Orchids whose name begins with E
OR
Once upon a time there was a genus named Epidendrum
Moderator: Marilyn Light
January 12, 2005

The genus Epidendrum was, like many of those root genera, a once all-encompassing collection of somewhat similar orchids found growing on trees in the neotropics. The name was published by Linnaeus in 1759. Some of these orchids have resupinate flowers and some do not. Some have swollen pseudobulbs with a couple of leaves on top and some have long reed-like pseudobulbs that are leafy along most of their length. Some have round capsules and others capsules that are triangular in cross-section. Still, for a long time, they were mostly lumped together into a group called the epidendrums.

Lindley devised a way to separate sub-groups and then published a key to recognize 12 sub-groups (subgenera) in 1853. He subdivided the epidendrums according to a few basic characteristics including:

1) whether or not the lip was attached to the column;
2) whether or not the flowers arise from a spathe (modified leaf at the top of a pseudobulb);
3) stem form and shape (were these creeping or slender and leafy, or did they have swollen or fusiform pseudobulbs);
4) lip shape (lobed or entire); and
5) inflorescence position (basal, lateral or terminal).

A group which he called Euepidendrum contained plants with leafy reed-stems. This group now represents the some 300 members of the genus Epidendrum but since more recent molecular study, some groups of species have been removed from Epidendrum to form separate genera including Oerstedella. For example, Oerstedella centradenia.

Likewise, we now consider members of genus Nanodes separate from Epidendrum. (the picture is Nanodes medusae)

In the 1960's, Dressler looked at separating a group of pseudobulbous Epidendrum (subgenus Encyclium Lindley) into the genus Encyclia. These species produce flowers without a spathe and have lips more or less free from the column. Doesn't it seem that not long ago we thought the name game over at least as far as these two are concerned. Encyclia separated from Epidendrum. Easy! Pseudobulbous ones are Encyclia and reed stems are Epis. Right? Wrong! When we looked more closely, some species didn't quite fit either genus which has led to taxonomic discussion as we see in books like that of Withner & Harding, 2004. We should remember that it has taken 40 years for some so-called ˜new" names such as Encyclia cordigera to take hold and we still find the odd plant incorrectly labeled Epidendrum atropurpurea. It does take a while for changes to become accepted or in common use. Be prepared for more changes. The best advice is to keep plants labeled with your preferred name and the synonym. This way, you will be prepared to accommodate show schedules and to use the currently accepted name if ever you plan to register a hybrid made with the species/hybrid in hand. Keep informed with changes accepted by the International Orchid Registrar. Note, for example, that Encyclia (E.) Ã- Cattleya (C.) is now called Catyclia (Cty.).

With the advent of molecular technology, where one can probe the secrets of the genome to discover relationships that had been guessed at by a few but until now remained unproven, additional studies are shedding light on the complex world of orchid relationships. What is presented here is not necessarily the end of the story for there will undoubtedly be taxonomic arguments on some finer points, and perhaps a few new species to throw a wrench in the works. Van den Berg et al. (2000) emphasized that "much more thorough taxonomic sampling" is still required for groups such as Encyclia (in the broad sense) and the Epidendrum alliance.

Epidendrums that are still Epidendrums

South American Epidendrum calanthum, for example, has leafy reed-like stems much like other true Epidendrums. The flowers have lips attached to the column along the entire length (adnate). Plants have a rhizome from which new shoots arise. This may be creeping or ascending as we see in a plant of the Brazilian species, Epidendrum janeirense. The arrow points to the emerging new growth. Such plants are best grown mounted.

Epidendrums that are now considered as Encyclia according to Whitner & Harding and others.

Note that Encyclia species have columns free of the lip while flowers keying out to Anacheilium and Prosthechea have the column fused somewhere along the column length.
Encyclia alata - Mexico through Central America

Encyclia bractescens - Central America

Encyclia cordigera, possibly var. leucantha from Central America, Columbia, Venzuela

Encyclia nematocaulon - Cuba, Mexico, Central America

Encyclia tampensis - Native North American species from Florida and possibly also the Bahamas and Cuba. The Encyclias that I have just illustrated have many common features that would be easy to recognize. Review the lip structure.

