taxons and orthography

[Peter Schuchert]

dear collegues
English is not my mother tongue, so could you please give me some advice on
the correct usage of articles and taxon names? Are taxon names used with or
without articles ?
Are taxon names used in plural or singular? In the literature I found both
usages.
So, whhat is the correct version in the following examples:

Cnidaria are mostly marine animals ....
The Cnidaria are mostly marine animals ....

germ cells are lodged in the gastrodermis in Anthozoa and Scyphozoa ...
germ cells are lodged in the gastrodermis in the  Anthozoa and Scyphozoa ..

... nematocysts are found in the Cnidaria only ...
... nematocysts are found in Cnidaria only ...

The Medusozoa are the sister group of the Anthozoa ...
Medusozoa is the sistergroup of Anthozoa ...
The Medusozoa is the sister group of the Anthozoa ...



many thanks for your advice,
Peter
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Peter Schuchert
Museum d'Histoire Naturelle
1 Route Malagnou
CH-1211 Geneva
Switzerland

http://www.geneva-city.ch/musinfo/mhng/
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