A last post before I go on holiday...

Yes, I go on holiday today for two weeks. We're going up the Cape West Coast, camping with friends, and will end up in the Richtersveld for the annual flower blooming. Apparently the flowers have already started showing themselves, so we should be in line for a good show.

Anyway, the reason for this posting is to show you a photo of a shell I picked up on a local beach last weekend. I'd never seen anything like it before but immediately thought it was in the Nautilus family...and I wasn't far wrong.

It is in perfect condition, with both sides equally shaped. At its longest point, it is only seven centimetres long, but I have seen articles that mention it can achieve lengths of up to twenty centimetres.



Meet the Paper Nautilus, which according to a website I found, is neither made of paper, nor is it a true nautilus. It is not even related to the nautilus, though both are cephalopods. It is, in fact, an Argonaut (argonauta argo) and supposedly "lives in pelagic habitats of the subtropics and tropics. Pelagic habitats are those of the free ocean water away from the bottom, especially at the water surface." What it was doing in Cape waters, I have no idea, especially seeing as the water was 12degC on the day I found it, which is definately not sub-tropical.

Here is the rest of the article...

The argonaut's shell is special among all molluscs. It is only built by the female, and only as case for the protection of the argonaut's eggs, that are placed inside in long threads. The female argonaut lives in the shell's entry and guards the eggs, until the young hatch. At the ends of the first tentacle pair the argonaut (argonauts like other octopus relatives have eight tentacles) has got wide sail-like flaps. Usually the female argonaut holds these flaps spread over the shell, but they also serve it to catch prey that swims into them.

The male argonaut is much smaller than the female. While the latter reaches a size of up to ten centimetres, the shell being up to 45 centimetres large, the male only reaches less than 2 centimetres size. The male argonaut is special because of its altered third tentacle, that is kept in a pouch until it is needed. Like among other cephalopods this tentacle is called the hectocotylus. The male argonaut, other than its larger relatives, often leaves its hectocotylus behind, the latter finding the target on its own. It seems obvious that the male argonaut dies after copulation, as no argonauts with their hectocotyli grown back have been found so far.

Generally living argonauts are difficult to find, possibly because of their pelagic way of life. Much more often their shells, sometimes, masses of them, are deposed on the shore by the sea. That way they also find their way into collectors' packs.

The scientific name of the paper nautilus, especially the largest species, Argonauta argo, is of mythical Greek origin. The argonauts were a group of Greek heroes that, led by Iason, travelled to Kolchis to gain the golden fleece. The were called that way, because their ship was the Argo. In Greek argonaut means "who travels on the Argo". The argonaut's discoverers probably mistook its sail-like flaps as a locomotive organ and thus drew the similarity to the mythical Argo.


Here is a photo from a Wikipedia article that shows the nautilus in its shell...amazing...




Anyway...see you all in a couple of weeks...take care...