Epidendrums now called Euchile.

We know some of the showy species belonging to this genus. Mexican endemic, Encyclia citrina, grows upside-down! The lip is large and not adherent to the column but also, the upper and two lateral column teeth can be seen extending past the column tip. Euchile citrina and Euchile mariae also segregate as a separate group in molecular analyses such as that published by van den Berg et al. Here we see Euchile mariae still considered by some as Encyclia mariae.

Species considered as Prosthechea by Higgins but argued to be Anacheilium by Whitner & Harding.

Whither & Harding's key separates based upon the degree of column separation from the lip and column tooth structure, then separates species with non-resupinate flowers again on column tooth structure and lip length amongst other characteristics. Here we see the characteristics in the West Indian/Central American orchid, Prosthechea/Anacheilium fragrans The cupped cockleshell lip is uppermost in these non-resupinate flowers. Some have reduced lips as in the Brazilian species, Prosthechea/Anacheilium vespa. There are always some species which do not quite fit the criteria. One "odd man out", Prosthechea vitellina, has resupinate flowers. This stunning species comes from Mexico through Central America.

I add one other species, once considered by Lindley as belonging to a Epidendrum subgeneus called Hormidium. Lips are fused to the column; stems are more or less swollen pseudobulbs. The flowers of the Florida/tropical American Prosthechea/Hormidium (according to Withner & Harding) pygmaeum are tiny. Withner & Harding have separated Hormidium from Prosthechea based on several characteristics including the shape of the column midtooth being pointed, not rounded as in Prosthechea.

N_Calif_Kathy
So its mostly the molecular differences that precipitated the separation? I guess my question is which came first, historically speaking? Did Taxonomists think these should be separated, but lacked a convincing tool like molecular analysis to further their proposal to separate out into groups?

MarilyninOttawa
Molecular differences have solidified decisions. Historically, the first divisions were based on easily seen characteristics. Now, we also look at cellular structure and even geographical distribution.

John_in_Arcadia
But aren't the colums of these last 3 all somewhat "winged" to various extents? vespa and fragrans

N_Calif_Kathy
I thought the same thing. It might be one thing for a taxonomist to say 'look the column is winged and the lip isn't adnant' and another to say 'look the column is winged and the lip isn't adnant and also look and the genetic difference in their markers....'

MarilyninOttawa
Plants and flowers can look more or less similar but can evolve separately to reach the same form. Character keys are just that. Keys to assist in preliminary identification based upon characters used by the constructor of the key. I feel that molecular evidence is somewhat stronger but there are still going to be grey areas.

N_Calif_Kathy
I know when I was in school the criticism was that judging physical characteristics were somewhat arbitrary, and profs hoped for a way to look at their genetics as a way to sort species. Of course who knew that would become arbitrary too, LOL!! I guess the philosophers were right...there is no truth...

MarilyninOttawa
I suggest that growers examine their flowers closely to see what features of the column, lip, and column teeth can be noted. Encyclia species have columns free of the lip while flowers keying out to Anacheilium and Prosthechea have the column fused somewhere along the column length. Anacheilium has column teeth equal in length. Prosthechea has column teeth unequal in length. I regret that I do not have dissected flowers to show what Whither & Harding have argued.

N_Calif_Kathy
Wow... that sort of takes the fun out of it... I follow what you are saying, though. I'll just have to bow to their superior knowledge, LOL!! (OK I'll shut up now)

MarilyninOttawa
One aspect we have not discussed (and I have not prepared for) is the chromosome number and breeding patterns formed by these genera. Some interbreed freely while others, often the small separated genera, only breed with species closely allied according to molecular data.

N_Calif_Kathy
Would this tie in at all with reedstem epis habit of parthenogenesis when used as the pod parent? Most hybridizers use reedstems as the pollen parent.

