1a |
With one or more tentacles
and a manubrium
(unless the specimen is damaged); size variable, but mature specimens generally
more than 2 mm high. |
2 |
1b |
With neither tentacles
nor a manubrium;
sexually mature specimens (with a fully developed gonad along each of the
4 radial canals)
less than 2 mm high |
Orthopyxis spp. |
2a |
Tentacles originating
at the margin of the bell |
3 |
2b |
Tentacles originating
decidedly above the margin of the
bell |
62 |
3a |
With not more than 4 tentacles |
4 |
3b |
With more than 4 tentacles |
17 |
4a |
|
|
4b |
|
|
5a |
|
|
5b |
|
|
6a |
|
|
6b |
|
|
7a |
|
|
7b |
|
|
8a |
|
|
8b |
|
|
9a |
|
|
9b |
|
|
10a |
|
|
10b |
|
|
11a |
|
|
11b |
|
|
12a |
|
|
12b |
|
|
13a |
|
|
13b |
|
|
14a |
|
|
14b |
|
|
15a |
|
|
15b |
|
|
16a |
|
|
16b |
|
|
17a |
Tentacles (usually
9) branched once or twice, one branch ending in a sucker, the other 1 or
2 branches having swollen clusters of nematocysts
at the tip and elsewhere |
Cladonema californicum |
17b |
Tentacles not
branched |
18 |
18a |
Radial canals
branching, with all branches reaching the bell
margin |
19 |
18b |
Radial canals
not branching (they may, however, have numerous lateral
diverticula) |
21 |
19a |
|
|
19b |
|
|
20a |
|
|
20b |
|
|
21a |
With 4 or 8 radial
canals |
23 |
21b |
With numerous radial
canals |
22 |
22a |
Bell up to 12 cm
wide; with up to 100 (or more) symmetrical radial
canals; in mature specimens all radial
canals reach the bell
margin; gonads extending along nearly the entire length of the radial
canals; up to 150 tentacles
in full-grown specimens, but the tentacles
are not all of the same size. (A common species) |
Aequorea victoria |
22b |
Bell up to 1.2 cm
wide; with fewer than 20 radial
canals, these not symmetrically arranged, and some of them not reaching
the bell margin; small
globular gonads attached to the radial
canals near the stomach; with more than 100 tentacles,
all the same size. (a rare species) |
Dipleurosoma typicum |
23a |
With 4 radial
canals |
28 |
23b |
With 8 radial
canals |
24 |
24a |
|
|
24b |
|
|
25a |
|
|
25b |
|
|
26a |
|
|
26b |
|
|
27a |
|
|
27b |
|
|
28a |
Tentacles evenly
distributed around the bell
margin |
34 |
28b |
Most tentacles
in clusters, although some single tentacles
may also be present |
29 |
29a |
|
|
29b |
|
|
30a |
|
|
30b |
|
|
31a |
|
|
31b |
|
|
32a |
|
|
32b |
|
|
33a |
|
|
33b |
|
|
34a |
Tentacles with
prominent rings of nematocysts
along their entire length (photo) |
35 |
34b |
Tentacles without
prominent rings of nematocysts
along their entire length |
37 |
35a |
Medusa nearly
disk-shaped, not deeply convex; bell
of mature specimens not more than 6 mm in diameter |
45 |
35b |
Medusa bell-shaped,
nearly hemispherical, bell
of mature specimens more than 1 cm in diameter |
36 |
36a |
Tentacles with
an adhesive pad located some distance proximal to the tip (photo),
and characteristically angled where the pad is located; without centripetal
canals; gonads orange, red, or brown |
Gonionemus vertens |
36b |
Tentacles without
an adhesive pad, but sometimes with a filamentous extension protruding
at an angle from the tip; usually with numerous subumbrellar
centripetal
canals; gonads usually pale pink or brown |
Eperetmus typus |
37a |
Radial canals
with conspicuous lateral
diverticula whose
length is at least twice the diameter of the canals |
38 |
37b |
Radial canals
without conspicuous lateral
diverticula
(if the margins of the canals are irregular, they do not form distinct
diverticula
whose length appreciably exceeds the diameter of the canals) |
40 |
38a |
Bell higher than
its diameter, or height and diameter nearly equal; gonads fingerlike, in
