Hermissenda crassicornis

There are 3 types of main appendages on this aeolid. Starting at the front or head, are two oral tentacles. These sense the path in front of them, to determine if it’s a safe and good direction to go. Chemoreceptors on these tentacles track their food. On top of the head are rhinophores (meaning nose bearing). Like antennae, they are keen receptors which ‘smell’ the water to help find food. The most striking part of this animal is the brilliant cerata plumage which practically covers its dorsal length. These cerata are gill-like projections which are used to absorb oxygen for its busy life of grazing on hydroids, anemone and tunicates. The cerata are also used for storing the stinging nematocysts of their prey.

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