Ghosts in the shell

You probably don't know, but I have a pet giant African land snail (Achatina fulica) called 'Chickpea' because that's what s/he (the species is hermaphrodite) looked like when young. S/he's now a bit larger and 'Brazilnut' might be more accurate.

Chickpea the not-yet-giant African land snail.

However, the keeping of exotic invertebrates is not today's topic. While cleaning Chickpea's tank, I noticed some tiny white dots moving rapidly around the snail's foot and disappearing behind it. Of course, I grabbed a camera and then went online. It didn't take long to find out that this was an infestation of Riccardoella mites, probably R. limacum.

Riccardoella mites.

More Riccardoella mites.

I use the word 'infestation' because these are parasitic. They were previously though to be commensal, feeding harmlessly on mucus, but are now known to be blood-feeders. This may not be too much of a problem unless they are numerous, but their feeding can lead to secondary infection via the tiny wounds. They are also difficult to remove as they are very swift and hide in the pneumostome (breathing pore). Rinsing the snail with water is likely to help limit them, and if lucky may remove them all eventually, but the only other known option is to buy the predatory mite species Hypoaspis miles which will target them, although these mites are only available in large quantities for use across whole gardens, allotments and so on up to larger scales. It is likely that the mites came in with the soil used in Chickpea's tank and they are common in the wild, being found on various native slugs and snails. So, I will see if washing works, and if not, maybe a 'mite-share' scheme will do the job. Until then, I don't have access to electron microscopy, but if you'd like more info and some excellent images, I recommend this page.