Neofinetia - now Vanda

[Roy]

I'm just waiting for them to suggest a change in Sarcochilus. They are classed as Vandaceous, as are Phalaenopsis and they inter breed. This blows the mind!!!!

[Ryan.Walsh]

Hello everyone, I know I'm new here and this thread is old but I felt that I could shed some light on this issue. I'm currently on the last semester of my Ph.D. in Biology, specifically studying Cypripedium candidum ecology and evolution. I'm a little disheartened to see the apparent despise for taxonomists (I'm not one) and thought I might be able to offer some explanations that may make you all a little less irritated at the frequent name changes.

As you all know DNA analysis has revolutionized Biology and in particular systematics. What many of you may not know is that the field is anything but it stasis, it is constantly improving and getting cheaper. Where 10 years ago it may have cost thousands of dollar to sequence a relatively small number of species for a very small section of their DNA (700-800 basepairs) today a sequence like this will cost orders of magnitude less (at last pricing a single sample is $5-10). With this drastic decrease in sequence costs, researchers are able to sequence larger numbers of species and larger swaths of DNA in each of these species. When scientists talk about sequencing DNA, most of the time they aren't talking about sequencing the entire genome but simply sequencing small sections that are evolutionarily informative. Most often these sections are within the nuclear, mitochondrial, chloroplast or ribosomal genes. Each one of these sections evolve at different rates and are informative at different levels (i.e. between individuals, genus, species, sub family etc.). Due to the decreased cost and increased ability to sequence scientists are able to create much more accurate phylogenetic trees which inform us to the evolutionary history of the organism. By lumping things into a genus or species we are explicitly stating that at some point in the past, these species shared a common ancestor and have since evolved from that ancestor. I can assure you taxonomists are not just doing this to annoy you, each correction has an evolutionary reason.

In the case of the Neofinetia to Vanda issue, this change was announced in a peer reviewed publication this year in the Journal Phytotaxa by Dr. Lauren Gardiner in the article "New Combinations in the genus Vanda (Orchidaceae)". I have access to this journal and article so I can summarize it here. Based on new molecular evidence, species in the genera Ascocentrum, Ascocentropsis, Christensonia, Eparmatostigma, and Neofinetia are being reclassified to the genus Vanda. This reclassification as well as information on the analysis will be published in the forthcoming Genera orchidacearum. The Neofinetia treatment in particular was done based on molecular data, ease of hybridization and prior classification. Neofinetia falcata was at one point correctly classified as Vanda falcata in 1854.

Hopefully this all makes a little more sense and you all don't think us scientists are evil . If you have any more questions please feel free to ask and I will answer them to the best of my ability.

[Brutal_Dreamer]

Thanks Ryan for this explanation.

cheers,
BD

[walingwaling]

Thanks Ryan,

that was very well explained and more of it is needed every time big changes are published. For me that's the main reason why this whole gap between KEW e.g. and growers/taxonomists is constantly growing.
I just wonder what will happen to all the observations done over more than a century, genera created, and sections to it, when it all falls back to one ancestor?
Is it really the right approach and let the hard evidence win over lots of visible differences within species and genera?
Evolution has shown a great deal of it's magic and here we are, lumping genera together based on certain DNA traits, so I'm not sure on which side I should stand on, possibly both, if it can work out.

Thanks again, for showing us the friendly side of an "evil" scientist, lol.

[Ryan.Walsh]

Ron, If you don't mind I would like to address your statement because it is something that is often brought up.

I just wonder what will happen to all the observations done over more than a century, genera created, and sections to it, when it all falls back to one ancestor?

One of the biggest debates that occurs among taxonomists are where to draw the line between genera. Of course if you continue to go back through evolutionary time many genera will be linked to a common ancestor, this is what we like to think of as subfamilies. The real debate is where to draw this line. Most agree that a well done taxonomic tree using numerous genetic markers, and if possible morphologies of both extant and extinct species is the best approach to classifying organisms. The problem with morphology, particularly with orchids, is that extinct ancestors are typically lacking. Orchids do not form woody secondary tissue that is typically preserved the best in the fossil record. Pollen can be useful but unlike typical flowering plants, orchids produce pollen in organized structures that don't lend to spreading around. Compare the amount of pollen produced by a ragweed plant to a typical orchid for example. What taxonomists today try to do is use all of the evidence available and then make genera delineations based on both the genetic data and common sense data such as similarities in structure and ability to interbreed. As I mentioned earlier this is exactly the reasons listed by Kew for making Neofinetia part of Vanda.

Another thing to keep in mind is that typically the genetic evidence isn't making a brand new discovery but rather providing support to a previous hypothesis. This can be demonstrated in the case of Neofinetia falcata. If we look at the synonyms for N. falcata we can see that a whole lot of scientists have published papers claiming this plant was in one genus or the other. As a starting point, the plant we know as N. falcata was originally described by Thunberg in 1784 as Orchis falcata. By taxonomic convention Thunberg will always be named as the first to describe the species typically by placing his name in either () or preceded by ex. Following Thunberg's original description the following people have published peer reviewed articles on the taxonomy of the plant placing it in one genus or another (dates in parenthesis):
Limodorum falcatum (Thunb.) Thunberg (1794). <-Yes you read this right, he disagreed with himself ten years later
Angraecum falcatum (Thunb.) Lindley (1821).
Oeceoclades falcata (Thunb.) Lindley (1833).<-Same with Lindley
Vanda falcata (Thunb.) Beer (1854)
Aerides thunbergii Miquel (1866).
Angorchis falcata (Thunb.) Kuntze (1891a).
Angraecopsis falcata (Thunb.) Schlechter (1914).
Finetia falcata (Thunb.) Schlechter (1918).
Neofinetia falcata (Thunb.) Hu (1925).
Nipponorchis falcata (Thunb.) Masamune (1934).
Holcoglossum falcatum (Thunb.) Garay & H.R.Sweet (1972).

So as you can see this really isn't a case of the genetic data swooping in and throwing out the morphological data. It's actually a case of the genetic data supporting one scientists morphological analysis over another. In this instance Beer actually had it right over 150 years ago and it was Hu who incorrectly assigned it to a new genus. Kew, believe it or not, is actually putting things back to the way they used to be