To extinction and back again, a rare orchid from Kyushu, Japan

Kyushu, Japan’s southernmost main island is home to an extremely rare orchid species, Odontochilus hatusimanus.  This plant is so rare in fact that it was listed as extinct for several decades before being rediscovered in the late 1990s.  It just so happens that I live right next to a mountain that has one of the remaining populations left in nature.

O. hatusimanus is a low growing evergreen terrestrial orchid.  The ovate leaves originate out of a central growing point and form a small, neat rosette.  They are glossy, dark green, lightly veined, and about 5-6 cm long and 3-4 cm wide.  The rosettes grow from a trailing rhizome that is at or near the surface of the ground.  From the center of the growing point a single hairy branch less flower spike grows to a height of 6-10 cm and sports up to 8 small flowers about 1 cm across each.  The pure white lip is cleft in the center forming two lobes that are slightly serrated. The remaining sepals and petals are covered in long white hairs and are pinkish green in color.  These don’t fully open and thus form a hood-like structure.

Odontochilus hatusimanus plants
A large clump of Odontochilus hatusimanus in habitat, Fukuoka Prefecture, Kyushu.

It is a denizen of wet broad leaf evergreen woodlands of Kyushu Island, Japan, preferring the wettest sites possible, growing nearly in small streams and areas that commonly flood.  In these areas Calanthe reflexa, another terrestrial orchid, grows sympatrically.

This rare delight was first described by science in 1957 and was thought to be extinct, however, just a few decades later it was rediscovered. Currently it is only found at two sites on Kyushu, in Kagoshima and Fukuoka Prefectures.  The first rediscovery was in Kagoshima in 1999, and shortly thereafter in Fukuoka.  It remains critically endangered.

Through shear dumb luck and an observant eye, I stumbled upon a nonflowering plant back in May 2004  on one of the local mountains.  Unfamiliar with the local flora at the time, I wasn’t sure of its identity, but I guessed it to either be related to the genus Goodyera or to be a Goodyera itself.  A search on the internet and consultation with a native orchid expert IDed it as Goodyera foliosa.  I tried to find it in flower later that season, but the only plant I knew of grew no spike that year.

Odontochilus hatusimanus flowering plant
The plant flowers in late July in its native home.

In 2005 I returned in late August and found a small scattered colony already in seed.  That was a bit confusing since G. foliosa was supposed to bloom in August and September along with its cousins G. schlectendaliana and G. velutina, two species found in the general area.  The following year I was determined to photograph the flowers and made repeated trips to the colony starting in mid July.  I was finally rewarded in late July, finding two plants in perfect flower.  I sent the shots off to an orchid friend and he replied that it was not the Goodyera after all, but rather the extremely rare Odontochilus hatusimanus, a species I had never heard of.  What a thrill to have found such a rare species in my own backyard!

To my knowledge it has never been cultivated, though given the high profile of the colony near my house, it has no doubt been collected.  I have heard that unlike other Goodyera relatives, the seeds of O. hatusimanus are difficult to flask.  The issue seems to be their sensitivity to bleach, a agent used to sterilize the seed.  Perhaps green pods would work better since the embryos are never in contact with the bleach.

Odontochilus hatusimanus rosette
Odontochilus hatusimanus grows its glossy leaves in small rosettes along a creeping rhizome.

All knowledgeable people I’ve spoken to about this plant concur that it will be truly extinct within a few decades in the wild if nothing is done to help it.  In my short time of observing this species, I’ve seen several individuals “disappear”.  I suspect that they are being washed out by floods during the monsoon season.  Where they end up is a mystery.  Perhaps they find a new purchase further down slope and re-grow or perhaps they desiccate and die.

To see this species in the wild and in flower, check out this video:

Odontochilus hatusimanus flower
Odontochilus hatusimanus has small flowers, no more than 1 cm across.

Reports from some observers suggest that wild boars are also taking a toll on populations by digging them up and burying them, though I haven’t seen this.  The largest patch I’ve ever found, around 50 rosettes, grows alongside a path.  In 2008 I went up in mid July, just before the flowering season, to check on them.  Trail crews had weed-eated the entire patch down to nubs!  I used quite a few explicatives and anyone in range must have though I’d gone mad.  That group recovered to half as many plants in the following seasons, but this event underscores this species’ vulnerability.

Odontochilus hatusimanus seed pods
Seed pods are commonly set, so there is hope for this species’ reproduction.

Anyway you look at it, this plant’s future in the wild is very shaky, so cultivation seems its most likely chance at survival.  Plants set seed readily most years, so there is hope for the future, but for how much longer?  Not a beauty, maybe not even important in the long run, O. hatusimanus yet clings onto the steep slopes of Kyushu’s wet forests.

 

5 Replies to “To extinction and back again, a rare orchid from Kyushu, Japan”

  1. How nice it would be to have all of the “” Botany Boy “” information put in to book form. Staring at a computer screen is not ” my cuo of tea ” but the BB website is !!

    1. Thanks for the compliment Ray. Yes, I prefer looking at paper as well. I’ve tossed around the idea of doing a book with a friend on terrestrial orchids, but it too would start as an e-book. Publishing costs aside, I’m not sure there would be much demand for such an obscure publication. Thank you also for inspiring me to start writing again, I’ve been focusing on videos more lately.

      Tom

  2. Hello again Tom

    E book Yuk !! Hope you get to do a paper version. I am sure it would be a winner. I will put a deposit down for a copy now ( despite the fact that I am on the wrong side of 90 !! )

    Sincerely Raymond

  3. Hi Tom,
    If you need help with the seed to germinate, a friend of mine in the Netherlands and myself would be interested in seed, to try to germinate and create for you the whole procedure to send to you.
    My friend in the Netherlands is a professional grower and he is very succesfull with jewel orchids.
    If the idea interest you, take contact with me, through my email. ^_^

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