Dendrobium unicum and Dendrobium dickasonii, problem

[A G]

Hello! I would really like to know the differences between these two species?
Recently I have seen alot of pictures on swedish orchid forums which are labeled as D.dickasonii but looks alot like D.unicum. Same thing happens when you do a google search of D.dickasonii.

Can anyone please help me?

[Ray]

Looking at Jay Pfahl's Internet Orchid Species Photo Encyclopedia, they look totally different:

D. unicum: IOSPE PHOTOS

D. dickasonii IOSPE PHOTOS

[A G]

I agree with you Ray, but have a look at this picture from Gothenburgs botanical garden in Sweden:

http://www.neovita.com/orkideer/bild...51819.orig.jpg
(warning, large .jpg)

If you look down to the right you can see a D. unicum which is labled D. dickasonii (quite hard to see). It seems that several vendors here in Europe are selling D. unicum as D. dickasonii.

[cloudswinger]

Based on the descriptions in Jays site, the difference is that dickasonii has bigger flowers. One would hope that a botanical garden has made the effort to determine the difference. Did you talk to anyone there? They should be made aware if there is an error.

Also, I've noticed that the description of unicum in the dendrobium book I have states that the canes can be up to 2 ft long, which kind of matches the pictures, but other books, and Jays site has it as a miniature, which matches the plant I have. I don't have the book handy, otherwise I'd look up dickasonii.

[A G]

Sadly, it was not me who took that picture, but I think I´m going to mail them and ask.

Thanks for the help, Ray and Cloudswinger.