Oxalis is a huge genus in the Oxalidaceae family found in many parts of the world, but with a large number found in South Africa and South America. Oxalis was the subject of the PBS list topic of the week in November 2003. To read the introduction by Robin Attrill for this topic view this link. Another post with a lot of good background information on this subject was in this list post from David Victor. For the most recent comprehensive information about the names of the species see Clifton, 2004 in References
The first two photos below taken by Bill Dijk are a collection of Oxalis species painted by botanical artist Zoë Carter from Nelson, New Zealand. Bill has kindly added the names in the second photo. The next three pictures show flowers and leaves scanned by Ron Vanderhoff. He also has added the names of the leaves, but the limits of the wiki has meant the file had to be reduced. These photos show the great number of flowers that can be in bloom at the same time in his collection and the great diversity of leaf types of this genus.
See these wiki pages Miscellaneous oxalis - South African oxalis A-B – South African oxalis C – South African oxalis D-E – South African oxalis F-G – South African oxalis H-K – South African oxalis L-M – South African oxalis N-O – South African oxalis P - South African oxalis R-S - South African oxalis T-Z - South American oxalis or click on the name in the table below to learn about some of the species.
Miscellaneous oxalis - South African oxalis A-B – South African oxalis C – South African oxalis D-E – South African oxalis F-G – South African oxalis H-K – South African oxalis L-M – South African oxalis N-O – South African oxalis P - South African oxalis R-S - South African oxalis T-Z - South American oxalis
More information about Oxalis is found on the websites listed below:
Andrew Broome's oxalis site from New Zealand -- Bill Baird's site from the USA