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Posted: Feb 12 2012

Rissoina angeli Espinosa & Ortea, 2002, R. striatocostata (d'Orbigny, 1842)                                                   Page 1 of 2

This is a very long and complicated presentation with multiple galleries.  Be sure to scroll down and see it all.

Here are the applicable parts of Rolán, E. and A.A. Luque, 2000. The subfamily Rissoininae (Mollusca: Gastropoda: Rissoidae) in the Cape Verde Archipelago (West Africa). Iberus 18: 21-94.

2/12/2012 Posted on Conch-L:

"Rissoina angeli Espinosa & Ortea, 2002
Rissoina striatocostata (d'Orbigny, 1842)

R. striatocostata became an invalid name and was replaced with R. angeli. We are as yet a bit uncertain about the naming and distribution of shells similar to the one assigned the name R. angeli. We would like to hear from those with specimens similar to R. angeli (with the spiral cord in the center of the first 1-3 teleoconch whorls) collected in the Florida/Caribbean area."

The following discussion ensued:

Wed 2/15/2012 11:06 AM.
Marien Faber noted:

"Rissoina striatocostata may be a synonym of R. decussata (and I am not so sure about that) but Espinosa & Ortea too easily dismissed "Rissoina afinis [sic] (C. B. Adams, 1850 [sic])" = Rissoa affinis C. B. Adams, 1845. If in doubt about R. striatocostata then use R. affinis for this species. Rissoina angeli is a subjective junior synonym."



Following are the original descriptions/illustrations of three of the shells Marien mentions and a direct comparison of them (we're still seeking a good image of the type material for R. angeli):

Wed 2/15/2012 1:38 PM. Harry Lee asked:

"Dear Marien (+ Marlo et al.),

Did you (re)photograph that rather well-preserved holotype of the C.B. Adams species (affinis) during your December visit to the MCZ?

I have been struck by its similarity, as depicted in Clench and Turner (1950: pl. 34, fig. 5) to Colin's Rissoina sp. A (Redfern, 2001: pl. 16, figs. 138). The latter appears to differ from the concept of R. angeli held by most of us."

Wed 2/15/2012 2:16 PM. To which
Marien replied:

"yes, I did take a few pictures. I will send

you the images privately. I did not

compare it to Colin's specimens yet.

I have a few fc pictures (made 12 years

ago) of R. striatocostata too, the single

BM(NH) type, in poor and rapidly

deteriorating condition."

Marien provided the adjacent photos.


2/16/2012. Harry then commented:

"Dear Marien, Marlo, and other marine microgastropod mongers,

Marien sent me some very fine images of the

holotype mentioned below. With his permission

I then forwarded it to Colin Redfern, who made

a comparison with his species 138.

I agree with Marien that Rissoina angeli, the

shells on Marlo's webfeature, and Rissoa affinis

of C.B. Adams are a single species.

Colin believes his species 138 is distinct from

the C.B. Adams taxon, and I have no reason to

dispute this call.*

Like I said; it doesn't get any better!

 

 



* Its identity and that of Rissoina striatocostata d'Orbigny, 1842 [note lack of parentheses] rests on the determination by Espinosa and Ortea since neither the figure of the type nor text of the original description is diagnostic. The state of the d'Orbigny shells, particularly of the tiny ones, in the NHMUK (erstwhile BM[NH]) is said to be a clinical example of catastrophic Byne's Disease for over a century."

Note: NHMUK = Natural History Museum United Kingdom . The NHMUK was originally part of the British Museum (BM) founded in 1753, the first national public museum in the world. By act of Parliament in 1963, the Natural History Museum gained its own board of trustees and became fully independent of the British Museum.


2/16/2012. 
José H. Leal, Director and Curator The Bailey-Matthews Shell Museum nored:

"So it seems that R. affinis will be the name to

use for the SW Florida taxon, then.

I illustrated another species in this particular

group of “striatocostata”-like rissoinines in my

1991 book-dissertation on Brazilian oceanic

island gastropods. I used “Rissoina sp. 1” for

that species, mentioning that it was called

R. decussata (Montagu, 1803) by Rios in the

several installations of his Brazilian shell books.

Since I’ve been away from rissoine research (or

cured from rissoinophyly!) since the late 1980s,

would someone (Harry? Marien?) know anything

new about the identity of that species (I am

assuming that you have copies of the book

for consultation.)"

