Notodoris from Sunshine Coast

Wayne,
Notodoris gardineri feeds on a calcareous sponge called Pericharax. It can often be found nestled in a large pit or cavity in the dull brownish yellow sponge which it has produced while eating away at the sponge tissue. Sometimes a pile of white calcareous spicules will be piled up alongside, but I do not know if they are spat out while the sponge is being eaten or defecated after digestion. There is another very similarly looking species, Notodoris minor which is also yellow but has a pattern of black lines rather then patches. Whether these two are distinct species or just part of a range of colour variation is unknown. A third species, Notodoris citrina is plain yellow. It is slightly different in shape and feeds on a different species of sponge. At present, species of Notodoris, which can grow to 12cm or more in length, are considered to be closely related to the genus Aegires, with species usually less than 5mm long. They have similarities, but it is possible that these similarities are related to their similar life styles rather than there phylogenetic history. Species of Aegires also feed on calcareous sponges... Bill Rudman.