Wild creatures with spoon limbs (Genus Ramazzottius)
Possibly you did already come across the tardigrade Ramazzottius oberhaeuseri
with its tiger pattern under your microscope. It is quite abundant and can be recognized easily.
Some years ago we have presented a beautiful color portrait
here in the Water Bear web base. In real life, simply photographed it looks
as shown just below:
Water bear Ramazzottius oberhaeuseri
(previous name: Hypsibius oberhaeuseri), female.
Some ovary cells and their nuclei are perceivable.
Typical body length ca. 300 µm.
Even at moderate magnification we can distinguish the
red-brown bands and the unymmetrical claws, each of them with a long
Ramazzottius oberhaeuseri doesn't hhave eye pigment spots. By the way: up to the present
day it is not known why those tardigrades without eyespots move as smoothly
and well-controlled as their brothers ans sisters which have eyespots.
The buccal system is rather small, the buccal tube short and narrow.
The four visible macroplacoids are arranged symmetrically a the sphaeroid pharynx .
Ramazzottius oberhaeuseri, anterior part of the body.
Image width ca. 100 µm.
Ramazzottius oberhaeuseri has some exotic relatives which look a little
bit more wild; in fact their temperament causes some problems in photography.
Nevertheless our CCD has caught a fraction of their character.
A Ramazzottius sp. tardigrade.
Dark field illumination is well suited in order to show the transparency
of the body and the band pattern. This species has longer claws than
those of the "classic" Ramazzottius oberhaeuseri.
Tardigrade Ramazzottius sp.
Dark field illumination.
Focus on the backside pattern.
The same species in bright field
illumnation. Note the extremely long legs and claws.
The Ramazzottius tardigrades have extra-long claws that can be
bent only in one direction. It looks a little bit like the finger movement
of a smoker who is disposing his ash (though, of course, we do have only
strict non-smokers under water).
at a tardigrade leg, in this case photographed on an old cuticula after moulting.
Please note the spoon type limb. In position a) the claw
can only bend ti the left. And what do you think about the scar at b)
an intentional breaking point?
Just compare the situation at a) with an ordinary spoon.
You will note that it can bend only in one direction.
Soft plastic spoon, before experiment.
Soft plastic spoon, bent a little bit
into the only possible direction.
Soft plastic spoon, bent stronger
into the only possible direction. Bending into the opposite direction
is virtually impossible. Just give it a try but play safe and use your
own private spoon ...
Of course one might discuss the pros and cons of this spoon limb.
Possibly it is just some kind of semi-automatic moss grip making optimum
contact with the moss substrate one one hand but not impeding smooth
movement in a moss jungle on the other.
Live and survival in the moss jungle is so much complicated - you can't imagine.
But this text might help a little bit:
Hartmut Greven, Lutz Schüttler: How to Crawl and Dehydrate on Moss.
Zoologischer Anzeiger, vol. 240 (2001) p. 341 - 344.
© Text, images and video clips by
Martin Mach (firstname.lastname@example.org).
Water Bear web base is a licensed and revised version of
the German language monthly magazine Bärtierchen-Journal .
Style and grammar amendments by native speakers are warmly welcomed.