2/16/2012.  Harry then expounded:

"Dear José et al.,

Of course I have your book; to lack it would be tantamount to malpractice of rissoininophily.

Before getting to your species, let me offer a few additional thoughts on the identity of Rissoina striatocostata d'Orbigny, 1842.

Gary Rosenberg takes this position on Malacolog 4.1.1 http://www.malacolog.org/search.php?nameid=1996 "Rolán & Luque (2000) noted that a [my emphasis] syntype of R. striatocostata was conspecific with one of R. decussata, but other authors e.g., Jong & Coomans (1988) have considered the species distinct. They are treated as separate species here pending a lectotype designation."

You (1991: 75) reported "the examined syntypes of R. striatocostata (d'Orbigny Cuba Collection, BMNH 1854.10.4.209; 2 shells) have straighter shell profile, lack the paired spiral cordlets on the middle of the first teleoconch whorl, and have multispiral protoconchs, instead of the large, paucispiral one in this species." This observation removes R. angeli from the consideration.

Although I don't have access to the Rolán and Luque paper, it appears to me that your independent [and earlier?] examination included the only extant syntypes. Thus it may be unnecessary to lectotypify a syntype. I'll Cc this to Drs. Rolán and Rosenberg in hopes of clarification. I recall that Marien Faber was somewhat uncertain of the identity of the type material, and I think he has taken a peek at it. In any event, lets consider R. striatocostata and R. decussata synonymous for the moment.

Your species (Leal, 1991: 75; pl. pl. 8, figs. I-L) has a

teleoconch very similar to that of Colin's species 138,

Marlo's shells (first presented above), R. angeli Espinosa

and Ortea, 2002 (142; fig 1A), the holotype of Rissoa

affinis C.B. Adams, 1845 as revealed in the fine

photographs taken on 12 Dec., 2011 by Marien, and the

Sanibel shell depicted at the BMSM website (see

adjacent screen  shot below).  Even though yours is the

only SEM of this assortment, the conchological details

are laudably well-depicted in all these instances. While

the protoconchs of the latter four taxa are very similar

(2-3 whorls, small nucleus, broadly conical), yours and

Colin's differ from them and each other. As you pointed

out (Leal, loc. cit.), the Brasilian seamount shell has a

large paucispiral protoconch, which distinguishes it

from all these contenders (Colin's is another story).

Short version, I don't think we can give your shell a name.

I am struck by the analogous situation with the Phosinella you discovered in the seamount fauna; see the R lower corner at http://www.jaxshells.org/88ff11.htm as well as the Folinia sp. cited by Marien minutes ago. Each has uncharacteristic lecithotrophic development and may have evolved atop (or retreated to) these seamounts.

Espinosa, J. and J. Ortea, 2002. Descripción de cuatro nuevas especies de la familia Rissoinidae (Mollusca: Gastropoda). Avicennia 15: 141-149.
Leal, J.H., 1991. Marine prosobranch gastropods from oceanic islands off Brazil. Backhuys, Oegstgeest, Netherlands, x + pp. 1-418 incl. 22 pls.
Rolán, E. and A.A. Luque, 2000. The subfamily Rissoininae (Mollusca: Gastropoda: Rissoidae) in the Cape Verde Archipelago (West Africa). Iberus 18: 21-94."

2/17/2012. José replied:

"Thanks so much for your account. Oops, it seems like I there is enough material there in those stashes to justify a return to substance abuse of the rissoinophilic type. I will scan my old SEM (4x5) negatives and post-them for the sake of illustrating your points. (Marlo has asked for some illustrations, and I will send them to him to.)

Best wishes and thanks for the thoughtful response!"

The above communications all took place on Conch-L. There then followed a series of email correspondences among a group of “marine microgastropod mongers” and “Rissoinophiles,” including:

Marlo F. Krisberg, instigator and administrator of Let’s Talk Seashells
Harry Lee, Citizen Scientist
Marien Faber, Netherlands
José Leal, Director and Curator, Bailey-Matthews Shell Museum
Colin Redfern, author Bahamian Seashells 2001
Emilio Rolán, author numerous articles focused on Caribbean micros.

