help on determination of Praxillella and Clymenura

[Barbara Mikac]

Dear colleagues,

Can you advice me how can I determine Praxillella species based only on
the front part of the animal containing the head (thus it's not possible
to count the number of chaetigers). Sometimes I also have only pygidium,
but then usually without the front part. In the Adriatic Sea there
should be present: P. affinis, P. gracilis, P. praetermissa and P.
lophosetosa. P. gracilis should be easy to determin because it should
have distinctly elongated palpode on the prostomium. P. affinis should
have ocelli and P. praetermissa not. But what about P. lophosetosa? Are
the characteristics I mentioned above sufficient to distinguish the
species anyway?

I also have a problem to determine Clymenura clypeata and C. tricirrata,
that could be both potentially found on the stations I am working on.
It's quite easy when I have the pygidium, because if it has muscular
ring with three cirri originating from it, I know it's C. tricirrata. On
the other hand if it only has a muscular ring forming a pygidial plate
and an anal cone with a well developed ventral valve (Garwood, 2007) I
know it's C. clypeata. Most of my animals unfortunately lack the
posterior part/pygidium. Is there some way to distinguish two species
based on the front part of the animal?

Thank you very much for your help!

Barbara

________
Barbara Mikac, M.Sc.
Marine Research Centre
Rudjer Boskovic Institute
G. Paliaga 5
52210 Rovinj
Croatia
   

_______________________________________________
Annelida mailing list
Post: Annelida@...
Help/archive: http://www.bio.net/biomail/listinfo/annelida
Resources: http://www.annelida.net

[Geoff Read]

Those interested who don't know of Garwood (2007) can get it at:

http://www.nmbaqcs.org/scheme-components/invertebrates/literature-and-taxonomic-keys.aspx

Barbara,

This is not a part of the world I am experienced in but I can make some initial comments. If Garwood's nice indications for id'ing ant or post ends of (British Isles) maldanids don't get you an id then it probably can't be done. Pygidiums can be quite distinctive, and lacking them one can struggle.

I don't know much about Praxillella. lophosetosa (a lapsus, actually lophoseta(?), originally apparently Clymene lophoseta Orlandi, 1898), and while WoRMS currently has an entry for that combination, another entry places it as a synonym of P. affinis. I do not know who made the synonymy or whether it is accurate, without doing further investigating, but it may partly originate from Hartman's catalogue (p.454), and she most likely would have got it from somewhere else. Unfortunately, as with all her placements,  such source information, which would be hugely useful today, was not included in the catalogue - it may have existed only in her head or on an index card somewhere.

http://www.marinespecies.org/aphia.php?p=taxdetails&id=130322

Geoff

>>> On 20/10/2009 at 10:20 p.m., Barbara Mikac <barbara.mikac@...> wrote:
> Dear colleagues,
>
> Can you advice me how can I determine Praxillella species based only on
> the front part of the animal containing the head (thus it's not possible
> to count the number of chaetigers). Sometimes I also have only pygidium,
> but then usually without the front part. In the Adriatic Sea there
> should be present: P. affinis, P. gracilis, P. praetermissa and P.
> lophosetosa. P. gracilis should be easy to determin because it should
> have distinctly elongated palpode on the prostomium. P. affinis should
> have ocelli and P. praetermissa not. But what about P. lophosetosa? Are
> the characteristics I mentioned above sufficient to distinguish the
> species anyway?
>
> I also have a problem to determine Clymenura clypeata and C. tricirrata,
> that could be both potentially found on the stations I am working on.
> It's quite easy when I have the pygidium, because if it has muscular
> ring with three cirri originating from it, I know it's C. tricirrata. On
> the other hand if it only has a muscular ring forming a pygidial plate
> and an anal cone with a well developed ventral valve (Garwood, 2007) I
> know it's C. clypeata. Most of my animals unfortunately lack the
> posterior part/pygidium. Is there some way to distinguish two species
> based on the front part of the animal?
>
> Thank you very much for your help!
>
> Barbara
>
> ________
> Barbara Mikac, M.Sc.
> Marine Research Centre
> Rudjer Boskovic Institute
> G. Paliaga 5
> 52210 Rovinj
> Croatia

NIWA is the trading name of the National Institute of Water & Atmospheric Research Ltd.

_______________________________________________
Annelida mailing list
Post: Annelida@...
Help/archive: http://www.bio.net/biomail/listinfo/annelida
Resources: http://www.annelida.net

[Lovell, Larry]

-----Original Message-----
From: Lovell, Larry
Sent: Tuesday, October 20, 2009 2:37 PM
To: 'Barbara Mikac'; Polychaete mailing list
Subject: RE: [Annelida] help on determination of Praxillella and
Clymenura


Barbara,

Try staining your anterior fragment specimens in an ethanol solution of methyl green.  A solution dark enough to still see the animals in the stain should work well, too dark and you will have a hard time retrieving small specimens.  Or you can hold a specimen with your forceps and submerge it into the solution and hold there for 5-10 seconds or longer if necessary.  Place the specimen in fresh EtOH to destain yielding a pattern that will persist for several hours to several days.  The MG stain will eventually fade completely (some specimens/species may take much longer).  Maldanid species can have very specific methyl green staining patterns that can be used top ID incomplete specimens.  Stain a few of your voucher specimens for which you have a positive identification to establish the staining patterns for your known species and work from there for the fragmented specimens.  If there are 10-12 setigers present (sometimes fewer), that can usually be enough to tell pattern d!
 ifferences.  There will be thoracic and abdominal patterns.  The methyl green is reported/thought to stain mucous secreting glandular areas.

