Thursday, February 23, 2012

Names, Names, Names!

At the last EPOS meeting, before the main talk, the speaker (Hendrelien Peters) gave an overview of some of the craziness around orchid names and how they keep changing at the moment, and usefully, how to wade through the morass to the right name for your plants.

If you're "in" the orchid world, no doubt you'll be familiar with the upheavals in plant names, if you're not, it's kind of interesting (not to mention frustrating), so here's what I recall of the topic, plus some useful tools. I sit right in the middle between the two camps - the hobbyists that don't like change, and the taxonomists that want to get it right, even if it's a bit annoying - I spent some time as a taxonomist-in-training, so I'm sympathetic to that, but it's quite frustrating to find many of the names you've painstakingly learnt have changed.

First up, the useful tools. It's generally a good idea to know what your plants are called, and keep this up to date, particularly if you have any intention of showing your plants, and especially if you intend to breed them. There are two notably useful online tools for this, the World Checklist of Selected Plant Families (which conveniently for our purposes includes the Orchidaceae) and the International Orchid Register.

WCSP website
First up, let's deal with the simpler case of natural orchid species . Kew maintains a World Checklist of Selected Plant Families at http://apps.kew.org/wcsp/home.do. Here, you can figure out what the correct current name of a species is (both genus and specific epithet), barring human error. (NB: This will not work with intergeneric hybrid "genus" or grex names; this database deals only with natural species). Take for example Sophronitis coccinea, a pretty, miniature red Cattleya Alliance plant that is prominent in the background of many "Mini Catts". Type Sophronitis coccinea into the box and click Find Name. This returns a list of several options, including the species and several varieties. You'll note none of them are in bold, which denotes a currently valid name (that is, the general consensus of plant taxonomists agrees that constitutes the "correct" name of a species). Next, click on the species you want - the first one for Sophronitis coccinea. This will then take you to a page that lists all the information about that particular species. You'll note that Sophronitis coccinea is currently considered a synonym for Cattleya coccinea which is the currently valid/accepted name for this plant. If you'd like to see what this little plant looks like, check out this IOSPE page. You'll note they still have it as Sophronitis - either they disagree or they haven't gotten around to updating it!




Results for Sophronitis coccinea
There are a couple of other useful functions. You can use wildcards to figure out something you've forgotten or aren't sure of the spelling for - if you're sure of the Genus, but not the specific epithet, just put the genus in and it will list every plant (valid or otherwise) described in that genus - look through the list for the one you want. If even the genus is uncertain, try a few letters with a * character. For example, pretend you're looking for Bulbophyllum rothschildianum, but you're not sure of the spelling. Try searching for Bulb* roth* and you'll get there! If you use the Advanced Search, you can check just the family Orchidaceae, which may be handy to speed up your hunt.

Many, if not most of the orchids people grow are hybrids between various orchid species. Most have been given variety ("grex") names. Many hybrids are even made and registered between different genera of plants, so you end up with what are called "intergeneric hybrids"; these are given a new "Genus" name - there are lots of these (78 pages and counting...), and a list is maintained by Kew here. Most of these are also given abbreviations, because writing out "Brassolaeliocattleya" gets tedious when you're labelling hundreds or thousands of plants, so there is an accepted abbreviation for pretty much every orchid genus (and intergeneric) - for example, "Brassolaeliocattleya" is Blc. If you're trying to work out what a particular abbreviation is, just search that page for the letters, or use the abbreviation document - http://www.rhs.org.uk/Plants/Plant-science/Plant-registration-forms/orchidabbrev. One of the effects of the taxonomic shake-ups is that these intergeneric hybrid "genera" change; some become invalid (because if genus X is subsumed into genus Y and intergeneric genus Q was X crossed with Y, then Q is no longer needed). Simple intergenerics are usually two or three genus names mashed together (portmanteau); after a while though, this gets unwieldy and people invent new names. Another listing is maintained by Jerry Bolce in Canada 2011 version here; 2014 version here. This is more up-to-date than the Kew one, which seems to have last been updated in 2005. This one by OrchidsAustralia is also quite good.

I was looking through that list for Iwanagara and couldn't find it. Why? Because as BrooklynOrchids tells us, Iwanagara is Cattleya x Caularthron x Guarianthe x Laelia x Rhyncholaelia x Sophronitis and several of those genera have been subject to big taxonomic shake-ups. Iwanagara Appleblossom is a fairly common plant. What is it called now? Now we turn to the International Orchid Register, http://apps.rhs.org.uk/horticulturaldatabase/orchidregister/orchidregister.asp (what an easy URL to remember... I usually just google it!).

