[violapinnata]

Good morning everyone, I photographed last week (in pots but outdoors) what I believe to be a Tradescantia (or a Callisia). But I can not identify it further. Can anyone help me?

[Trevor Australis]

I suggest it is a colour form of Tradescantia virginiana. We have white and deep blue, and one with yellow leaves and deep blue flowers - all quite good in our Med garden in the Adelaide Hills. I don't water them through summer so they suffer somewhat but always increase and return year after year.

[oron peri]

Your plant is Elasis hirsuta (syn Tradescantia hirsuta) originated to Mexico,
a recent cultivar is known under the name Tradescantia 'Swallowtail'.

[violapinnata]

Many thanks Oron, In fact, I had come to a similar conclusion. My doubt is among Tradescantia hirta D.R.Hunt ( synon.: Setcreasea hirsuta Markgr.)  and Elasis hirsuta (Kunth) D.R.Hunt (synon.: Tradescantia hirsuta Kunth )
see for example:
http://www.plantillustrations.org/illustration.php?id_illustration=39835
http://www.tropicos.org/Name/50299071

[oron peri]

I had the same doubt as there is much confusion between the two species.
 We need to read the original descriptions of the two in order to decide which is which.