Pszemol
March 28th 04, 04:47 AM
I have one Tridachia crispata in my tank and I was always
curious in how this boneless, soft animal consumes algae...
I have never seen it on the glass scraping algae with its
spatula like all other, regular snails do (i.e. Astrea, Nerite).
Today I caught it near the side glass, at the patch of green
hair algae... So I run for my stamp loupe (magnifier glass)
and started staring at this beautifull creature...
Finally I could observe the nature of its pearl colourfull
egdes of its body: green patches gradualy become dark blue
and then orange to become totaly transparent at the edge...
But back to eating: Hair algae under 10x magnification look
like long tubes filled with transparent, green liquid...
Lettuce slug's technique of eating algae is very interesting:
It aproaches a single hair with its soft mouth and hugs it
with its lips. Then you can notice like puncturing the cell wall
of the algae and it starts sucking out the green fluid from the
algae. When the walls of the algae body collapse, snail fills
it back with water (saliva?) and goes back to sucking...
You can clearly see grean parts of algae body intermixed with
transparent or whitish saliva flowing in sucking action to
the slug mouth. Sucking and refills repeat many times.
It is obvious from the observation, that many hairs of the
algae are connected with each other, and snail (nudi) empties
2-4 hairs at once, doing only one injection/entry...
Unfortunately, Lettuce Nudibranch does not eat the whole algae,
so after its feast it leaves transparent, nicely cleaned
and flushed from inside completely emptied threads of algae.
I can only guess it is deadly for algae, but I have no idea
how quickly algae can regenerate from this. Since I marked
the location of todays feast I will observe how the algae
will look in a couple of days...
Now I wonder - if this slug eats hair algae only it can be
destined for starvation in clean tanks without hair algae...
curious in how this boneless, soft animal consumes algae...
I have never seen it on the glass scraping algae with its
spatula like all other, regular snails do (i.e. Astrea, Nerite).
Today I caught it near the side glass, at the patch of green
hair algae... So I run for my stamp loupe (magnifier glass)
and started staring at this beautifull creature...
Finally I could observe the nature of its pearl colourfull
egdes of its body: green patches gradualy become dark blue
and then orange to become totaly transparent at the edge...
But back to eating: Hair algae under 10x magnification look
like long tubes filled with transparent, green liquid...
Lettuce slug's technique of eating algae is very interesting:
It aproaches a single hair with its soft mouth and hugs it
with its lips. Then you can notice like puncturing the cell wall
of the algae and it starts sucking out the green fluid from the
algae. When the walls of the algae body collapse, snail fills
it back with water (saliva?) and goes back to sucking...
You can clearly see grean parts of algae body intermixed with
transparent or whitish saliva flowing in sucking action to
the slug mouth. Sucking and refills repeat many times.
It is obvious from the observation, that many hairs of the
algae are connected with each other, and snail (nudi) empties
2-4 hairs at once, doing only one injection/entry...
Unfortunately, Lettuce Nudibranch does not eat the whole algae,
so after its feast it leaves transparent, nicely cleaned
and flushed from inside completely emptied threads of algae.
I can only guess it is deadly for algae, but I have no idea
how quickly algae can regenerate from this. Since I marked
the location of todays feast I will observe how the algae
will look in a couple of days...
Now I wonder - if this slug eats hair algae only it can be
destined for starvation in clean tanks without hair algae...