Cattleya

Finding

SITF has determined that there is insufficient evidence to invalidate the award to the Cattleya walkeriana 'Kathleen'. Many of the C. walkerianas currently in cultivation may probably be hybrids. There is no real good way to discriminate these walkerianas that may have intrusions of nobilior or loddigesii or others in any of the modern polyploid, line bred plants. The only way to accurately determine the species purity would be through genetic sequencing to determine the amount of intrusion of other species. Carl Withner, in Vol 1 of his series, described two types of Cattleya walkeriana, the first has bulb-like pseudobulbs (cylindrical) up to 15 cm and the other, which was originally C. bulbosa, had short, almost round pseudobulbs, darker flowers and was more symmetrical. Bill Rogerson sent SITF length measurements of several Cattleya walkeriana plants, including C. walkeriana 'Kathleen', they all measured less than 15 cm, so there is insufficient evidence of loddigesii in these, based on pseudobulb heights. Comparing other characteristics, there is insufficient evidence to overturn C. walkeriana 'Kathleen' or other awarded C. walkerianas of the same type, although whether they are or not "pure" species would have to be determined through sequencing.

Judging Center: Chicago JC

Award Number: 20252606

Award Date: April 12, 2025

Awarded As: FCC

It is my understanding that the Chicago JC just awarded an FCC to a Cattleya walkeriana and I have attached a photo to this email. I understand the award occurred yesterday and the owner is Bill Rogerson. I think the SITF might consider investigating this one a bit since it does not appear to be walkeriana, based on the size of the flowers, the circular and fully flared sidelobes, the white halo around the sidelobes, and a few other characteristics.

My suggestion is that this is actually a polyploid Brazilian Jewel (walkeriana x nobilior). All of the above characteristics can be found within really nice Brazilian Jewel and Mauro Rosim (well known Brazilian grower) has several great examples of this hybrid on his flicker site. I have posted a link for one of these below this paragraph. Notice the similarity to Kathleen in both flower shape (especially the flared sidelobes) and color. You might consider reaching out to Francisco Miranda and Harry Akagi here in the USA for their opinion. In Brazil, I suspect Mauro Rosim would be a great resource, as would Cesar Wenzel, among others.

https://www.flickr.com/photos/rosim/3974199805/

As you know, hybrid vigor can increase the size of flowers, which appears to be the case with Kathleen. Note statistics below:

- 10 most recent walkeriana AM/AOS average 10.4cm NS horizontal and 10.7cm NS vertical
o Kathleen is roughly 40% larger!
- 10 most recent nobilior AM/AOS average 10.2cm NS horizontal and 10.7cm NS vertical
- Only two Brazilian Jewel awards (both are from JOGA) measure 11.5cm NS horizontal and 11.5cm NS vertical
o Brazilian Jewel is the manmade hybrid of C. walkeriana x nobilior
o Neither is particularly nice but you can already see the flower size is noticeably larger than the walkeriana AM/AOS awards
- There is one award to Cattleya x mesquitae ‘Kao’ AM/AOS with dimensions of 10.7cm NS horizontal and 11.0cm NS vertical
o C. x mesquitae is the natural hybrid of C. walkeriana x nobilior
o This has a similar appearance to ‘Kathleen’ with white sidelobes flared in a circular manner and lavender segments
o Notice that this is also on the large size if compared with pure walkeriana or nobilior, despite it being a natural hybrid
It is my understanding that Kathleen is likely polyploid. I have an interesting example of a polyploid nobilior that is absolutely monstrous compared to a typical sized nobilior (link to three useful photos posted below this paragraph). My polyploid nobilior has parents of #1 x #2 from Francisco Miranda’s breeding and my plant was not treated for ploidy so it appears to be a natural polyploid. Notice that the size of the flowers on my polyploid (~14.6cm NS horizontal) are nearly the same size as Kathleen! Also notice that the slidelobes on my polyploid are very flared, which Francisco tells me is a normal characteristic of a polyploid nobilior. Typically, nobilior have sidelobes encircling the column and then flaring only at the tips. The third photo shows a comparison of the polyploid with a typical nobilior.

https://www.flickr.com/photos/isurus79/50850557693/in/album-72157632735884183
https://www.flickr.com/photos/isurus79/50851280201/in/album-72157632735884183/
https://www.flickr.com/photos/isurus79/50868080926/in/album-72157632735884183/

Kathleen appears to be a polyploid Brazilian Jewel based on the following:
- Enormous size totally dwarfing any awarded walkeriana
- Very distinct sidelobe shape with flaring appearing to form a circle, totally exposing the column, which is not characteristic of either nobilior or walkeriana
o Both species have sidelobes encircling the column with flaring at the distal end, though with somewhat different sidelobe lengths (nobilior is typically longer than walkeriana)
o Kathleen is nearly identical in color and shape to Brazilian Jewel grown by Mauro Rosim and also Cattleya x mesquitae ‘Kao’ awarded in Brazil
o The totally exposed column with extremely flared sidelobes could very well have come from nobilior, which exhibits both monstrous size and extremely flared sidelobes on polyploid plants

Also worth noting is that Kathleen is a selfing of the awarded plant Cattleya walkeriana 'Mark Trevor Ranum' AM/AOS. It is definitely worth investigating that plant also, which similarly looks like a Brazilian Jewel. If the SITF agrees that Kathleen is a hybrid, I can submit a similar SITF challenge for Mark Trevor Ranum.

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Learn more about the Cattleya genus