Tropicals & Tender Perennials: Mystery Costus ID????, 0 by gingersrus

gingersrus wrote:
Okay, that narrows it down considerably. From Ecuador, basal bloomer, red curled-in bracts, spreading flower form vs. tubular, very hairy sheaths and leaves - most likely it is Costus longebracteolatus. I have not seen it in flower myself, but have seen a few photos and I have some info at http://www.gingersrus.com/botanical/description.php?PID=4006 . You will see that it looks quite different but that is just because the inflo is younger and the bracts and flowers are not as red. All the photos I have seen have mostly green bracts but I have heard that the form Mark Collins calls "Kiss of Death" has different looking inflorescence from the "standard" C. longebracteolatus.

I also have the section on Costus from Flora of Ecuador (just got it from Sweden last week) which gives a little more detail than what I have on that web page. Maas describes the bracts as "green or reddish tinged in the exposed part, covered part red, coriaceous, broadly ovate-triangular, apex slightly curved backwards".

It should be very easy to verify if you will dissect under one of the bracts and measure the bracteole and calyx. The bracteole should be very long (thus the epithet "longebracteolatus") from 32-42 mm long, and the calyx likewise fairly long for Costus - 17-22 mm long. I have some examples of Costus bracteoles at http://www.gingersrus.com/botanical/bracteole.htm and Costus calyx at http://www.gingersrus.com/botanical/calyx.htm
The ligules should be 10-30 mm long - http://www.gingersrus.com/botanical/ligule.htm

If your plant does not have the really long bracteole, there are a couple of other possibilities for Ecuadorian Costus - C. zamoranus or a basal blooming form of Costus amazonicus. But we can cross that bridge if necessary. This is sooooo much fun. Actually Ecuador is my next area to explore for Costus. I have started planning a trip for later this year, which is why I ordered the Flora of Ecuador volume.

Dave Skinner
http://www.gingersrus.com



Hairy stems on Costus longebracteolatus