International Orchid Register Search
Iwanagara is no longer valid, so we can't search using that, but we can use Appleblossom. So, click on Grex Name Search, leave the Genus blank and put Appleblossom into the second box. And...
Three hits for Appleblossom. We can discount Dendrobium right away. But is it now Jackfowlieara or is it Rhycholaeliocattleya? Click on each one to find out. When we click on Jackfowlieara Appleblossom, the page tells us that Iwanagara is a synonym. Bingo. Iwanagara Appleblossom is now Jackfowlieara Appleblossom. I next tried to find out what constitutes a Jackfowlieara, but the RHS site did not list it in their list of intergeneric names - but Jerry's list does. Jackfowlieara (Jkf.) = [Cattleya x Caularthron x Guarianthe x Laelia x Rhyncholaelia] What's missing? Sophronitis, which as we saw earlier, has been collapsed into Cattleya! If you're searching for something uncertain, you can use % as a wildcard at the front, or leave the back end off (try searching for Apple and then %ssom).

So hopefully you now have the tools to undertake your own plant label detective work!

But what is driving all this change? Are plant taxonomists sitting in their labs trying to make our lives as difficult as possible? Are they being foolish? Read some of the rants about name changes online and you might come to think that plant taxonomists are terrible, terrible people!

In fact, the taxonomists are trying to follow best practice in phylogenetics and systematics in making sure that the names plants have accurately reflect the relationships and evolutionary history between different plants. Biology is messy, and it can be quite challenging to separate out two species, let alone decide what is related to what and how closely. In the past, all such studies have relied entirely on what could be seen and measured - shapes, colours, sizes and that sort of thing. Modern science has placed at our disposal genetic tools that let us examine in unprecedented detail just how closely related various plants are to each other by examining their DNA. Hobbyists, of course, still rely on what they can see and measure - very few people have PCR machines and sequencers at home...

Essentially, with these new tools, it has been discovered that old relationships are wrong - sometimes we've been too zealous in assigning genus names (Cattleya and Sophronitis are too similar to be "worthy" of splitting) or we've been fooled by somewhat superficial similarity in form and "lumped" groups, which are then split apart. Laelia is another casualty of the "name wars"; many of them have moved across to Sophronitis - and then Cattleya, leaving relatively few species as Laelia!

A summary of the major changes:
  • Sophronitis = Cattleya
  • Laelia are now mainly Cattleya except a few species from Mexico
  • And whilst many things have been moved into Cattleya, others have been moved out! Quite a few Central American "Cattleyas" have been moved into Guarianthe.
  • Schomburgkia have been moved into Myrmecophila or Laelia
  • Odontoglossum are all Oncidium
  • Encyclia has seen a lot of things hived off. 
  • Here is a good overview of the Cattleya Alliance changes.

For a long time, the RHS orchid register didn't recognise Rhyncholaelia digbyana, keeping it as Brassavola digbyana. This has fairly significant repercussions as this species is quite important in Cattleya Alliance breeding - for example, most Blc. are probably not!

As for their impacts on your plant labels, this PDF is a pretty handy list for plants with Sophronitis and Laelia in their ancestry! Australian orchid genus name changes are extensively covered here. Just wait until the taxonomists sink their teeth into the mega-groups like Dendrobium and Bulbophyllum, and perhaps some of the Pleurothallids!

Ultimately, your best bet is probably to put the grex name (without the genus) into the search engine and figure out where it has been pigeon-holed for the time being. I have plants affected by this - my Slc. Kagaribi Dawn is now Cattleya Kagaribi Dawn. My Lc. Tropical Treat is now Cattlianthe Tropical Treat and so on! I don't have many Cattleya Alliance plants, so it's not too frustrating, but those with big collections of "Cattleyas" are probably banging their head against the desk next to a huge pile of blank labels right about now. If you have the software program OrchidWiz, it tends to be quite up to date, but also works with the old names, which is very handy!

If you're interested in learning more (this post is already quite lengthy), much of the work is done using the ITS ribosomal RNA region; this is roughly equivalent in usefullness to the COI mitochondrial DNA used in separating animal species. Although plants have COI, it evolves/mutates much more slowly than in animals, so is less useful in studies. One eventual hope is we'll have "barcode scanners" that can identify species by genetic markers alone.

Once you get into learning about how these decisions are made, and discover the fact that quite often (at least it's the case in animals) the people that make sweeping changes are molecular biologists with no traditional taxonomic training at all, you can see why you can have flaming arguments at systematics conferences, and perhaps why there can be so much flip-flopping! On the other hand, a surprising amount of taxonomy goes on "gut feel" and years of familiarity with a group (which perhaps explains why some keys are so impossible to use. What is "moderately long" when you've only ever seen one example? If you've measured hundreds of them, you'll know "moderately long" when you see it, but us noobs who haven't spent 30 years studying that genus? No...). Another problem of course is that the datasets are incomplete - if we had comparable sequences of every one of the ~30,000 species of orchids, it might be possible to create the One True List of Names, but that's a long way off - in the interim, the only constant is change!