Linda

I jumped the gun when I saw your e-mail, I was thinking M. ambiguus all along.
If you take a good look at the shells on my webpage you will see that they
are distinctly
different in a lot of ways.  These differences are consistent even when the
two species are found next to each other.  I am not an expert but I and my
other friends who have collected
these have always thought them to be two separate species.  I have found M.
ambiguus at El Golfo in Sonora, so they are not confined to S. Mexico.

Cheers

Rick

At 10:31 AM 9/3/2003 -0400, you wrote:
>Hi, Again, Rick!
>
>I have one question.  Myra Keen regards ambiguous as an
>intermediate form betwenn the northern M. nigritis and the
>souther M. radix (yes, I know the genera have been
>changed).  She gives the range of radix as from Panama to
>southern Ecuador, and the range of nigritis as confined to
>the Gulf of California.  She then regards ambiguus as
>possibly not a distinct species, but as a transitional
>form between the two species, with a range of Southern
>Mexico to Panama.
>
>What is your take on this?
>
>Cordially,
>Linda