Deep Sea Pram Bug (Ikimon - Nature Techni Colour)

[bmathison1972]

Walk-around of the deep-sea pram bug, Phronima sedentaria (Forsskal, 1775), by Ikimon Co. (formerly, Kitan Club) - Nature Techni Colour, Deep Sea Creatures, new for 2017. Phronima sedentaria is an unusual pelagic amphipod that usually lives at a depth of 1000 m (0.6 miles). It is predaceous on salps (a kind of planktonic tunicate). Females tear into a salp, eat the gelatinous innards, and then use the empty shell as a barrel-like structure to swim around in while raising its young. This figure, which comes within it's salp shell, is not only the first amphipod figure (to my knowledge), but also the first salp (although not the first tunicate).

The figure was in a set of 8 'deep sea' critters, including mollusks, arthropods, and fish. The other 'new' species in the set was another arthropod, the giant ostracod Gigantocypris agassizii.

The figure is on a key chain, and I removed the chain and cut away the plastic ring to which it was attached. The salp is 40 mm tall. I cannot stretch out the amphipod itself, as it's a relatively firm, single-piece of plastic, but it's roughly 40-45 mm, making it 1:1 for a large female specimen! The amphipod easily comes out of its salp, it does not connect to the salp in any way but sits loosely within the barrel. The hole at the bottom is narrow enough that it will not fall out easily.

The detail on the amphipod itself it amazing. It was hard to photograph for the walkaround since it's transparent except for some structures in the head. I probably should have photographed it over a black or dark background.

The amphipod within the salp:



The amphipod itself:









I hope recent issues with Photobucket don't prevent others from posting their new critters...

[stemturtle]

Good to know that Phronima sedentaria is removable from the salp tunic.
It has been suggested that this amphipod was the inspiration for the creature in the sci-fi film Alien. See this link to decide for yourself.

[bmathison1972]

Good to know that Phronima sedentaria is removable from the salp tunic.
It has been suggested that this amphipod was the inspiration for the creature in the sci-fi film Alien. See this link to decide for yourself.

In biology we call that 'parallel evolution' 

[widukind]

Very nice too