Following are pertinent excerpts of the correspondence with photo images as appropriate:

2/19/2012.
Harry commented as part of an email:

“The "description" of Rissoina striatocostata is general and ambiguous. It could fit either the Montagu species (R. decussata) or R. angeli. (as well as a few others).” “None of the authorities whose work I've cited have used the original description as instructive. The identity of Rissoina striatocostata rests on the interpretation of the type material. There are two interpretations (it is distinct or it is not), but I, for one, have not seen evidence to support that of Emilio Rolán (Rolán E. & Luque Á.A. 2000).

Any of our little taxonomic cabal is fully within his rights to call Rissoina striatocostata and R. angeli synonymous based on the syntype figure Marien provided us.”

Comment by
Marlo:  As note above in Harry’s post of 2/16/2012, José (1991: 75) reported "the examined syntypes of R. striatocostata (d'Orbigny Cuba Collection, BMNH 1854.10.4.209; 2 shells) have straighter shell profile, lack the paired spiral cordlets on the middle of the first teleoconch whorl, and have multispiral protoconchs, instead of the large, paucispiral one in this species (José’s shells from Brazil)." Emilio had also failed to distinguish spiral cordlets and considered the syntypes conspecific with R. decussata. Marien’s photos above of the best preserved syntype of R. striatocostata do not sufficiently display this character. So, we’re confronted with a description that is “general and ambiguous” and type material apparently so degraded that it is no longer useful. It seemed to me (at this point in the discussion) that there is a shell to which the name R. striatocostata applies, but it is uncertain to which of the several similar ones with spiral cordlets on the middle of the first teleoconch whorl it does indeed apply. Over the next days we explored this dilemma further.

My dilemma was that apparently José and Emilio had both failed to discern spiral cords on the syntypes of R. striatocosotata and additionally Emilio had seemingly synonymized the syntypes with R. decussata. Espinosa and Ortea (who have worked with and are quite familiar with Emilio's work) apparently, but not explicitly, relied on Emilio's synonymization to conclude that no name existed for a Rissoina with the spiral cordlets, failed to discover or address prior pertinent literature (at least Adam's affinis, José's Rissoina sp. 1, and DeJong & Coomans), and created a new name - R. angeli). So, I sent a quiry to Harry:

February 18, 2012  "I guess I don't understand. If D&C in 1988 used the name R. striatocostata in the belief that their shells fit the description, then how would their shell be considered "distinct" if it later turned out that the description they relied upon was erroneous and did not fit the syntype, and the syntype was actually R. decussata. That would leave D&C's shell without a name. But for Espinosa and Ortea, if no one else has named a shell with the "salient feature" of a spiral cord on the first 1-3 teleoconch whorls, how can the shells we're discussing not be R. angeli? I understand that the simple presents of the spiral cords does not mean all with them are R. angeli, but until someone publishes a study distinguishing and demonstrating valid real differences, why not apply R. angeli. (Unless it can be demonstated Espinosa and Ortea erred and, as Marien feels, R. affinis applies.)" And, "If José found that the syntypes of RS did not fit the description for RS, then doesn't that validate Emilio's finding in 2000 and mean the shells with spiral cord on the first 1-3 teleoconch whorls were without a name?"

February 19, 2012.
Harry replied:

"You're making this more difficult than it needs to be.

José's comparison was between his species and the syntypes of Rissoina striatocostata..." "He appears to have erred in not mentioning the peripheral keel on the early teleoconch of the better-preserved of the two syntypes."

"The only real anomaly in this whole analysis is Emilio Rolán's synonymizing these syntypes with Helix decussata Montagu, which has been consistently identified as a shell quite distinguishable from that in Marien's image (of R. striatocostata).

2/19/2012.
Marlo replied:

"It’s not that straight forward for those of us less intimate and often struggling with the nomenclature and naming rules, Indeed, I do have to sit down with all of this in front of me and try to digest it again. If I understand Marien’s photos (of R. decussata), I agree they may be different from his photos of the syntypes of Rissoina striatocostata, but if Emilio is correct, the syntypes = R. decussata and the name R. striatocostata applies to nothing. So, then why can’t R. angeli be valid until someone proves otherwise? I agree that, as illustrated

in the adjacent scan, Emilio simply made a statement and his paper provided

nothing more. So, it’s weak."

2/19/2012. Harry:

"I thought you received Marien's photo's

yesterday, but now I see you didn't get them

until this afternoon.

Take a look at them and form your own opinion

about the accuracy of Emilio R's determination.

You now have some pretty authentic R. decussata

to which you can refer as well.