MarilyninOttawa
There are reed-stems and there are reed-stems! I have used Epi. calanthum, janeirense and pseudepidendrum as seed and pollen parents with quite a range of progeny in either direction. The most popular reed-stem epis such as Epi. cinnabarinum, radicans, secundum and ibaguense have been heavily hybridized in tropical garden settings. Some polyploids have undoubtedly been selected along the way. I have not personally used any of these for breeding purposes but suggest that only true species be used to avoid problems. It is quite possible that some such as Epi. radicans are either autogamous or apomictic.

Susan-from-Idaho
Are Encyclias the only "Epis" that will hybridize with Cattleyas?

MarilyninOttawa
Good question Susan. I have hybridized Epidendrum pseudepidendrum with a hybrid Cattleya making Epicattleya Melon Surprise. However, Epidendrum capricornu which is related to Oerstedella centradenia at a molecular level, will not work.

N_Calif_Kathy
I know Fordyce has done a few crosses with reedstems onto catts. I just did a quick Wildcatt search and only come up with Epc Meadow Frost by Fordyce, a Epi. mariae cross. (Epi. mariae x Angelwalker) But he had a reed stem one going a few years ago too... He also has a Kir. Sunseeker which is Hazel Boyd x mariae

CynthiaPrescottAZ
EC Nebo has been around oodles of years. C Claisiana X E. obrienianum

Susan-from-Idaho
Oh yeah (I slap myself upside the head). I used to have an E. marie x C. granulosa cross. It smelled real nice. Seems like I recall an E. stanfordianum x Catt cross. Can't recall seeing intergeneric Epis radicans, secundum or ibaguense, etc. crosses

MarilyninOttawa
Epicattleya Fireball is cross with Epi. cinnabarinum. In fact, we can go one step further as I have with Epc. Melon Surprise. I crossed this with Epi. ilense to make Epc. Fringe Festival.

N_Calif_Kathy
Now that you mention it there are a few ilense hybrids that are popular too!

MarilyninOttawa
All those reed stems mentioned have been registered as parents of Epicattleya. There has even been a hybrid between the southern US native, Epi. magnoiliae (aka conopseum).

I hope this presentation answered as many questions as it raised comments. As I said earlier, keep abreast of developments at the Orchid Registrar link - I know that we (our society) will be examining the new generic names to create guidelines for exhibitors in the coming show season. We will only use those changes accepted by the orchid registrar.

Jade_in_GR
I have a question regarding the renaming. I now see a genus name Anacheihium being used instead of Prostechea. Which is now being accepted? This was especially attached to the cockleshells. Eg. Anacheilium abbreviata previously Ept repens, Ahacheilium Radiatum.

MarilyninOttawa
You can use Prosthechea in most cases I would expect. Encyclia species have columns free of the lip while flowers keying out to Anacheilium and Prosthechea have the column fused somewhere along the column length. Anacheilium has column teeth equal in length. Prosthechea has column teeth unequal in length. Species considered as Prosthechea by Higgins but argued to be Anacheilium by Whitner & Harding. Whither & Harding's key separates based upon the degree of column separation from the lip and column tooth structure, then separates species with non-resupinate flowers again on column tooth structure and lip length amongst other characteristics. Here we see the characteristics in the West Indian/Central American orchid, Prosthechea/Anacheilium fragrans.

Jade_in_GR
Thanks. Marilyn, guess I will have to change my files back to Prostechea. We have our big show later this month and I am writing the show schedule. Also, when I share plants with newbies, I like to make sure the names are up to date.

CynthiaPrescottAZ
For those of us that are longtime collectors of reed stemmed epis, are there sources of info that will help us identify our commom reedstems which might be species?

MarilyninOttawa
Regarding the identification of reed stem species. First of all, check to see if the flowers are resupinate or non-resupinate, that is, if the lips face up or down. Do not be pre-occupied with color as this characteristic can be highly variable. I have not done this with reed stems but if you have a microscope/or access to one, you might like to check guard cell dimensions in the leaf lower epidermis. Polyploids usually have 25% larger guard cells than diploids. Being polyploid would not mean that they were hybrids but could be suggestive. I can research identifiers for a later presentation.

N_Calif_Kathy
Here's an article from the Archives too, Cynthia.

