Photo 53511821, (c) Andr Hospr, some rights reserved (CC BY)

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Attribution © Andr Hospr
Cc by small some rights reserved
Uploaded by ahospers ahospers
Source iNaturalist
Original https://www.inaturalist.org/photos/53511821
Associated observations

Photos / Sounds

Observer

ahospers

Date

October 7, 2019 02:42 PM AWST

Description

2.Center of the Photo, the Green mat colonial tunicate (MantelDieren)
ay be Trididemnum miniatum, which forms "white to emerald or lime green" cushions (size to 1 cm)
The Australian Ascidiacea, Part 4:
https://www.biodiversitylibrary.org/page/40460926#page/273/mode/1up

https://old.observation.org/waarneming/view/180811964

Can you tell me
1. Sea Squirt Class Ascidiacea Zakpijpen
https://www.inaturalist.org/observations/34031818
https://old.observation.org/waarneming/view/180811964
Green Sea Squirt (Didemnum molle), colony, corals, Bali, Lesser Sunda Islands, Bali Sea, Indonesia, Indian Ocean, Asia

2.Center of the Photo, the Green mat colonial tunicate (MantelDieren)
I am pretty certain they are in Didemnidae, as they share a common cloacal aperture as you say, but the branchial siphons (the small inhalant ones) do not seem to be in circular or linear systems. It is also more or less encrusting. As for this particular species, I've never seen it before.
A quick search suggests this may be Trididemnum miniatum, which forms "white to emerald or lime green" cushions (size to 1 cm)
The Australian Ascidiacea, Part 4:
https://www.biodiversitylibrary.org/page/40460926#page/273/mode/1up
Possible Image (B)
https://zookeys.pensoft.net/showimg.php?filename=oo_30408.jpg

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