Can you ID this jellyfish?

In Mexico this summer we came across a nice jellyfish and scientist/videographer Bruce Carlson caught some footage.  I admit that Scyphozoans are a real weak point for me.  Can anyone identify this for us?

Elegant little thing, right? See more videos on my YouTube channel

Comments

[Al Dove]

I had one vote on Facebook (Paul Clarkson at Monterey Bay Aquarium) and one vote on Twitter (Kevin Zelnio from DeepSeaNews) for Aequoria sp. Google that and you'll see many similar, so I think they might be right. Thanks gents!