4 groups, attached to the radial
canals and hanging down into the subumbrellar
cavity |
Polyorchis penicillatus |
38b |
Diameter of bell
much greater than the height; gonads closely associated with the radial
canals and their diverticula,
not hanging down into the subumbrellar
cavity |
39 |
39a |
|
|
39b |
|
|
40a |
Diameter of bell
distinctly greater than the height; gonads associated with the radial
canals |
41 |
40b |
Height of bell greater
than the diameter, or height and diameter nearly equal; gonads associated
with the stomach |
53 |
41a |
With ocelli on
the tentacle
bulbs or on the marginal vesicles |
42 |
41b |
Without ocelli |
44 |
42a |
|
|
42b |
|
|
43a |
|
|
43b |
|
|
44a |
With tentacles
all the same size in mature specimens |
45 |
44b |
With tentacles
not all the same size in mature specimens |
52 |
45a |
Gonads ovoid or nearly spherical, occupying only a short section of
each radial canal; tentacles
more or less of fixed length (not highly extensile); diameter of bell
of mature specimens not more than 6 mm. |
46 |
45b |
Gonads elongated, associated with the radial
canals for a substantial portion of their length; tentacles
highly extensile, diameter of mature specimens more than 1 cm. |
47 |
46a |
|
|
46b |
|
|
47a |
With stomach attached directly to the subumbrella |
48 |
47b |
With stomach suspended on a gelatinous peduncle |
50 |
48a |
With up to 80 tentacles;
with 1-2 marginal vesicles
between each 2 tentacles,
each vesicle with
1 concretion |
49 |
48b |
With up to 350 tentacles;
with a total of 16-24 marginal vesicles,
each with numerous concretions;
lips of mouth long and extended |
Mitrocoma cellularia |
49a |
Gonads not usually mature until diameter of bell
is greater than 1.5 cm; gonads, when sectioned transversely, with an elliptical
outline; gonads usually light-colored but may have a stripe of dark pigment
running lengthwise; bell
margin may have a ring of dark pigment; up to 20 tentacles
per quadrant at maturity. (Phialidium gregarium in original key) |
Clytia gregaria |
49b |
Gonads mature by the time the bell
reaches a diameter of 1 cm; gonads, when sectioned transversely, with a
circular outline; gonads usually fairly dark brown in color (brown, gray,
or yellowish); bell
margin without a ring of dark pigment; less than 10 tentacles
per quadrant at maturity. (Phialidium lomae in original key) |
Clytia lomae |
50a |
|
|
50b |
|
|
51a |
|
|
51b |
|
|
52a |
With up to 64 large tentacles
and 5-9 small tentacles
or cirri between each two large tentacles;
ring canal and gonads usually pale rose-pink;
exumbrellar
surface smooth and regular |
Mitrocomella polydiademata |
52b |
With up to 350 tentacles,
long and short ones more or less alternating; colorless, or with the gonads
and/or the exumbrella
pale blue; exumbrellar
surface irregularly creased |
Mitrocoma cellularia |
53a |
With more than 50 marginal tentacles |
54 |
53b |
With fewer than 50 marginal tentacles |
55 |
54a |
With a large, bulbous apical projection that is somewhat pinched off
from the rest of the bell;
with up to 150 marginal tentacles;
each with a black ocellus
and some red or orange pigment on its bulb; bell more or less opaque |
Catablema multicirrata |
54b |
Apical projection low and rounded, not at all pinched off from the
rest of the bell; with
up to 100 or more marginal tentacles,
these without ocelli;
manubrium
and tentacle bases
usually orangish, bell
not opaque |
Neoturris brevicornis |
55a |
|
|
55b |
|
|
56a |
|
|
56b |
|
|
57a |
|
|
57b |
|
|
58a |
|
|
58b |
|
|
59a |
|
|
59b |
|
|
60a |
|
|
60b |
|
|
61a |
|
|
61b |
|
|
62a |
|
|
62b |
|
|
63a |
|
|
63b |
|
|
64a |
|
|
64b |
|
|
65a |
|
|
65b |
|
|