Heterostyly in the American bulb-bearing Oxalis. Floral morphs associated with tristylous and distylous breeding systems. Arrows indicate legitimate pollen transfer (Darwin, 1877). In fully functioning heterostylous breeding systems, pollinations other than those indicated by the arrows do not result in fertilization of ovules. Redrawn from Weller, et al. (2007).

Breeding system, Woody vs herbaceous, Storage morphology, Leaf type, and Geographic range, all coded along the phylogeny we infer for Oxalis.

Oxalis calva(?) on the edge of Santa Catarina, about 1200 m. This is a mid from a trimorphic population.

Oxalis macrocarpa, AG49. A long from a trimorphic population.

Well-pressed flowers of oxalis potamophila. A short.

O perdicaria 3686. A mid.

Oxalis floribunda 3612. One member of a tristylous populating on a grassy roadside east of Lages.

Oxalis serpens 3597, Parana Brazil. A short in a trimorphic population.

Oxalis pes-caprae. A cosmopolitan weed originating in southern Africa. This individual is a tristylous short.

Oxalis morelosii, a distylous long.

Oxalis nelsonii.  This individual (AG66) is a long, from a trimorphic population in Oaxaca.

A tristylous mid; from Calli, Marian, Anna, and Josh.

Calli, Marion, Anna, and Josh made this great image of a tristylous, short individual, preserved as a herbarium specimen.

Oxalis enneaphylla, Torres del Paine NP, Chile, Walking tour from Hosteria Mirador del Paine to Sierra Toro.  Tristylous longs.

http://www.flickr.com/photos/rienpieterman/

A long morph of the tristylous species, Oxalis brasiliensis. I snapped this in our greenhouse.  This is a SE South American species with small bulbs and heavy investment into vegetative reproduction.