-end

Prechat Handout

Orchids whose name begins with 'E'
OR
Once upon a time there was genus named Epidendrum
Marilyn H. S. Light
Copyright 2005

The genus Epidendrum was, like many of those root genera, a once all-encompassing collection of somewhat similar orchids found growing on trees in the neotropics. The name was published by Linnaeus in 1759. Now some of these orchids have resupinate flowers and some do not. Some have swollen pseudobulbs with a couple of leaves on top and some have long reed-like pseudobulbs that are leafy along most of their length. Some have round capsules and others capsules that are triangular in cross-section. Still, for a long time, they were mostly lumped together into a group called the epidendrums. Lindley devised a way to separate sub-groups and then published a key to recognize 12 sub-groups (subgenera) in 1853. He subdivided the epidendrums according to a few basic characteristics including: 1) whether or not the lip was attached to the column; 2) whether or not the flowers arise from a spathe (modified leaf at the top of a pseudobulb); 3) stem form and shape (were these creeping or slender and leafy, or did they have swollen or fusiform pseudobulbs); 4) lip shape (lobed or entire); and 5) inflorescence position (basal, lateral or terminal). A group which he called Euepidendrum contained plants with leafy reed-stems. This group now represents the some 300 members of the genus Epidendrum but since more recent molecular study, some groups of species have been removed from Epidendrum to form separate genera including Oerstedella. Meanwhile, some of the Epidendrum L. (which contained what we now recognize as Encyclia, Prosthechea, Oerstedella, etc) were hybridized and the resulting progeny registered as Epidendrum. Intergeneric hybrids between Epidendrum L. and genera including Cattleya, some dating back to the 1850's, were also registered.

In the 1960's, Dressler looked at separating a group of pseudobulbous Epidendrum (subgenus Encyclium Lindley) into the genus Encyclia. These species produce flowers without a spathe and have lips more or less free from the column. Doesn't it seem that not long ago we thought the name game over at least as far as these two are concerned. Encyclia separated from Epidendrum. Easy! Pseudobulbous ones are Encyclia and reed stems are Epis. Right? Wrong! When we looked more closely, some species didn't quite fit either genus which has led to taxonomic discussion as we see in books like that of Withner & Harding, 2004.

We should remember that it has taken 40 years for some so-called 'new' names such as Encyclia cordigera to take hold and we still find the odd plant incorrectly labelled Epidendrum atropurpurea. It does take a while for changes to become accepted or in common use. Be prepared for more changes. The best advice is to keep plants labelled with your preferred name and the synonym. This way, you will be prepared to accommodate show schedules and to use the currently accepted name if ever you plan to register a hybrid made with the species/hybrid in hand. Keep informed with changes accepted by the International Orchid Registrar. A couple of useful links are provided in the references.

With the advent of molecular technology, where one can probe the secrets of the genome to discover relationships that had been guessed at by a few but until now remained unproven, additional studies are shedding light on the complex world of orchid relationships. What is presented here is not necessarily the end of the story for there will undoubtedly be taxonomic arguments on some finer points, and perhaps a few new species to throw a wrench in the works. Berg et al. (2000) emphasized that "much more thorough taxonomic sampling" is still required for groups such as Encyclia (in the broad sense) and the Epidendrum alliance.

References

Berg, C. van den, W. E. Higgins, R. L. Dressler, W. M. Whitten, M. A. Soto Arenas, A. Culham & M. W. Chase. 2000. A phylogenetic analysis of Laeliinae (Orchidaceae) based on sequence data from internal transcribed spacers (ITS) of nuclear ribosomal DNA. Lindleyana 15: 96-114.

Withner, C. L. & P. A. Harding. 2004. The Cattleyas and their relatives: The debatable Epidendrums. Timber Press Inc., Portland Oregon.

Orchid Registrar link - http://www.rhs.org.uk/publications/pubs_journals_orchid_hybrid.asp

Information about some accepted grex names, e.g., Catyclia (Cattleya × Encyclia)
http://www.rhs.org.uk/publications/orchidreview/download/orrevmay04.pdf