Bullish on Stanhopeas

Stanhopea hernandezii

For a long time I thought of Stanhopea hernandezii as a sort of junior sized version of Stanhopea tigrina, that mastodon of the stanhopeas. Both give the impression of a massive cranium and formidable tusks. But it wasn't until this summer when we flowered both species simultaneously that I was able to compare them side by side.

Stanhopea tigrina

In profile, it's easy to see that the the bottom of the hypochile is rounded like a bowl in hernandezii, but flattened in tigrina.

Stanhopea tigrina, a second color form

Stanhopea hernandezii, dorsal view

The horns are round in cross section and slender in hernandezii, but flattened and broad near the base in tigrina.

Stanhopea tigrina, dorsal view

Stanhopea tigrina, dorsal view

Stanhopea hernandezii, lip and column

Notice the striking difference in the columns of the two species: hernandezii's narrow column compared with tigrina's broadly winged column.

Stanhopea tigrina, lip and column

Stanhopea tigrina, lip and column

Stanhopea hernandezii, lip

With the column removed you can see how much broader the epichile is in tigrina than in hernandezii.

Stanhopea tigrina, lip

Stanhopea tigrina, lip

Stanhopea hernandezii, lip in ventral view

Stanhopea tigrina, lip in ventral view

Stanhopea tigrina, lip in ventral view

Stanhopea hernandezii, column

Stanhopea tigrina, column

Stanhopea tigrina, column

Stanhopea hernandezii and tigrina are both endemic to Mexico. S. hernandezii occurs on the southwestern slopes of the Mexican plateau at about 1,600 to 2,000 meters elevation in the states of Morelos, Mexico and Michoacan. I can't find referennce to a specific pollinator for hernandezii. The largest fragrance components measured by Gerlach (in Lankesteriana 2010) are cinnamyl acetate (64%) and benzyl acetate (11%).

Stanhopea tigrina is known from  the eastern slopes of the plateau at about 1200 to 1800 meters in the states of Tamaulipas, Hidalgo, Puebla and Vera Cruz. Its pollinator is Euglossa viridissima. The chocolate fragrance described so often in the literature (but which I cannot discern in our plants) derives from the combination of phenylethyl-acetate, a primary component of the fragrance, and vanilline, one of the secondary components, according to Rudolf Jenny.

Our S. hernandezii, which we received from a commercial nursery as S. ecornuta, flowered in August and probably won't be on display again until next summer. On the other hand, we have quite a few S. tigrina in our collection. The flowers only last about three days, but it's definitely worth stopping by to try to catch them when they flower in August and September. They are magnificent.

Stanhopea tigrina

'Fierce' was the first word that came to mind when I saw this flower. Holding the heavy big boned flower in the palm of my hand gave me the unsettling sensation that I was holding the skull of an enormous hook-beaked raptor. No wonder people go gaga when they see Stanhopea tigrina.

Stanhopea tigrina is endemic to Mexico, where it grows on the eastern slopes of the Mexican plateau at elevations up to 1800 meters. We have a number of tigrina accessions of different provenance, all growing in our intermediate (60º night minimum) greenhouse, all doing reasonably well. However, this winter, on a trial basis, I'm moving some them to a greenhouse with cooler night temperatures for three months, to see if their growth improves.
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With the column removed, you can get a good look at the broad lip with its massive horns.

Even the column is impressive as you can see in this close up -conspicuously winged and splashed with red. Stanhopea tigrina isn't rare in cultivation, but most people would consider themselves lucky to have seen one. You can see our plants in the Orchid Display House. They flower off and on in late summer and early fall. The flowers last about three days.