Marine Worms
Flatworms, Nematodes, Annelids,
General Characteristics of
Marine Worms
bilateral symmetry
 Cephalization (Has a head)
 Hydrostatic skeleton (no bones)
 most are benthic
2 types
No body cavity=flatbodies
 _No_ segments, No_ circulatory
system, No Respiratory system
 _Type 1_:Turbellarians (Non
 _Type 2_: flukes and
tapeworms (parasitic)
Swimmers itch
Most turbellarians are
detect prey
unique prey-capturing
– _Stab__
– _Suffocate_
pharynx secretes enzymes
and pulls in food
food is digested in the
gastrovascular cavity =
which functions as a
mouth and an anus__.
– _Asexually through regeneration
– _Sexually_: Penis Fencing (flatworms are male and
female. They fight with their penis’s the winner
becomes the male, looser becomes the female)
_round worms, tapered at both ends
_No segments___
_They have a body cavity_: Hence why round in
__Most numerous animals on the planet__
– Handful of sediment may contain 3 million
Nonparasitic species are scavengers and are
small in size__
 Parasitic and carnivorous species are larger_:
Bodies divided into _Segments_
↑ common marine polychaetes
Has _a closed circulatory system__
↓ deep sea vent tube worms
“more advanced” worm
Setae: used for locomotion and defense
Polychaetes (Not a bird)  are the main
type of marine worm: For example,
earthworm is an annelid, but it is not a
← errant polychaete
Polychaetes Annelids 2 Types:
– _Type 1: Sedentary polychaetes that burrow or
built tubes of sand, calcium carbonate, proteins.
They filter feed_with cilia that extend from
tubes and the aid of chemoreceptors.
My Favorite
Sedentary Polychaetes:
_Christmas Tree Worms_;
Also used in Avatar; IN Real Life
Use their gills to capture plankton
Polychaetes Annelids 2 Types:
Type 2: _Errant (swim)_polychaetes have jaws
with teeth_ and nocturnally hunt small
invertebrates. Many are poisonous and have a
painful bite.
Sexual Reproduction in
_Epitoky_ is a form
of reproduction ,The
worms undergo a
transformation into an
_Epitoke, a pelagic
morph capable of
_Sexual Reproduction.
Often an epitoke is the
end part of the worm,
which separates from
the head. The end
then releases the eggs
or sperm.
Other Marine Worms
_Peanut Worms_: Filter Feeder that
burrows in the sand, sticking out its head
to feed
Other Marine Worms
_Spaghetti worms__: lies hidden in
sediment or rocky crevices while its foodgathering tentacles wave overhead.
Other Marine Worms
Fire worms have bristles that are filled with
venom and easily break when touched to
discourage predators. They also inflict a
painful rash on any human who handles them
Aliens or Marine Worms?
New Species, of marine worms
Yet still to be named……..
Marine Worms
1.Name the three types/classifications of worms
2.List them from simple to complex
3.List three characteristics of each type of worm
4.Give two examples of sexual reproduction for
5.Describe two ecological roles of marine worms.
6.What is swimmers itch?
7.Define: Sedentary, Cephalization, Benthic, Errant,
Polychaete and gastrovascular cavity