Thai tardies (I)
As you will be able to figure out, the travelling budget of a free online
magazine like the Water Bear Web Base as a rule will be limited. Instead,
we do receive samples from our friends and readers from time to time.
Recently a married couple sent us some ocean sand/water samples from Thailand and
we are quite happy to report the results here.
The samples came from a beach of the Marriott Hotel near Hua Hin. You will be
able to trace the locality just by copying the following coordinates
to the Google Maps® command line:
Obviously, it appears that a few hotels have been built in this region during
the last decades, but we know that the tardigrades don't care so much about
the human annoyance. An old engraving as depicted below shows a much less-inhabited
scenery in the same region with fishermen specialising on holothurians (sea cucumbers).
We can be sure that they definitely were not aware of the presence of
Tetrakentron synaptae on the mouth tentacles of the holothurians
(Tetrakentron synaptae is one of the very few parasitic tardigrade species).
Fishermen in Siam (today: Thailand) specialising on holothurians. Engraving from 1863.
The illustration was first published in Henri Mouhots diary "Voyages dans les royaumes
de Siam ... 1858-1861" (published in 1863) and is assumed to be based on
the very first photographs of this region. It was not possible to print
photographs properly at this time, so the photographs had
to be converted into engravings like this one.
Of course we didn't want to cut the tentacles of
peaceful creature like the holothurian just in order to find some tardigrades.
Besides it would have been complicated to transport the holothurian
in fresh state by airplane. So it was quite clear that our classical
sampling method with a little bit of sand and sea water in a plastic film container
had to be used. Below you will perceive the content of this film container
as documented by means of a computer flatfed scanner.
The sand/seawater sample.
Image taken by means of a flatbed scanner.
When using a stronger magnification, the fine sand samples
can be better investigated and measured:
The same sand sample, as seen in under a "real microscope", in transmitted light.
As usual, now the tedious search for the tardigrades
followed. After a few hours of searching we came across a first Batillipes cuticula!
Up to this moment we had never found a freely floating isolated cuticula.
This empty cuticula clearly indicates that some tardigrades
are around (or at least were around recently).
Please note the long crack at the top side of the cuticula
marking the "moulting exit" of the tardigrade.
With a cuticula there are reasons to hope that some tardigrades might be close!
We will show them in the next issue.
© 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
Style and grammar amendments by native speakers are warmly welcomed.