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Digitate Hydroid
(Class: Hydrozoa, Zanclea sp.?)
(Class: Hydrozoa, Zanclea sp.?)
In post #51 you can see a hydroid in its medusoid form (jellyfish-like).
I was fortunate enough to find a different hydroid form in my tank today. Usually it is impossible to find these things in older tanks, but since I have upgraded tanks these things pop up again.
You might have seen these white or transparent tentacles in your tank. They like to attach to reef rock and irritate corals:
(Semi-Transparent "tentacle" moving in the current)
BRS has a better image which they attribute to Reef2Reef, but I did not find the original source yet.
| Common Name | Digitate Hydroid |
| Classification | Class: Hydrozoa, Zanclea sp.? |
| Verdict | Attention (can irritate corals) |
| Size | ≤ 15cm (6") |
| Found | Rockwork, Filter sump |
| Rarity | Common (new tanks), Rare (old tanks), can be introduced on live rock and coral frags, etc. |
(The very same tentacle under a microscope)
(Hydroid Polyp - 10x40 PL APO Immersion-Oil Objective)
(Polyp Focus Stack - 10x40 PL APO Immersion-Oil Objective)
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