As an example, I can send (sent to Barbara) staining patterns of two local southern California species, Praxillella pacifica Berkeley 1929 and Euclymeninae sp A SCAMIT 1987, a provisional species. Credit goes to Kelvin Barwick, OCSD for the images.  PDF's of the images did not go through to Annelida (as expected), please request them from me if you would like them.

Methyl green staining patterns are useful taxonomic characters in other several other polychaete families:  especially the Maldanidae (Green 1987, 1991, 1997), Capitellidae (Green 2002; Warren et al 1994, Blake 2000), Cirratulidae (Blake 1996, 2006; Dean & Blake 2009; Doner & Blake 2009), and Sabellidae (Tovar-Hernandez 2007).  

Hope this helps.

Larry

Lawrence L. Lovell
Biologist II
Ocean Monitoring Research Group
County Sanitation Districts of Los Angeles
24501 S. Figueroa St.
Carson, CA 90745
[phone]  X-5613 office
[phone] fax
llovell@... <mailto:llovell@...>

-----Original Message-----
From: annelida-bounces@...
[mailto:annelida-bounces@...]On Behalf Of Barbara Mikac
Sent: Tuesday, October 20, 2009 2:21 AM
To: Polychaete mailing list
Subject: [Annelida] help on determination of Praxillella and Clymenura


Dear colleagues,

Can you advice me how can I determine Praxillella species based only on
the front part of the animal containing the head (thus it's not possible
to count the number of chaetigers). Sometimes I also have only pygidium,
but then usually without the front part. In the Adriatic Sea there
should be present: P. affinis, P. gracilis, P. praetermissa and P.
lophosetosa. P. gracilis should be easy to determin because it should
have distinctly elongated palpode on the prostomium. P. affinis should
have ocelli and P. praetermissa not. But what about P. lophosetosa? Are
the characteristics I mentioned above sufficient to distinguish the
species anyway?

I also have a problem to determine Clymenura clypeata and C. tricirrata,
that could be both potentially found on the stations I am working on.
It's quite easy when I have the pygidium, because if it has muscular
ring with three cirri originating from it, I know it's C. tricirrata. On
the other hand if it only has a muscular ring forming a pygidial plate
and an anal cone with a well developed ventral valve (Garwood, 2007) I
know it's C. clypeata. Most of my animals unfortunately lack the
posterior part/pygidium. Is there some way to distinguish two species
based on the front part of the animal?

Thank you very much for your help!

Barbara

________
Barbara Mikac, M.Sc.
Marine Research Centre
Rudjer Boskovic Institute
G. Paliaga 5
52210 Rovinj
Croatia
   

_______________________________________________
Annelida mailing list
Post: Annelida@...
Help/archive: http://www.bio.net/biomail/listinfo/annelida
Resources: http://www.annelida.net

_______________________________________________
Annelida mailing list
Post: Annelida@...
Help/archive: http://www.bio.net/biomail/listinfo/annelida
Resources: http://www.annelida.net

[José Eriberto Assis]

Dear Dr. Barbara

 

I have been work with Madanids - Phylogenetic Analysis of the Maldanidae Polychaeta Annelida, in the thesis to obtained the title of master, and I had some problems with some species without one the parts. For the Maldanids is very hard to idetifly only anterior or posterior end. If you have many specimens you can identifly to compare to specimens. In relation to the Praxillella and Clymenura both are  very hard becouse the main diferences consist in the pygidium. You can make draws of the uncinus and chaeta, and pheraps  you can to identifly to species. The problem also consist in that the description some species yet insuficient to make to compare. However, good luck.

Best wishes

Eriberto De Assis

On Tue, Oct 20, 2009 at 6:20 AM, Barbara Mikac <barbara.mikac@...> wrote:

Dear colleagues,

Can you advice me how can I determine Praxillella species based only on
the front part of the animal containing the head (thus it's not possible
to count the number of chaetigers). Sometimes I also have only pygidium,
but then usually without the front part. In the Adriatic Sea there
should be present: P. affinis, P. gracilis, P. praetermissa and P.
lophosetosa. P. gracilis should be easy to determin because it should
have distinctly elongated palpode on the prostomium. P. affinis should
have ocelli and P. praetermissa not. But what about P. lophosetosa? Are
the characteristics I mentioned above sufficient to distinguish the
species anyway?

I also have a problem to determine Clymenura clypeata and C. tricirrata,
that could be both potentially found on the stations I am working on.
It's quite easy when I have the pygidium, because if it has muscular
ring with three cirri originating from it, I know it's C. tricirrata. On
the other hand if it only has a muscular ring forming a pygidial plate
and an anal cone with a well developed ventral valve (Garwood, 2007) I
know it's C. clypeata. Most of my animals unfortunately lack the
posterior part/pygidium. Is there some way to distinguish two species
based on the front part of the animal?

Thank you very much for your help!

Barbara

________
Barbara Mikac, M.Sc.
Marine Research Centre
Rudjer Boskovic Institute
G. Paliaga 5
52210 Rovinj
Croatia


_______________________________________________
Annelida mailing list
Post: Annelida@...
Help/archive: http://www.bio.net/biomail/listinfo/annelida
Resources: http://www.annelida.net

--
Msc. JOSÉ ERIBERTO DE ASSIS
Universidade Federal da Paraíba
Centro de Ciências Exatas e da Natureza
Departamento de Sistemática e Ecologia
João Pessoa, Paraíba, Brasil.
CEP: 58051-900.
e-mail: eri.assis@...
(55) 83 - 8889-8791 (celular/mobile)
Currículo lattes: http://dgp.cnpq.br/buscaoperacional/detalheest.jsp?est=4531682067639497


_______________________________________________
Annelida mailing list
Post: Annelida@...
Help/archive: http://www.bio.net/biomail/listinfo/annelida
Resources: http://www.annelida.net