As with all thecate
of this species is partly enclosed by a hydrotheca.
is bell-shaped and deeper than wide, and able to contain the entire hydranth
when it contracts. There is no operculum.
The rim of the hydrotheca
is smooth and a diaphragm exists in the lower part of the hydrotheca.
on slender, annulated individual stalks (pedicels) (see photo above)
The colony produces small medusae
(<= 2 mm) that may or may not be released. The medusae
have no stomach.
everta (Clark, 1876)
Subclass Leptotheca (Leptomedusae;
everta, about 2
mm tall, on a tunicate. Note the annulated pedicel and smooth
to the hydrotheca.
|(Photo by: Dave
Cowles, August 2010 )
How to Distinguish from
Several similar genera such as Campanularia
have cusps or
undulations on the rim of the hydrotheca. Orthopyxis
compressa and O.
have smooth, non-annulated pedicels
to southern California.
Sometimes found abundantly on
grow in a stolon.
its gametes. The larvae of the pycnogonid Tanystylum
duospinum live parasitically on this species.
1987, 1996 (as Orthopyxis
General Notes and
abundances, unusual behaviors:
Another indivudual on the same tunicate. Note the
to some stalks.
Authors and Editors of Page:
Dave Cowles (2010): Created original page
CSS coding for page developed by Jonathan Cowles (2007)
Rosario Invertebrates web site provided courtesy of Walla