I have attached a photo of R. striatocostata from

Kice Island, Marco area, Collier Co., FL.

As you can see, the midwhorl spiral cord(s) is

effaced, but it's otherwise very close to the

better syntype and the shells you figure on LTS."

2/20/2012. Marlo wrote:

"Frankly, it is so effaced there could be doubt. However, it is almost identical to mine, esp. the protoconch. Don’t find the best preserved syntype photo adequate to make a judgment."

 

 

 

 

 

2/21/2012. Colin Redfern

provides images of his shell (pictured

above and adjacent):

2/21/2012. Marlo and Harry had sent inquiries to Emilio and on this date Emilio wrote:

"Dear Harry, dear Marlo

I have been in a small trip the last days. I have seen the polemic about the Rissoina species and so, I have thought to put in images the diagnosis of the species of this group I had from Raúl Fernández-Garcés and myself. First at all some explanations:

1- It is true that Rolán & Luque 2000 mentioned that the types of R. decussata and R. striatocostata seemed to be conspecific, but we were not studing the Caribbean Rissoina but African Rissoina. So, we had not present all the taxa and the types in BMNH probably were not in perfect conditions, so this is an afirmation which to be sure that it is true would need a better examination even at SEM of the type material.

2- The photographs we are now presenting with a name are not types, so they are those shells that Raúl and myself have considered corresponding with this taxon, but also this need confirmation.

3- Unfortunatly we have not any information about R. affinis except the figure of Clench & Turner (1950). So, we expect to get an imagen from the type in MCZ,

4- The images from Leal (1991) as sp 1 from Victoria Seamount may represent 1 or 2 new species.

At least these images can represent an initial aproximation to the species which have first whorls of teleoconch with only one or two alone spiral cords. I have more, which are waiting to be photographed and this will be information for the next week (approximatly)."

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In addition to the information on the adjacent

slide, Emilio also indicated that "This photo is

from material collected by Raúl in the type

locality. The holotype is in Cuba (no possible

to get it) but a paratype is in Tenerife

(Canarias)  and perhaps, if necessary, it is

possible to get it."

 

 

 

 

2/21/2012. On the same day

we heard from Emilio, Marien wrote about

another of his images:
 

After receiving Emilio's emal, Marlo wrote to Harry:

2/21/2012. "If I understand Emilio correctly, he has confirmed that his simple comment in Rolán & Luque 2000 cannot be taken as valid. And, since it is not, and Espinosa & Ortea relied upon it, then their naming is invalid."

February 21, 2012. 
Harry replied:

"Actually Espinosa and Ortea did not mention the Rolán and Luque paper (but they surely knew of the synonymy in it as the four of them have collaborated over the years). In fact Rissoina striatocostata was not even mentioned in the description. You could accuse them of being coy, but their name is available under the Code.

Their R. angeli, at least Emilio's concept of it (one of yesterday's SEM's), actually looks different from all the taxa we've been discussing."

22 Feb 2012.
Harry, regarding Emilio's photos of the Cuban shells):

"Dear Marlo and Marien,

These images depict Emilio's concept of what (gem specimens of) these two species look like. Nothing more. However, you can bet that he has given these determinations lots of thought."

"What's also of great importance and problematic, but can probably be settled, is if the NHMUK cotypes (the basis for the judgement by Rolán and Luque (2000: 26) and Exeter Museum shell(s) (Marien's images) are all genuine syntypes of Helix decussata Montagu, 1803 or if the only true type(s) are at one or the other institution. Thus far the only opinion on the matter is that of Marien (Exeter)."

2/22/2012.
Marien:

"if I recall correctly then the catalogue number used by Rolán & Luque is not an NHMUK number, but an Exeter Museum number; there are no R. decussata types in NHMUK.
I agree with the naming below (Emilio's SEM photos of Cuban shells), although the type specimens of R. striatocostata are poor. However, this is the same as R. affinis, and R. angeli. Then there is Colin's species, which, as far as I know, is nameless."


Although not previously mentioned another shell is about to enter this discussion. I am inserting photos of it here.

23 Feb 2012. Marlo inquired of Marien:

"If affinis Adams, 1845 was named after striatocostatus d’Orbigny, 1842, and if they are the same, why isn’t the former a junior synonym? What rule am I missing?"

2/23/2012.
Marien replied:

"If R. affinis = R. striatocostata then affinis is a junior synonym indeed.

