Key: Class Scyphozoa
Scyphozoans share the following characteristics: Medusa
form dominates the life cycle, and some do not have a polyp
stage. The medusae
may be large, are often colored (often red, orange, or yellow), do not
have a velum.
margins of the bell are usually lobed into lappets
and do not usually have a ring
canal. Sense organs are usually found in the
is not usually on an extended manubrium. The gut is divided
4 branches by mesenteries. Cnidae are present in both the
and the gastrodermis. Polyps, if present, are small and
The polyps produce medusae
by asexual budding (strobilization).
Key written by Dave Cowles
|| Motile medusae,
not attached to the substrate by a stalked adhesive disk which arises
attached to the substrate by a stalked adhesive disk which arises from
has a central
mouth which arises from the subumbrella
has no central
mouth. Frilled edges of the oral lobes block mouth
tiny openings on 8 branching armlike appendages on the subumbrella
open into gut. Have no marginal tentacles.
||Bell of medusa
than wide, divided into upper and lower region by a groove which
Bell margin deeply scalloped into pedalia
from which the tentacles,
arise. Small to moderate in size; mostly bathypelagic
||Bell of medusa
or may not be taller than wide, but is not divided into an upper and
region by a groove circling the exumbrella.
Margin of bell often has lappets
but is not deeply scalloped into pedalia.
The corners of the mouth are drawn out into four gelatinous, frilly
are hollow and contain extensions of the radial
canals. Includes most of the common temperate and
Mostly moderate to large in size.
in This Key:
Page created by Dave Cowles, 2011