![Antarctic jellyfish and sea angels [8238] | by josefrancisco.salgado](http://live.staticflickr.com/7031/6445522439_aeb301db42.jpg)
Antarctic jellyfish and sea angels [8238]
Observation Tube aka Ob Tube
Nikon D3s + 24-70mm f/2.8G | Ross Ice Shelf, McMurdo Sound, Antarctica, 13 Nov 2011
Main photo and inset: © 2011 José Francisco Salgado, PhD
Pteropods are specialized free-swimming pelagic sea snails and sea slugs. Sea angels are gelatinous, mostly transparent and very small, with the largest species reaching 5 cm. The angels have terminal mouths with the radula common to mollusks, and tentacles to grasp their prey, sometimes with suckers similar to cephalopods. Their "wings" allow sea angels to swim much faster than the larger (usually fused) wings of sea butterflies.
The polar species, Clione antarctica (see inset above), defends itself from predators by synthesizing a previously unknown molecule, named pteroenone. Because of this secretion, predators will not eat the sea angel and a species of amphipod has taken advantage of this fact: the amphipod will seize an individual of C. antarctica out of the water column, and carry it around for protection. Local population density of C. antarctica may reach extraordinary levels; up to 300 animals per cubic metre have been recorded. [Source: Wikipedia]
Antarctic jellyfish and sea angels [8238]
Observation Tube aka Ob Tube
Nikon D3s + 24-70mm f/2.8G | Ross Ice Shelf, McMurdo Sound, Antarctica, 13 Nov 2011
Main photo and inset: © 2011 José Francisco Salgado, PhD
Pteropods are specialized free-swimming pelagic sea snails and sea slugs. Sea angels are gelatinous, mostly transparent and very small, with the largest species reaching 5 cm. The angels have terminal mouths with the radula common to mollusks, and tentacles to grasp their prey, sometimes with suckers similar to cephalopods. Their "wings" allow sea angels to swim much faster than the larger (usually fused) wings of sea butterflies.
The polar species, Clione antarctica (see inset above), defends itself from predators by synthesizing a previously unknown molecule, named pteroenone. Because of this secretion, predators will not eat the sea angel and a species of amphipod has taken advantage of this fact: the amphipod will seize an individual of C. antarctica out of the water column, and carry it around for protection. Local population density of C. antarctica may reach extraordinary levels; up to 300 animals per cubic metre have been recorded. [Source: Wikipedia]