245 research outputs found
On the classification of the genera Labyrinthula, Schizochytrium and Thraustochytrium (Labyrinthulids and Thraustochytrids)
Species of the genera Labyrinthula, Schizochytrium, Thraustochytrium and related organisms have recently attracted attention in biotechnology, and here is a short note on how to classify these rather special organisms
Triassic Leech Cocoon From Antarctica Contains Fossil Bell Animal
This is the publisher's version of this article, which has been shared with permission. The article is also available from: http://dx.doi.org/10.1073/pnas.1218879109Our understanding of the evolution of life on Earth is limited by
the imperfection of the fossil record. One reason for this imperfect
record is that organisms without hard parts, such as bones, shells,
and wood, have a very low potential to enter the fossil record.
Occasionally, however, exceptional fossil deposits that preserve
soft-bodied organisms provide a rare glimpse of the true biodiversity
during past periods of Earth history. We here present an extraordinary
find of a fossil ciliate that is encased inside the wall
layer of a more than 200 Ma leech cocoon from Antarctica. The
microfossil consists of a helically contractile stalk that attaches to
a main body with a peristomial feeding apparatus and a large Cshaped
macronucleus. It agrees in every aspect with the living bell
animals, such as Vorticella. Vorticellids and similar peritrichs are
vital constituents of aquatic ecosystems worldwide, but so far have
lacked any fossil record. This discovery offers a glimpse of ancient
soft-bodied protozoan biotas, and also highlights the potential of
clitellate cocoons as microscopic “conservation traps” comparable
to amber
Arguments against the proposal 2302 by John & al. to reject the name Gonyaulax catenella (Alexandrium catenella)
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