Rhynchosida physocalyx

Buffpetal - Rhynchosida physocalyx
East fork of Ready Pay Gulch, North of NM-152
East of Hillsboro, NM 

Rhynchosida physocalyx, Buffpetal, is typically found at middle elevations in the Black Range, generally in disturbed soils.  We found it at an elevation of about 5,400’ in the east wash of Ready Pay Gulch, north of NM-152, east of Hillsboro, New Mexico, USA.  It is also known as Bladderpod Sida and has a synonym of Sida physocalyx, which may explain why I spent so much time trying to fit it into the Sida genus, the other explanation; sheer ignorance, I have discarded out of pure arrogance.

I do not have a photograph of the fruit of this plant but it is apparently quite striking.  

This species was first described by Asa Gray and redescribed by Paul Arnold Fryxell in 1978.  Fryxell was an expert on Malvaceae (Mallow).  

Within the United States, the range of this species is limited to Arizona, Oklahoma, Texas, and New Mexico.  It is found southward into South America.

The illustration below is from:  Martius, C., Eichler, A.G., Urban, I., Flora Brasiliensis, vol. 12(3): fasicle 109, t. 56 (1891) shows the fruit mentioned above.


© Robert Barnes 2018-2023