On a special day towards the end of our May 2014 field trip, Essie, Leevi, Iain and I collected what appeared to be a Petalidium completely intermediate between P. setosum and P. halimoides. I’ve never seen anything like it.
A few intriguing observations: (1) it was growing vigorously and happily in a couple of minor, sandy drainages, but seen nowhere else along the way; I would have readily called it P. setosum, but (2) its leaves were glabrous instead of scabrous; (3) its inflorescences were nothing like typical P. setosum (lax, with wide bracts and bracteoles), but rather resembled perfectly those of P. halimoides (extremely congested with linear bracts and bracteoles); and (4) these plants were growing quite out of range for P. setosum. Like P. setosum, the plants did produce a musky honeysuckle floral smell typical of the former species.
Needless to say, I am very much looking forward to researching this, as soon as I have internet connection (the first time I’ve wanted it since our field trip began, to be sure!). It is mostly likely a naturally occurring hybrid, and one that needs a name….
Wild collected, Namibia, Klaassen et al. (awaiting data from Essie [WIND, COLO]); Photos by E. Tripp