Approximately male Catasetum Orchidglade intersex flowers

My plant of Catasetum Orchidglade has bloomed many times over the years.  The inflorescence normally bears only male flowers, or infrequently, female flowers.  On very rare occasions the plant has produced intersex flowers.  I don’t know what causes this.  The phenomenon of intersex flowers has fascinated and vexed orchid growers and taxonomists for centuries.  This account is about one time in which my plant produced an inflorescence with a few intersex flowers that were an approximation of the male form.

In this particular inflorescence the first flower opened as an intersex that was almost completely female except for the sepals, petals and a bit of the lip.  But the rest of the flowers in the inflorescence were male flowers with shapes that approximated the shape of a female flower without getting it quite right.  Unfortunately all the male flowers were stripped of their pollen by insects before they opened fully.

But you can see that flowers that were supposed to be quite flat and wide were instead massive and chubby.  Not two flowers of the inflorescence were exactly alike.  The last flowers in the inflorescence had typical male colors and pollen ejection mechanism but their shapes differed wildly from both the typical male and female flower form.

The program that makes the flowers male or female went awry and produced flowers that tried to approximate the female form while preserving the unique characteristics of the male flower.  The result was flowers that were like an intermediate flower designed by a committee.  Even if the flowers had opened fully, the distorted shape means that the insect would not have been in the right position to receive the pollen when the pollen throwing mechanist was triggered.  

Catasetum Orchidglade, curious hermaphroditic intersex flowers

Male flower

Intersex flower

Intersex flower

intersex flower

I have had this plant of Catasetum Orchidglade for about twenty years now.  It has bloomed many times during those years.  One thing that is interesting of Catasetum is that they normally produce imperfect flowers, those are flowers that instead of carrying both male and female parts are either male or female.    The male flowers are brightly colored, have a mechanism for shooting pollinia and are relatively numerous.  The female flowers are green, sack like, and only a few are produced in an inflorescence.  It seems that plants need to get full sun to be able to produce female flowers.¹

Rarely, Catasetum produces hermaphroditic intersex flowers.  In the case of my plant, all three flowers were slightly different in the expression of the male and female parts.  The male flowers, in the case of Catasetum Orchidglade, are bright red with some yellow/white spotting.  The female flowers are apple green.  Given this, you can easily see in the photos which parts of the flower express the male appearance and which are female.   I don’t have a clue as to what prompted this event.  With a single exception in which the plant produced female flowers, when I had this plant in full sun, all other bloomings to this date had been male flowers.

The wide variability in color, number and shape on the flowers of Catasetum was a real headache of orchid taxonomists when this genus was first found.    Much confusion occurred in England in the heyday of the orchid fever in the nineteen century when plants sent from Center and South America would bloom with flowers that were radically different from what the plant exporters had described to the buyers.  For amateur orchid growers this means that the culture they give the plant can make it produce flowers that don’t look like what they expected.   

¹Northen, Rebecca T.  1990.  Home Orchid Growing. Fourth revised edition