Solitary movement in joints with herbaceous plants remain the most interesting concept to me within’ Lamiaceae. Normally when you adjust a herbaceous plant in one direction turgor pressure is maintained and the tissue plasticly responds by moving back to an original orientation. Not in this case, the flowers will remain in a cocked right, or left position for days at a time before moving back in some cases. In other families, fabaceae for notable example, turgor response is opperated in a celular valve mechanism, Fabaceae has the morphological character located in it’s herbaceous joints called a pulvinus. The pulvinus allows members of Fabaceae to function in many different ways: can respond in extreme heat by folding or dipping certain sections of the leaves (Prosopis velutina) , in some cases can cause chain reactions to scare herbivores(Mimosa pudica), or at night when turgor function through photosynthetic pathways is minimized (Trifolium repens); but, they all have evolved this to solve for some kind of ecological pressure effecting relative fitness. This species in the Lamiaceae does not seem to have a reason for such dynamic response which is why it has always fascinated me on an evolutionary standpoint.
