Eggs from the sand hopper

The sand hopper is a very common amphipod crustacean, found high up on sandy shores. The sand hopper broods its young, allowing easy collection of embryos by flushing eggs out from the brood pouch of females. The collected embryos were then staged. The examples below were collected in three different years of the field course and the different colours might indicate that they are actually two different species. Embryos of both colours were collected this year and examination of the males present suggested that there were two species of Orchestia, and no examples of Talitrus saltator, the sand hopper species original thought present at this site. Male anatomy, rather than female anatomy, is used to distinguish species of sand hopper.

A time-lapse recording of the comparatively slow cleavage of this species was obtained. The two cell divisions occurred over the 4.6 hours of this recording compressed 1500x into 11 secs.

A real-time video of a sand hopper embryo hatching.