Batwing slug

Sagaminopteron ornatum

Sagaminopteron ornatum is a species of gastropod related to the Bubble Shells.
Batwing Slug - Sagaminopteron ornatum This spectacular Sagaminopteron ornatum, is also known as the "Batwing Slug" because of its greatly enlarged wing-like parapodia. It was first found in Sagami Bay, Japan which gives rise to its name Sagaminopteron. One of the most fascinating features of the gastropterids is their swimming behaviour. The genus name Gastropteron can be loosely translated as "winged stomach", which is quite apt. Like most opisthobranchs, they are normally benthic crawlers, but when disturbed they can vigorously flap their greatly enlarged parapodia and remain suspended in the water column for some minutes.
They are very tiny in size, less than 5mm and although they are brightly coloured in purple and yellow, it is very difficult to find and see them. Anilao,Batangas,Batwing Slug,Batwing slug,Geotagged,Philippines,Sagaminopteron ornatum,Sea Slug,Spring

Naming

Sagaminopteron ornatum Tokioka & Baba, 1964
Purple Couple - Sagaminopteron ornatum The picture shows a pair of Batwing Slug - Sagaminopteron ornatum.  They are very small, the one on the left is around 5 mm and on the right is around 3 mm in size.  Was very happy to see a pair of them for the first time, usually seeing one is already lucky!

I'm not supposed to post pics with humans, but to give an idea how tiny they are, adding a link to my Facebook post to show how tiny they are :

https://www.facebook.com/photo.php?fbid=10155604602377491&set=a.383697222490.164145.793127490&type=3&theater; Anilao,Batangas,Batwing slug,Geotagged,Nudibranch,Philippines,Sagaminopteron ornatum,Summer

Distribution

Indopacific

Behavior

One of the most fascinating features of the gastropterids is their swimming behaviour. The genus name Gastropteron can be loosely translated as "winged stomach", which is quite apt. Like most opisthobranchs, they are normally benthic crawlers, but when disturbed they can vigorously flap their greatly enlarged parapodia and remain suspended in the water column for some minutes.

References:

Some text fragments are auto parsed from Wikipedia.

http://www.seaslugforum.net/find/sagornat
http://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:afd.taxon:34bd5bcb-e018-4fd7-b81e-9ef8bb3aa613#overview
Taxonomy
KingdomAnimalia
DivisionMollusca
ClassGastropoda
OrderCephalaspidea
FamilyGastropteridae
GenusSagaminopteron
SpeciesSagaminopteron ornatum
Photographed in
Philippines