We got a new batch of tropicals in from Florida on 6 Nov., and found some of these on this one Sansevieria trifasciata. This is not the first time I've seen these; they're the same bugs (pretty sure) that were on my Trojan Sansevieria (story is at the whitefly profile, even though I've since concluded that they were not whiteflies).
The above is the best picture I'm capable of getting. Normally you can't see that much detail.
We've seen these on a variety of things, most of them relatively new arrivals:
Sansevieria trifasciata 'Laurentii,' 'Hahnii' (snake plant / mother-in-law's tongue)
Zamia sp. (cardboard palm)
Dracaena deremensis 'Janet Craig Compacta'
Dracaena deremensis 'Limelight'
unknown palm (I wasn't present when the infestation was diagnosed)
Cereus peruvianus (pic below)
It took a while to conclude that they were probably coming from Florida, because, you know, you hate to make these accusations unless you've been watching the plants in question really closely. They seem to be easy to get rid of on Dracaena and more or less impossible to eliminate from anything else, no matter what you spray or how often you wipe off the plant or what you use to do either of those things. The damage seems to be mostly aesthetic: when removed, the bugs leave yellowish spots where they were, which are permanent, but thus far none of the plants affected have looked like they were in imminent danger of dying.
I sent a picture to our supplier, who checked with the grower, who claimed that they'd never seen these before and they'd have to get back to us about what they were. Which I suppose might not be a lie, but I am deeply skeptical.
So. Anybody (especially anybody in Florida who might be a little less clueless than the growers) have any ideas? The last time I spoke to her, the supplier said the growers think it's not scale.