
The shell that is illustrated by Romer seems, at first glance, to be more elongate-oval, i.e, dorsal
& ventral margins more parallel (vs. the trigonal shapes of D. variabilis roemeri and Marcus'
specimens). Assuming both are images of adult specimens, I've resized and superimposed Romer's
illustration with Marcus's photo and (to my amazement) not a bad match!
For lack of a better place for me to easily display a web page and images, they have been placed
temporarily on my www.seabean.com site:
http://www.seabean.com/donacidae/guide/Donax_vellicatus/index.htm
And a comparison & overlay of vellicatus (Romer's fig. 10) and Marcus's photo:
http://www.seabean.com/donacidae/guide/Donax_vellicatus/composite.htm
Marcus:
How large (length, height, width) are the specimens (or a specimen) in the photo that you
provided?
Your photos are great, particularly those showing the interior and pallial lines!
Any special technique used to achieve the definition shown in the photos of the interior?
Cheers,
Paul Mikkelsen
..spending July 4th looking at Donax!
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Harry G. Lee wrote:
Caro Marcus,
Thanks for the sentiment above. I spent July 4, 1965 na Bahia and consumed a coconut full of
cachaça. That was a memorable holiday, but less so that the following day.
Nice photo's. The interior views confirm a small (for this genus) pallial sinus, which feature,
along with the protracted posterior portion of the disc, help distinguish this species, Donax
vellicatus, from Donax variabilis roemeri Philippi, 1849, which is conchologically by far its
closest congener. John and Leslie are in good company: Macsotay and Campos Villarroel (2001:
174-175; no fig.), citing Andrews' (1971: 189) "D. variabilis texasianus," a misidentification of D.
v. roemeri, place (I think) D. vellicatus in Venezuela, consistent with Morrison's zoogeography.
Morrison put the southeastern terminus of D. v. r., which he called D. r. r., at Yucatan and the
northern terminus of D. vellicatus at Belize.
Incidentally, since Reeve gave a "?" as the "habitat," Morrison designated Praia Upanema, Ariea
Branca, Rio Grande do Norte, Brasil, where the species was unusually abundant, as the type locality
for D. vellicatus (ANSP 300325).
D. vellicatus of Diaz and Puyana (1994: 94; pl. 27, fig. 254) may not be that species. Furthermore,
I believe that D. higuerotensis Weisbord, 1964 from Venezuela is a good species and not a synonym of
D. vellicatus as indicated by Morrison. There is apparently another chapter yet to be written in the
western Atlantic coquinas!
Andrews, J., 1971. Sea shells of the Texas coast. Univ. Texas, Austin, xvii + pp. 3-298 incl.
numerous text figs.
Diaz, J. M. and M. Puyana H[egedus]., 1994. Moluscos del Caribe Colombiano. Un catálogo ilustrado.
Fundación Natura, Sta. Fe de Bogota, Colombia, pp. 1-291 + 78 pls.
Macsotay, O. and R. Campos Villarroel, 2001. Moluscos representativos de la plataforma de Margarita
-Venezuela - descipcion de 24 especies nuevas. Rivolta, Valencia, Venezuela iii + 1-280 incl. 32
pls. July.
Harry
At 08:06 AM 7/4/2007, you wrote:
Oi Harry
Yes, I wish we had labels in every single shells we receive when we buy huge lots of shells.... I do
not think these came from North Brazil, the way it was stored (inside a zip lock bag) looks like
someone gave to us, possibly at a COA convention (damned ADD).
So for locality I have:
Second drawer of my messy cabinet (where I store stuff like these), under a pile of boxes, 1.5
meters from floor level, coll. by M Coltro, July 2007....
I made more pictures with some details, maybe you can see something you didn't notice before
http://www.wonderphotos.com/shellphotos/donax.jpg
I will verify your suggestion anyway, as well Leslie's. Thanks!
Marcus
PS. I will check if I have this volume of Nautilus
Assunto: Re: Donax sp.
Dear Marcus,
Naughty, naughty! Of all people I would have expected you to keep track of your labels.
These appear to be Donax vellicatus (Reeve, 1855), which ranges from Belize to northern Brasil. It
"travels under the radar" as the sympatric and roughly syntopic D. denticulatus Linnaeus, 1758 and
D. striatus Linnaeus, 1767 seem to get found in far greater numbers and at more stations. Besides
Reeve, it is illustrated in Morrison (1971: pl. 1, fig V, pl. 2, fig V) and Petuch (1998: 31, fig
43, as D. mediamericanus Pilsbry 1919 [sic] [1920], which is a synonym of D. striatus according to
Morrison).
Although Donax Linnaeus, 1758 was treated by its author and many subsequent workers (e.g. Morrison)
as a feminine noun (see Dodge, 1952; p. 78), it is a Greek masculine, and, as mandated in Article
30.1.2 (and not meeting any of the exceptions in 30.1.4) of the International Code of Zoological
Nomenclature (ICZN, 1999), should always be treated as such nomenclatorially. I notice that Femorale
does this correctly on your fine website.
Morrison, J. P. E., 1971. Western Atlantic Donax. Proc. Biol. Soc. Wash. 83(48): 545-568.
Petuch, E. J., 1998. The molluscan fauna of the Wawa River Region, Miskito Coast, Nicaragua:
ecology, biogeographic implications, and descriptions of new taxa. The Nautilus 111(1): 22-44. Jan.
29.
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