Another new Corydoras species

[lfinley58]

Hello all, this is my first posting. I am happy to be on the forum. I have been laying low for a while. Thanks Dave R. for letting me know about it.

The new Copeia (2002, No. 4) arrived today and a new Corydoras description is included (by Marcello Britto and Ricardo Castro). The new species is designated as Corydoras difluviatilis and is described from the upper rios Parana and Sao Francisco of Brazil. It is noted to physically most resemble C. garbei. But the species is noted to be the most basalmost (primitive) member of the genus and it is obvious from the text that the authors at least considered placing it in another (new) genus. However, the authors feel in "...that the new species has a generalized appearance of a Corydoras, inclusion of the new species in a separate genus would lead to more confusion than clarification concerning taxon names. Thus, the more conservative course of action of the placement of the new species in Corydoras is the alternative favored here."

For those keeping up with new Corydoras descriptions and/or higher level taxonomic discussions regarding Aspidoras, Brochis, and Corydoras (as well as, according to the authors, an as of yet unnamed genus), this paper should be on the must read pile. I will also note that there are some interesting biological observations in the paper. Such info is most often, and sadly, lacking in most Corydoras (and related) descriptions.

Lee

[clothahump]

Great stuff Lee,

Is there anyway of reading the whole description? are there any photographs available?

[Coryman]

Hi Lee

Where can I obtain a copy of the paper and is there any images of live specimens published

Ian

[lfinley58]

Hello Ian and Clothahump - There is one b&w photo in the article. It is the preserved holotype and almost looks alive . I'd be happy to fire off a copy of the article. In that both of you are in the UK how about I send a copy to Ian and have him recopy and forward to C. This will save on the postage. Ian could you please email me your mailing address (to be sure) and I can put it in the mail on Monday AM.

Lee

[clothahump]

Sounds good to me Lee, thank you very much.
OK with you Ian.

[Coryman]

Lee

That would be fine, I tried looking for it on the web but kept comming to dead ends. Don't know where to look really?

Ian

[Jools]

Copeia: Vol. 2002, No. 4, pp. 1006–1015.

New Corydoradine Catfish (Siluriformes: Callichthyidae) from the Upper Paraná and São Francisco: The Sister Group of Brochis and Most of Corydoras Species
Marcelo R. Britto,a and Ricardo M. C. Castroa

a(MRB) Museu de Zoologia da Universidade de São Paulo, Cx. Postal 42594, 04299–970 São Paulo, São Paulo, Brasil; and (RMCC) Laboratório de Ictiologia de Ribeirão Preto, FFCLRP, Universidade de São Paulo, Av. dos Bandeirantes 3900, 14040–901, Ribeirão Preto, São Paulo, Brasil. (MRB) E-mail: mrbritto@ib.usp.br. Send reprint requests to MRB.


ABSTRACT



Corydoras difluviatilis, new species, is described from the upper rio Paraná and the upper rio São Francisco, Brazil. The new taxon differs from its congeners by three exclusive features: the posterior pectoral-spine serrations restricted to its proximal half, and the parapophyses of the fourth free vertebra reduced and separated from each other, not fused into a haemal arch. The new species has several plesiomorphic character states relative to the assemblage composed of Brochis and most Corydoras species, such as absence of contact between the supraoccipital and nuchal plate, reduction of the ossified portion of hypobranchial 2, and well-developed mesial expansions of the first and second infraorbitals, indicating its basalmost position within the genus.

Corydoras difluviatilis, espécie nova, é descrita para o alto rio Paraná e alto rio São Francisco. O novo táxon difere de suas congêneres por três caracteres exclusivos: o serrilhado posterior do espinho peitoral restrito à sua metade proximal, e as parapófises da quarta vértebra livre reduzidas e disjuntas, não fundidas em um arco hemal. A nova espécie apresenta vários estados plesiomórficos em relação ao grupo formado por Brochis e maioria das espécies de Corydoras, tais como ausência de contato entre o supra-occipital e a placa nucal, redução da porção ossificada do hipobranquial 2, e expansões mesiais do primeiro e segundo infraorbitais bem desenvolvidas, indicando sua posição basal dentro do gênero.



Manuscript Received by the Society 23 Oct. 2001
Manuscript Accepted 26 April 2002



Section Editor: S. A. Schaefer


© Copyright by The American Society of Ichthyologists and Herpetologists 2002

or visit http://apt.allenpress.com/aptonline/?re ... &page=1006


Jools

[Jools]

Hi Lee,

Nice to see you on the forum. Would this happen to be the fish?

<IMG SRC ="http://www.planetcatfish.com/jpg/callic ... ano''1.jpg">

I'm out on a limb at the moment but I _think_ it is from the right place, I can check with the photographer/collector (HG Evers).

Jools

[coelacanth]

I can get that article over here in the UK, and make copies from that if that would make it any easier.
Pete

[lfinley58]

Hello Jools and Pete - Regarding the photo posted by Jools: There is certainly a similarity, but also some differences from what I can see. There is a (color, I believe) photo of this new species that was published a while back in Ichthyological Explorations... I will check this out and go closely over the description in Copeia and see what I can come up with. I will make a post on this tomorrow as I will be away for most of today. It would be interesting in any case to know if H.J.E. has a locality for the fish in the posted picture.

Regarding Pete's post: If you have the new issue of Copeia at hand that would be good. If you have to track it down (interlibrary, etc.) it is no problem for me to mail it out to Ian tomorrow AM. My photocopier is one of my best purchases . Actually, it was Aline's idea and is a great business (and fun) tool.

Till tomorrow.

Lee