| 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 |
With 2 tentacles,
or 2 pairs of tentacles,
situated on opposite sides of the bell
(there may also be rudimentary tentacles
elsewhere on the bell
margin) |
5 |
| 4b |
Arrangement of tentacles
not as described in choice 4a |
7 |
| 5a |
|
|
| 5b |
|
|
| 6a |
|
|
| 6b |
|
|
| 7a |
With 3 or 4 tentacles,
each originating from a separate tentacle
bulb |
8 |
| 7b |
With 1 to 4 tentacles
originating from a single tentacle
bulb (medusae
are also produced asexually from this bulb)
(with 3 other rudimentary tentacle
bulbs, and with 5 exumbrellar
nematocyst
tracts
running from the tentacle
bulbs toward the apex) |
Hybocodon prolifer |
| 8a |
With 3 tentacles
when mature (but medusae
less than 2 mm high may have only 1 tentacle) |
9 |
| 8b |
With 4 tentacles
(many small medusae
with 4 tentacles
are young Anthomedusae or Leptomedusae that will have more tentacles
when they mature; immature stages are usually difficult to identify and
will not be dealt with in this key) |
10 |
| 9a |
|
|
| 9b |
|
|
| 10a |
Diameter of the bell
decidedly greater than the height; with 8 marginal
vesicles, each with a black ocellus,
spaced evenly around the bell
margin |
young specimen of Tiaropsidium
?kelseyi |
| 10b |
Diameter of bell
not greater than the height; without marginal
vesicles, but there may be ocelli
on the tentacle
bulbs |
11 |
| 11a |
Tentacles
with
swollen clusters of nematocysts
along their entire length, in addition to a terminal swelling |
12 |
| 11b |
Tentacles
with
only a terminal swelling in which nematocysts
are concentrated (scattered nematocysts
may also occur in the tentacles,
but they are not in swollen clusters) |
16 |
| 12a |
With a red or black ocellus
on each tentacle bulb; manubrium
of variable length |
13 |
| 12b |
Without ocelli,
although tentacle bulbs may be red; manubrium
not reaching the level of the margin of the bell
and often with bright red pigment |
Euphysa flammea or Euphysa
japonica |
| 13a |
Bell
narrow and
conical, its height up to twice the diameter; height up to 4 cm, but
usually
not over 2 cm (rare) |
Sarsia princeps |
| 13b |
Height of bell
only
slightly greater than the diameter; height usually less than 1.5 cm. |
14 |
| 14a |
Bell
of mature medusa
up to 8 mm high; tentacle
bulbs and manubrium
brilliant iridescent green (the proximal portion of the manubrium,
which lacks gonads, extends to the level of the bell margin) |
Sarsia viridis |
| 14b |
Bell
of mature medusa
more than 8 mm high; tentacle
bulbs and manubrium
not brilliant iridescent green, but may be some other color. |
15 |
| 15a |
In relaxed specimens, proximal portion of the manubrium
(the portion without gonads) extends at least to the level of the
margin
of the bell;
with 4
exumbrellar
nematocyst
patches
in each quadrant (2 near the margin of the bell
and 2 about one-third the distance from the apex to the margin)
(common,
undescribed) |
Sarsia sp. |
| 15b |
In relaxed specimens, proximal portion of the manubrium
(the portion without gonads) less than one-half the height of the bell;
without exumbrellar
nematocyst
patches,
although young specimens may have scattered exumbrellar
nematocysts
that
disappear by maturity (common) |
Sarsia
tubulosa |
| 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 |
Gonads sausage-shaped, hanging freely into the subumbrellar
cavity from near the proximal portions of the radial
canals |
25 |
| 24b |
Gonads not hanging freely, but attached for most
or all of their length
to the radial
canals |
26 |
| 25a |
Height of bell about twice the diameter; stomach
suspended on a long
peduncle |
Aglantha
digitale |
| 25b |
Height of bell about equal to the diameter;
stomach attached to the
roof of the subumbrella
(rare) |
Crossota sp. |
| 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 |
With ocelli
on
some or all of the tentacle
bulbs; without marginal
vesicles, but with short marginal clubs (rare) |
Laodicea sp. |
| 42b |
Without tentacularocelli;
with 8 marginal
vesicles, each with a black ocellus |
43 |
| 43a |
With about 300 short tentacles,
these all alike; lips of mouth much folded and crenulated |
Tiaropsis multicirrata |
| 43b |
With 8 large tentacles
and up to 128 rudimentary tentacles;
lips of mouth slightly frilled (rare) |
Tiaropsidium
kelseyi |
| 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 |
With up to 100 or more tentacles,
these having prominent rings of nematocysts
along their entire length; with a central, pedent
manubrium;
gonads along the 4 radial
canals |
Eperetmus typicus |
| 62b |
With less than 40 tentacles,
these lacking rings of nematocysts;
with a broad stomach and peripheral stomach pouches, the latter having
gonads on their walls; without radial
canals |
63 |
| 63a |
With 4 tentacles,
and usually 8 stomach pouches |
Aegina citrea |
| 63b |
With more than 4 tentacles,
and an equal number of tentacles
and stomach pouches |
64 |
| 64a |
With marginal statocysts
and otoporpae (bristly tracts that run a short distance up the exumbrella
from the margin |
Cunina sp. |
| 64b |
With marginal statocysts
but without otoporpae |
65 |
| 65a |
With 8-20 (usually 16) tentacles
and stomach pouches; each marginal lappet
with up to 20 statocysts |
Solmissus
marshalli |
| 65b |
With 20-40 tentacles
and stomach pouches; each marginal lappet
with 2-5 statocysts
(rare) |
Solmissus incisa |