Edwardsiella andrillae, an Antarctic species of sea anemone that lives upside-down, burrowing into the sea ice and projecting its tentacles into the frigid water below.
The weird and wonderful pom-pom anemone rolls across the deep seafloor.
Pom-pom anemones, Liponema brevicorne, are amazing and adaptable invertebrates. This anemone resembles an unusual tentacle-covered dome unlike the more common stalked column body associated with many other anemones. Even within the unique body shape, there is variability. Sometimes it is observed in a low, deflated position, while other times it is puffy with tentacles extended.
While other species of anemones stay attached in one place, pom-pom anemones can be mobile. Using their muscles, they can contort their body into a barrel-like shape. They roll across the seafloor like a tumbleweed in the desert, propelled by ocean currents. It is speculated that this behavior allows them to scavenge and seek out more nutritious habitats in search of plankton and small crustaceans.
Liponema may be an important link for other animals, both in terms of habitat and as a food source. Shrimp, amphipods, and even fish have been observed using these anemones as shelter among the relatively flat, muddy seafloor. MBARI researchers have also found that pom-pom anemones may be an important source of food animals such as sea spiders, or pycnogonids. The sea spiders appear to suck material from the anemone’s tentacles. Luckily for pom-pom anemones, this does not appear to harm them. In fact, pom-pom anemones can shed tentacles, giving spiders an on the go treat.
The snail in this photo is identified as either Harpovoluta charcoti,Provocatorsp., or Provocator corderoi. The sea anemone (Isosicyonis alba) is probably always attached to a gastropod snail, and it occurs in the Antarctic, in the southern Atlantic, and South Chile.