Provisionally I have (valid name followed by junior synomyms):

1. R. striatocostata = R. affinis = R. angeli.


 

2. R. decussata = R. albida (this synonymy is doubtless)

3. Colin's species

but it could be:

1. R. affinis = R. angeli. (this synonymy is doubtless)

2. R. decussata = R. striatocostata = R. albida

 

 

3. Colin's species

The doubtful one, for me, is R. striatocostata, this based on the best extant type. But in my opinion it looks more like R. decussata and R. albida than to R. affinis. The description and type-figure, however, reminded more of R. affinis. But at the moment I do not have the type figure (thought I did, but I cannot find it)."

2/23/2012. Harry commented on

Marien's suggestion with his own

straw man:

"Dear Committee of five + me,

However, now that I look at a bunch of

shell images on the same screen, I'm

beginning to see Marien's point (below)

about the possibility of this nominal

taxon being a junior synonym of Helix

decussata Montagu as depicted in

Marien's SEM of the type. This would

confirm Emilio's 2000 perception. The

slightly distorted contour of the latter

whorls seems to be peculiar to

R. decussata. It's difficult to explain,

but I think most of you know what I mean here.

One problem with the Montagu species, at least as I have come to know it, is the great variation in size of apparent adults. Coupled with what appears to be allometric growth (spire looks more attenuated in larger shells), there can be difficulty in identification, especially of material (e.g., the "better" syntype [light photo by Marien] of R. striatocostata) with loss of structural characters.

Emilio's concept of R. angeli differs from the above three images, and all three differ from Colin's species and that of José. However this concept of R. angeli is close to Marlo's shell .... My lesser-quality shell from Kice Island (SW FL) is close to Marlo's. As with R. decussata, variation in size (and, of course, degree of wear) complicates diagnosis in this group of specimens.

 

 

 

 

Marlo: So here's my first straw man:

R. decussata + R. striatocostata + R. albida

R. affinis + R. angeli + Marlo + Harry

 

 

 

 

R. striatocostata of authors (and SEM's of Emilio and Marien):

possibly two species here

 

R. species of Leal

R. species of Redfern

2/29/2012. Marlo had sent all the shells presented in his above presentation to Emilio. On this date Emilio provided SEM photos of them with comments:

"I have made new photographs of Rissoina from Marlo. These are sent now. The problem is that (in my opinion) they do not clarify the situation: We have a lot of species with multispiral protoconch and the assignation to one or other taxon is only an individual decission. Only after the examination of all types available we could get a complete security about the separation.

I think that I will get the examination of the paratype of R. angeli in Museo de Ciencias Naturales of Tenerife. I will inform."

2/29/2012. Emilio forwarded SEM photos and descriptions of Raúl Fernández-Garcés' material collected in Cuba. Please do not reproduce these photos without first obtaining permission from Emilio or Raúl.

 

Emilio concluded with "We will continue."

Some more correspondence regarding R. angeli:

2012/2/26.
Marlo :

"Hi Emilio,

I have a poor photo copy of E&O’s paper with a very poor image of their R. angeli, Do you have any images of their type material. If not, how confident are you that Raúl’s material is indeed the same shell?"

2/26/2012.
Emilio:

"I have the issue of Avicennia with the desciption of R. angeli. Unfortunatly Espinosa & Ortea didnot use SEM photographs, so, the photo is not enough to consider which species is. Raúl saw the type material and he find the shell which sent me and he thought that it was the same species. But the most sure is to ask for the loan of the paratype in the Tenerife Museum.

To contact with Espinosa or Ortea is not useful because they only had two shells when the description was made and not more later."

3/8/2012. This date
Emilio provided his interpretation of the data we've compliled and presented it with several other species under the heading "The Rissoina species with planktotrophic* development in the Caribbean and close areas."

*larvae dispersed into the water and generally spend a fairly long period suspended and feeding in the water column."


Emilio commented: "I have thought about the problem of the Rissoina species and, after the examination the important material from Marien Faber, I have goten the following conclusions which I am sending you for study and discussion: the taxa are in older order, and this is only a scheme." "I have focussed the problem only in the planktotrophic species." "I have also one group of photographs from Marlo which must be placed in a name. But I prefer to wait for the R. angeli paratype."

Rissoina elegantissima (d’Orbigny, 1842) - (It may be Schwartziella)

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