THE STEINHART AQUARIUM - Gulf of Guinea Science ...

50 A Docent Field Guide to the Species of the Steinhart Aquarium
eastern and southern Caribbean; rare in the
northwestern Caribbean.
Habitat: Shallow reef areas with mild to strong
currents; prefer strong light and water flow.
Appearance: A large, green to whitish, carpetlike
sea anemone. The oral disc covered by
many short tentacles with rounded tips. Max.
diameter: 15 cm.
Diet: Nutrition mainly from photosynthetic
zooxanthellae. Also actively collect small
invertebrates and fish with their tentacles. The
amount of food they eat determines how fast
they grow.
Reproduction and Development: Sexes
separate; release eggs and sperm into the water.
Can reproduce asexually through splitting ad
budding. May occupy large areas in dense
aggregations.
Remarks: Research suggests a peptide molecule
found in a toxin produced by the sun anemone
may have pharmacological value in the treatment
of such various conditions as type-2 diabetes and
autoimmune diseases in humans.
Miniature Carpet Anemone
Stichodactyla tapetum (Stichodactylidae)
Distribution: Indian and Pacific Oceans, Red Sea.
Habitat: In rock crevices on fringing coral reefs;
also on sand, mud or rock of reef shallows in
areas of moderate water flow.
Appearance: Tentacles short, bulbous, densely
packed. Often arrayed in fields on the entire
disc.
Diet: Primarily by-products of symbiotic
zooxanthellae as well as drifting plankton.
Reproduction and Development: Sexual
reproduction. Members of this family rarely
divide in captivity.
Remarks: Tentacles deliver a potent sting for
their size.
Some species of Stichodactyla anemones host
anemone fish. This species does not.
CLASS SCYPHOZOA
(TRUE JELLYFISH)
Moon Jelly
Aurelia aurita (Ulmaridae)
Distribution: Widespread. Atlantic, Arctic,
Pacific, and Indian Oceans.
Habitat: Moon jellies are found near coastlines;
they can survive over a wide range of
temperatures (-6 °C to 31 °C; optimum 9 °C to
19 °C). They can also live in brackish waters.
They inhabit both oceans and inshore seas,
often in large numbers.
Appearance: Size range between 5 and
40 cm. Delicate coloration. Lack the long,
potent stinging tentacles seen in some other
jellyfishes.
Diet: A. aurita feeds on plankton. A mucous
layer traps small organisms on the jellyfish’s
surface. Flagellae move the food from point
of capture along well defined paths to the
animal’s stomach.
Reproduction and Development: Males and
females are distinct and reproduction is sexual.
Sexes can be distinguished since females hold
the fertilized eggs, which appear as whitishgray
clumps on the manubrium (the conical
mass that extends from the undersurface of
the jellyfish.) Males may sometimes be seen
with long sperm filaments trailing from the
oral arms. After fertilization there are several
distinct larval forms as the organism develops
from egg to adult.
Mortality/Longevity: The death of the organism
may follow reproduction, which leaves the
gonads open to infection and degradation.
Documented predators include the ocean
sunfish, the leatherback sea turtle, and a few
species of larger jellies. They are also hunted
by birds. They are relatively defenseless, since
they do not have tentacles that sting. A. aurita
is a food item in many Asian and Southeast
Asian countries.
Upside-down Jellyfish
Cassiopea andromeda (Cassiopeidae)
Distribution: Native to Indo-Pacific, but
introduced in Caribbean, southern Florida,
Hawaii, and elsewhere.
Habitat: Upon shallow substrates, typically
in calm sandy areas, often around mangroves.
Intertidal to 10 m.
Appearance: To 30 cm diameter, disc-shaped bell
has elaborately fringed oral arms. Coloration
is gray, brown or green with triangular white
blotches surrounding the bell.
Diet: Symbiotic algae in its tissues provide