Is this a Nudibranch?

[sportyluis]

Hi All,

I just got back from Hawaii where my wife and I did a lot of snorkeling. On one of swims I found this small white slug and tried to photograph it with my old compact camera. I didn't get a good shot and couldn't get close enough without touching / impacting the coral so the best I could do are these cropped photos. It initially looked to me as a Nudibranch, however the size was bigger than the ones I've seen in the past.

Here are the relevant details:
Location: Maui, Hawaii
Size: ~2-3 inches?

If this is a Nudibranch, what kind is it?

 

[Storker]

2-3 inches (5-7.5 cm) is fairly big for a nudi, but far from unreasonably so. There are nudis a lot bigger than that.

Given how the critter looks in your pics, it's hard to imagine it being anything else.

 

[RogueClimber]

Believe that is an Imperial Nudibranch

They often are two together appearing longer than they individually are

 

[Searcaigh]

Certainly looks like a pair of what was known as Risbecia imperialis before they were renamed.

Known location is Hawaii.

 

[sportyluis]

Thanks for the responses! I like nudibranchs and had only ever seen really small ones before! I didn’t know they travelled in twos and perhaps that’s why it looked bigger.

 

[T.C.]

Yup.
That’s a nudibranch.

Hope that answers the question.