Racking brain over 2 Fulgoraria species

[sakura-of-the-sea]

I recently obtained 4 of a Fulgoraria genus but cannot pinpoint which of possible two species they could be. I looked through field guides & online catalogs & see no visible difference between F. rupestris & F. hamillei, which are the only two species they could possibly be. I see they both have the same shape, similar size, location & markings & can both be variable in pattern.

This is frustrating, considering I can usually find the identity of most marine gastropods fairly quickly. And I rarely keep ones I cannot positively identify. Any minute details I may have missed to tell the two species apart? Thanks for your help.  <span class="petit">--Last edited by sakura-of-the-sea on 2009-05-20 08:34:12 --</span>

[dave r]

The only difference I have head of is that F. rupestris has a slightly larger protoconch, other than that I think it is down to soft parts.
Dave

[sakura-of-the-sea]

I was afraid of that. Thanks for your help, Dave.

[paul monfils]

Yes these are typical F. hamillei.

[paul monfils]

The pattern in F. rupestris usually consists of distinct stripes from suture to anterior end. They may be quite straight or rather meandering, but generally maintain fairly sharp edges along their entire length. In F. hamillei there is usually lateral "smearing" of the pattern, especially in a broad band at mid-body, and often along a narrower sub-sutural band as well.  The edge of the lip is quite strongly crenulated in F. rupestris, uncrenulated or barely crenulated in F. hamillei.  The shoulder is more rounded in F. hamillei, more angular in F. rupestris.  Also. F. hamillei grows larger.  A specimen over 125 mm is almost certainly F. hamillei.  But of course this doesn't help for smaller specimens.  Can you provide a picture?  <span class="petit">--Last edited by PAUL MONFILS on 2009-05-20 06:15:38 --</span>

[sakura-of-the-sea]

Thanks a lot, Paul! By the way, I looked both species up in several field guides I own & said that they were both uncommon. My most recently published book was in 2000. Has that changed in the last 9 years?

[sakura-of-the-sea]

Just testing to get the feel of this. Good! It did work!
Okay, this is the apertural view.
Sorry it's fuzzy, lighting sucks in my home.
<img src="http://photos-a.ak.fbcdn.net/photos-ak-snc1/v4406/187/108/1612576394/n1612576394_200280_7494711.jpg" alt="http://photos-a.ak.fbcdn.net/photos-ak-snc1/v4406/187/108/1612576394/n1612576394_200280_7494711.jpg" style="border:0" />

And the dorsal view:
<img src="http://photos-b.ak.fbcdn.net/photos-ak-snc1/v4406/187/108/1612576394/n1612576394_200281_1079213.jpg" alt="http://photos-b.ak.fbcdn.net/photos-ak-snc1/v4406/187/108/1612576394/n1612576394_200281_1079213.jpg" style="border:0" />

I'm thinking hamillei, what do you think?  <span class="petit">--Last edited by sakura-of-the-sea on 2009-05-21 08:48:02 --</span>

[paul monfils]

I'd say that F. hamillei is uncommon, and F. rupestris "moderately common". In any case, F. hamillei is considerably less common than F. rupestris.  I haven't found books very helpful in this regard.  Some books list very common shells as "uncommon", and vice versa.  The new Philippine Marine Mollusks, while a very useful identification guide with great photography, lists many species as "uncommon" or even "rare", that can be purchased from a dealer for under five dollars.

Here's a shot of a couple of F. rupestris for comparison with your shells.  Another difference I forgot to mention above is that the spiral grooves in the body whorl are deeper and more obvious in F. rupestris.

<a href="http://members.cox.net/natura/Frupestris.jpg" target="_blank"><!-- m --><a class="postlink" href="http://members.cox.net/natura/Frupestris.jpg">http://members.cox.net/natura/Frupestris.jpg</a><!-- m --></a>

[sakura-of-the-sea]

Boy if that's true then I need to find a way to get my hands on some of those!

I see what you mean now, as far as the angular whorls and the unbroken stripes. I also noticed that the lip is significantly thicker than my hamillei. I didn't notice that before. This photo better differentiates rupestris from mine. Thanks again, Paul!