A pinhead-sized transparent octopus drifting in open water before it settles to the bottom.
A tiny clear octopus with a rounded mantle, eight short arms held in a bunch, large dark eyes and a scatter of coloured chromatophores that flick on and off across the body. At this size the arms are far shorter in proportion than an adult’s, and the animal is often taken for a squid paralarva or a small jelly until it fans the arms. The species is not determinable from a photograph, so this entry is pitched at the order; blanket octopus paralarvae are the exception and have their own entry.
Most benthic octopuses spend their first weeks as paralarvae in open water, swimming by jetting, feeding on crustacean larvae and other small plankton, and dispersing well away from where they hatched. Mortality over this stage is enormous, which is why a female lays so many eggs. Those that survive settle to the bottom and become the animals a muck diver meets on the sand — the same species, at a stage almost nobody sees.
The chromatophores work from the start and the animal will flush dark under a light, which is one of the more interesting things to catch. It is also small, fast and frequently in mid-water with nothing to focus on, and a good proportion of attempts return an empty frame.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
