ANIMAL TAXONOMY

1. PHYLUM
CNIDARIA
Presented by:
Gabitan, John Paulo
Tero, Nariza L.
Valencia, Juliet D.
Zapanta, Schola Marie

3. • Radially symmetrical cnidarian body is
organized as a hollow sac with the mouth and
surrounding tentacles located at one end.
• Based on molecular data, some systematists
have proposed that cnidarians share a
common ancestor with the clade of bilateral
animals.
• Cnidarians have two body shapes: polyp and
medusa.
• Polyp form, represented by hydra, typically
has dorsal mouth surrounded by tentacles.
• Medusa form, the mouth is located in the
lower concave or oral surface; the convex
upper surface is the aboral surface.

4. • Cnidarians get their name from specialized
cells called cnidocytes that contain stinging
organelles.
• It is found mainly in epidermis especially on
tentacles.
• Cnidocytes contain stinging “thread capsule”
called nematocysts
• Cnidarians use their tentacles to capture prey
and they push it into the mouth and it leads
to gastrovascular cavity, where digestion
takes place.
• Mouth is the only opening into gastrovascular
cavity that serves for both ingestion of food
and expulsion of undigested material. Gas
exhange and excretion occur by diffusion.

5. • Cnidarians are diploblastic meaning thay
have 2 definite tissue layers.
• Ectoderm which give rise to outer (covering
of body) and endoderm gives rise to inner
gastrodermis, which lines the gastrovascular
cavity and functions in digestion.
• These thin layers are separated by a thick,
jellylike mesoglea, which is mainly
acellular.
• Cnidarians have nerve cells that form nerve
nets connecting sensory cells in the body
wall to contractile cells and gland cells.
• Hydrostatic skeleton supports the body
and allows movement.

7. GROUPS
HYDROZOANS
SCYPHOZOANS
CUBOZOANS
ANTHOZOANS

8. HYDROZOANS
HYDRA
• Mainly marine but
some are freshwater
species
• Alternation of polyp
and medusa stages in
most species (polyp
form only in Hydra)
• Some form colonies

9. SCYPHOZOANS
• “True” jellyfish
• Mainly marine
• Typically inhabit
coastal water, free
swimming medusa
most prominent
form
• Polyp stage is often
reduced
JELLYFISH

10. CUBOZOA
BOX
JELLYFISH
• Inhabit tropical and
subtropical waters
• Have polyp stage
but medusa form
most prominent
• Square shape when
viewed from above
• Actively hunt prey
• Complex eyes that
form blurred
images

11. ANTHOZOA
SEA
ANEMONES
• Marine
• Solitary or colonial
polyps
• No medusa stage
in most
• Gatrovascular
cavity divided by
partitions into
chamber,
increasing area for
digestion

12. REPRESENTATION ORGANIZATION

13. ECONOMIC IMPORTANCE
• Coral reefs (Anthozoans) serves as a habitat
of fishes and this may also serve as a tourist
attraction to humans.
• They also provide a home for algae which
creates oxygen that we breathe. The coral
reefs are also important because the polyps,
algae, and animals in that habitat are a
major food source for other animals.