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Category Archives: Sacoila

Leafless Beaked Ladiestresses, Dressed Up But No Visitors

Sacoila lanceolata

(Translates roughly as sac-lip, referring to the chinlike sac near the flower base.  Lanceolate leaves resemble a spear tip.)

Orchidaceae, the Orchid Family

Florida is an isolated long thingamabob jutting rudely into the almost-tropics off of the mainland U.S.    Except for raised sand ridges, scrub, South Florida was underwater until not many thousand years ago, a wink in evolution time.  Where did Florida acquire its hot-climate species? From the American Tropics in large part.  Many Florida species extend southward to South America.

Given the need to cross water to get here, you might then expect many of our species to be dispersed easily…by sea currents, by storms, by birds, by pre-European ancient seafarers.    Fern spores and orchid seeds are dust in the wind, no doubt arriving by airmail daily.

Sacoila lanceolata 6

Sacoila.    All photos today by John Bradford.

Showing up precedes the greater challenge of taking hold and spreading, which brings us to today’s orchid.    Sacoila lanceolata ranges from its origins probably in South America to a marginal outpost in Florida.  It likely had no problem arriving in the sunshine state, but multiplying and spreading presented a special hurdle.  Let me explain.

Over the last couple weeks Sacoila has flaunted its red flowers on a near-leafless stalk  in a soggy shaded swamp.  It displays those big blossoms proudly, but to whom?  Any textbook will tell you red tubular flowers that size with no fragrance are all about hummingbird pollination.  And that is a problem, because hummingbirds are  too scanty for reliable floral sex services in South Florida.  Why then is this little showoff  putting on the ritz for nobody?

The first part of a reasonable answer is easy:   it evolved elsewhere with plenty of hummingbirds, and then seeds blew to Florida and grew where it does not know its display is useless.   A little depressing, and then we wonder how without being able to complete its sexual cycle the forlorn orchid managed to spread across much of Florida.

Botanist Paul Catling looked into this question back in the 80s.    The answer split surprisingly into two answers.    First answer:  in South Florida these orchids, instead of pollination, form clonal seeds where the embryos are tiny bits of the mother plant.  No hummer help required.

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The second answer is that one population of today’s species, called variety paludicola, has a different skill, pollinating itself.

How bout that!  A species stranded in Florida without its natural pollination agents “invents”  not one but two birdless ways to make seeds.   Evolution is inventive.

Which came first, the orchid coming to Florida and then evolving pollinator-free seeds?    Or, alternatively,  did members of the species somewhere else develop one or both of the sexless seed-making mechanisms, empowering them then to invade beyond the range of their original pollinators?  I vote for the second scenario.   In fact, the self-pollinating  variety is reported from the Caribbean.

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If Florida is home to far-ranging species  colonizing apart from their usual pollination agents,  there must be additional species here with tricks similar to those of our red-flowered friend.  Plenty  Examples of local plants able to sidestep normal pollination include other orchids, pitch apple (one big female clone in FL),  daisy fleabanes,  dandelions,  Fakahatchee grass,   and agaves probably brought to FL by ancient humans.

Don’t get hung up on the word “leafless” in the name.    Leaves form, sometimes coincident with the flowers and sometimes at a separate time, and their photosynthesis feeds a hunky root system.   By the time the fancy flowers brighten the world, there’s been a lot of  root-building off-stage.     The plants probably go years without flowering at all.

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Posted by on March 31, 2017 in Sacoila, Uncategorized

 
 
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