Harry

Jose is right now in the Museum of Natural History in Paris and I've just
told him to try to take pictures of this specimen (if it can be found...)
and more details from the label.

Our shells are not like that illustrated on the article, it looks more like
Texan shells.

Reading the text (using my poor French) I see Dall had access to specimens
from Texas looking like both A. brasiliana and A. incongrua - but where is
the type of A. incongrua?

Marcus



>Dear Markus,
>
>I think it is important to determine just what the species is.
>
>The type locality for Arca brasiliana is Rio de
>Janeiro according to the original description
>(Lamarck, 1818: 44; species 33; see
><http://www.biodiversitylibrary.org/item/47441#page/56/mode/1up>).
>There is no type figure, and the type specimen(s)
>was located exclusively in the collection of
>Jacques-Louis-Marin Defrance (1758-1850).
>Fortunately that collection eventually reached
>the Mus�um National d'Histoire Naturelle, Paris,
>and a probable syntype, a right valve, was
>discovered, discussed, and figured (Lamy, 1906:
>308-309; Fig. 2; see
><http://www.biodiversitylibrary.org/item/55051#page/338/mode/1up>).
>In the discussion, Lamy makes the point that the
>figured shell matches the description (to the
>mm), and "de cette esp�ce, telle que Je l'ai
>pr�ecis�e ici m�me (J. de C., 1904, p. 162*)."
>
>I think the shell can be considered at the very
>least "authentic" if not a well-qualified contender for lectotype.
>
>To me it looks like the R valve at
><http://www.jaxshells.org/anadar.htm>. Does it
>differ from what you call Scapharca brasiliana (Lamarck, 1818)?
>
>Harry
>
>* in this discussion he synonymizes A. incongrua
>Say with the Lamarck species; see pp. 162-164
><http://www.biodiversitylibrary.org/item/55042#page/175/mode/1up>.
>
>
>At 05:51 AM 12/7/2010, you wrote:
>>Thanks Marlo
>>Indeed it looks quite different from what we call A. brasiliana.
>>Somehow I am not receiving message from Conch-L - I had to check if I had
>>any replies directly on Conch-L website.
>>
>>Marcus
>>
>> >Marcus,
>> >
>> >I have only two juvenile specimens from Georgia.  But, Bill has several
>>good
>> >photos at http://www.jaxshells.org/atlanticb.htm (look for Scapharca
>> >brasiliana).
>> >
>> >I can photograph mine if you'd like.
>> >
>> >Marlo
>> >
>> >From: Marcus Coltro
>> >Sent: December 06, 2010
>> >
>> >Is there any subspecies of Anadara brasiliana in Texas?
>> >
>> >Shells from Texas are quite different from the ones from Brazil and
>> >Venezuela.
>> >
>> >Specimens from Texas seems to be more granulose, having wider valves and
>> >looks like their umbus never touch the other side. After the shell
grows to
>> >a certain size both valves touch on the umbus, preventing the shell to
>>open.
>> >It has to grind off the excess moving the valves sideways so it can be
>> >opened again - this produces a hole in both valves - as seen on the
right
>> >specimen from Brazil. I guess since it lives on mud that hole would not
put
>> >the shell at risk from predators.
>> >
>> >Anyway, shells from Texas seems to be something else, not A. brasiliana.
>>Has
>> >anyone studied this group? Maybe Say was right calling it Anadara
incongrua
>> >(assuming the type is from this area)
>> >
>> >http://www.wonderphotos.com/shellphotos/anadara_brasiliana.jpg
>> >
>> >I've never had any specimens from US East coast - what do they look
like?
>> >
>> >Marcus
>

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