WHATSTHATFISH
Sea slugs & snails

Swallowtail Aglaja

Chelidonura hirundinina

Also known as: Blue Swallowtail Slug, Bubbletail Slug, Leech Aglaja, Leech Headshield Slug, Sperm Trading Sea Slug, Swallow Aglaja, Swallowtail Chelidonura, Swallowtail Headshield Slug, Tailed Slug

Adult
@reeph · nasugbu, Batangas, Philippines · March 20151 / 1
01

Overview

Found singly or in pairs, over rock and sand substrates and in tidepools of coral and rocky reefs rich in vegetation.

Often referred to as 'Nudibranchs' (but they are not) Cephalaspidea or Head Shield Snails are of the Opisthobranchia group, some of which still have a shell. The head shield from which this group attain their name, is a broadened part of the head, used to dig into the sand and protect the snail.

All opisthobranchs are hermaphrodites.

These beautiful slugs are usually brilliantly coloured as a deterrent against opportunistic predators. Some sea slugs secrete acid from stinging cells in their tentacles while others secrete acid from cells in their mantle.
They are slow moving, can swim or be propelled along either by muscular contraction or by millions of tiny hairs on the bottom of a fleshy 'foot', they have a voracious appetite and feed with a rasp like tongue.
They lay their eggs in a ribbon effect on the sand, in different colours depending on species.
Their main predator are other Sea slugs.

02

How to identify

Pattern
stripes
Behaviour
pairssolitary

Tap any trait to see other fish that share it.

03

Habitat & where to find it

  • Range · Indo-West Pacific, Caribbean
  • Country only · 1
LIVES IN

Found singly or in pairs, over rock and sand substrates and in tidepools of coral and rocky reefs rich in vegetation.

04

Adult photos 1

05

Discussion 2

Comments are checked by a moderator before they appear.

2 comments

  • LeeAnn Lyman· 14 Jul 2020

    Are leech headshield slugs hermaphroditic?

  • fishx6Top Contributor· 22 Jul 2020

    Apparently https://www.sciencedirect.com/science/article/pii/S0960982205010882

    Helpful
ALL STAGES
FOR THE MARINE-BIOLOGY CURIOUS

Deep dive

Taxonomy

  1. kingdomAnimalia
  2. phylumMollusca
  3. classGastropoda
  4. orderCephalaspidea
  5. familyAglajidae
  6. genusChelidonura
  7. speciesChelidonura hirundinina (Quoy & Gaimard, 1833)

SourcesWoRMSSea Slug Forum

06

More in the family

Head Shield Slugs (Aglajidae)