Biological Sciences Department
Index Herbariourm

Physalis: Calyxes

The shape of the fruiting calyx is a major character for sorting out Physalis species. Most U.S. species have a rounded or 10-angled calyx. However, several of our annuals fall into the 5-angled or pentagonal group. The tricky point to sorting this out is that the mature fruiting calyx of the "rounded" type often looks rather pentagonal in cross-section.

The terminology is a little misleading, but once you know what to look for, the types are pretty easy to distinguish. Basically, plants with rounded or 10-angled type calyxes have 10 major veins in the calyx that are all about the same size. Plants with calyxes of the 5-angled type have alternating large and small main veins, so that five are very prominent (making the angles of the calyx) and five are relatively reduced. When flat and dry (such as on a herbarium specimen) 10-angled calyxes tend to have a heavier texture than 5-angled calyxes, which often have a very fine, tissue papery-like texture.

5-angled Physalis

The two central calyxes pictured are of the 5-angled type. Run your pointer over the image to see the veins labeled. Note that every other major vein is quite prominent.

In Kentucky, P. pubescens and P. grisea fall into this group. South of us, the annual species P. cordata also belongs to this group.

10-angled Physalis

All the perennial Physalis species in Kentucky fall into the 10-angled calyx group, as well as the annuals not listed above.

The calyx pictured here could be described as looking pentagonal. Hover, the feature to note is that all 10 major veins are about equally as prominent. Run your pointer over the image to see the veins labeled.

This page has had [ [TextCounter Fatal Error: Could Not Write to File __herbarium_Taxonomy_Solanaceae_Physalis_PhysalisCalyx_shtml] ] hits since August, 2007.

Return to top.