Snail Flower, Snail or Corkscrew Vine confusion.
Kew and World Flora Online say Vigna caracalla is a synonym of Cochliasanthus caracalla.
Cochliasanthus caracalla, transferred from the Vigna genus is the only species in the Cochliasanthus genus.
It is commonly known in horticulture as Vigna caracalla or Vigna Caracalla.
It has long, dense clusters of scented white with purple streaked flowers that fade to yellow.
The keel is coiled into more than 1 circle.
Sigmoidotropis speciosa, like Cochliasanthus caracalla was originally in the Phaseolus then Vigna genera.
Common in Australia as an ornamental vine it is often sold as Vigna Caracalla.
Its shorter inflorescences only have a few purple to lavender flowers that have little or no scent.
The keel is not curled more than once.
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Sigmoidotropis.
Family Fabaceae > Subfamily Faboideae > Subtribe Phaseolinae.
There are around 8 or 9 species from Mexico to Tropical America.
They were originally in the Phaseolus then Vigna genera.
J.F.
