Date: Mon, 13 Oct 2003 22:17:16 -0400
Reply-To: Conchologists of America List <CONCH-L@LISTSERV.UGA.EDU>
Sender: Conchologists of America List <CONCH-L@LISTSERV.UGA.EDU>
From: "José H. Leal" <jleal@SHELLMUSEUM.ORG>
Subject: Re: Poecilogony: pairs of species
For more on the Alvania faberi/auberiana pair check my old book (Leal,
1991, Marine Prosobranch Gastropods from Oceanic Islands of Brazil), pages
72-73, plate 7figs. A-I; poecilogony cannot be dismissed just because it
hasn't been confirmed.
At 09:57 PM 10/13/2003 -0400, you wrote:
>This is an excerpt from at report on Stosicia at
> "If we look at other groups in which sympatric pairs of
> closely-related marine snails having utterly different protoconchs much
> as do our two species, a few instances in the Caribbean fauna leap to
> mind in which the teleoconchs are actually even more similar: Alvania
> auberiana (d'Orbigny, 1842) / A. faberi de Jong and Coomans, 1988,
> Retilaskeya emersonii (C. B. Adams, 1845) / R. bicolor (C. B. Adams,
> 1839), and Iniforis turristhomae (Holten, 1802) / I. casta (Hinds,
> 1845). In these cases of so-called didymous species pairs, it is not
> entirely clear to me which is the ancestral and which the derived
> condition, but, in a group taxonomically close to the Stocisia, Verduin
> (1977) looked at European Rissoa species and concluded that the
> lecithotrophic species was the descendant (apomorphic), and the
> planktotrophic was ancestral (plesiomorphic). Similar conclusions were
> reached in a wider taxonomic and/or paleontological context in Ficus
> (Smith, 1945), Trophon (Bouchet and Warén, 1985), Nassariidae (Martinell
> and Cuadras, 1977), Neogastropoda in the early Tertiary and Volutidae in
> the Cenozoic to Recent (Hansen, 1983), Terebridae (Bouchet, 1981), and
> Turridae (Bouchet, 1990). To my knowledge, no instances of the opposite
> pattern of evolution has been reported. In fact, Strathman (1978)
> concluded that plankotrophic development was ancestral to the
> lecithotrophic condition among all marine invertebrates with such life
> histories, and that the reversal of this process was much less frequent,
> even unlikely. A relatively limited geographic distribution of
> lecithotrophic species and their tendency to be less long-lived (in a
> geological sense) than their planktotrophic congeners has been noted by
> several workers including Jablonski (1982, 1986) and Hansen (1983)."
>Rissoidae: Alvania auberiana (d'Orbigny, 1842) [planktotrophic]] vs. A.
>faberi de Jong and Coomans, 1988 [lecithotrophic].
>Triphoridae: Iniforis turristhomae (Holten, 1802) [planktotrophic] vs. I.
>casta (Hinds, 1845) [lecithotrophic].
>Cerithiopsidae: Retilaskeya emersonii (C. B. Adams, 1845) [planktotrophic]
>vs. R. bicolor (C. B. Adams, 1839) [lecithotrophic].
>Although I work with this western Atlantic fauna a lot, I don't think I
>can tell the latter two pairs apart without looking at the protoconch, and
>even these two Alvania are quite a challenge thus deprived.
>At 05:01 AM 10/13/2003, you wrote:
>>the theme of the evolution of larval development in marine invertebrates
>>has been my preferred one during several years. And it was the argument of
>>my very PhD thesis (1994). I have neglected it for a while but I'm still
>>accumulating data about several aspects. One of them is the phenomenon of
>>pais of species. I was thinking about presenting a poster to the next
>>UNITAS congress in Australia (2004).
>Cut to conform to UGa restriction
>Harry G. Lee
>1801 Barrs St.
>Jacksonville, FL 32204
>Visit the Jacksonville Shell Club Home Page at:
>oo .--. oo .--. oo .--.
> \\(____)_ \\(____)_ \\(____)_
> `~~~~~~ `~~~~~~ `~~~~~~
José H. Leal, Ph.D.
Director, The Bailey-Matthews Shell Museum
Editor, The Nautilus
P.O. Box 1580
Sanibel Island, FL 333957 USA
(239) 395-2233; fax (239) 395-6706
"But fit the facts together in any other way and you get more nonsense
instead of less."
Travis McGee in "The Green Ripper," as told to John D. MacDonald.