Water Hog-louse

Our small garden pond (the same one that's home to the newts mentioned in a previous post) is also home to a thriving water hog-louse (aka water slater) Asellus aquaticus population - and this is their breeding season. This is a mating pair and eventually the female will carry her fertilised eggs around with her under the front of her flattened body. These are crustaceans which exhibit a considerable level of maternal care of their offspring and when the eggs have hatched the female will continue to carry her young under her body, between the front two pairs of legs until they're old enough to fend for themselves. Water hog-lice aren't too fussy about water quality and so will thrive in small aquaria, where it's easy to watch their reproductive cycle. 

The brown pigmentation of their exoskeleton takes time to develop and in the youngsters it's transparent, which makes it easy to watch the workings of their internal organs under a microscope. This one is a juvenile that is only just beginning to develop the vestiges of pigmentation .....

..... and this one is a little further along the road to adulthood.


Asellus is an isopod crustacean, meaning that all of its legs are of similar length, unlike the amphipods that have a combination of long and short legs.