Phylum:
annelida
Class:
polychaeta
Genus:
Arenicola
The lugworm (Arenicola) us a polychaete with reduced parapodia
Phylum:
annelida
Class:
polychaeta
Genus:
Nereis
This example of a polychaete is commonly called the clamworm or sandworm. Most annelids are polychaetes. They are marine and have gill-like structures called parapodia that have many setae.
Phylum:
annelida
Class:
polychaeta
Genus:
nereis
This slide shows a parapodium of the clamworm Nereis. These structures are the first respiratory organs you have encountered.
Phylum:
annelida
Class:
oligochaeta
Genus:
lumbricus
Species:
terrestris
Name means "few bristles".
Primarily freshwater and moist terrestrial habitats.
Head poorly developed or absent.
Clitellum present.
Hermaphroditic, but mating involves the exchange of sperm between 2 individuals. Do not self fertilize.
Phylum:
annelida
Class:
hirudinea
All leeches belong to the Class Hirudinea. As would be expected. there are many different kinds of leeches. Leeches are both parasitic and predaceous animals. They are closely related to members of the Class Oligochaeta
Phylum:
Mollusca
Class:
Polyplacophora
Genus:
Katharina
The shell of chitons is composed of 8 overlapping dorsal plates. Located on the ventral surface are the large foot and the gills located in the mantle cavity.
Phylum:
Mollusca
The radula is a rasping organ used to remove algae and other materials from the substrate on which the animal lives. The radula consists of rows of chitinous teeth. The organ is found in all mollusks except the bivalves (members of the Class Pelecypoda)
Phylum:
mollusca
Class:
scaphopoda
Marine mollusks.
Tubular shell. Inside the shell the mantle wraps around the visceral mass.
No head; reduced foot.
Phylum:
mollusca
Class:
cephalopoda
Genus:
Nautilus
Chambered Nautilus shell
The chambered Nautilus is the only cephalopod that secretes an external calcium carbonate shell. It is beleived to be a more primitive member of this class.
Phylum:
Nemertea
Species:
Cerebratulus
Members of this phylum are commonly called ribbon or proboscis worms. They have many features similar to the flatworms (Phylum Platyhelminthes) All ribbon worms are marine. This common form is Cerebratulus. The most diagnostic featuer of these worms is their proboscis at the anterior end. The proboscis is used for prey capture. Some specimens will not have the proboscis extended, and not all ribbon worms have proboscis
Phylum:
Platyhelminthes
Class:
Turbellaria
Genus:
Bdelloura
This slide of Bdelloura shows the highly branched digestive system. Bdelloura is a marine commensal that lives on the gills of the horseshoe crab.
Phylum:
Platyhelminthes
Class:
Trematoda
Genus:
Schistosoma
Species:
mansoni
This is the blood fluke Schistosoma
mansoni. The final host is a human. The disease schistosomiasis is caused by this worm and is one of the major killers of man. The animals in view are a male and female copulating. Unlike most flukes, schistosomes are dioecious.
Phylum:
Platyhelminthes
Class:
Cestoda
Genus:
Taenia
Species:
pisiformis
This is the scolex or holdfast of Taenia pisiformis, one of the most common tapeworms of dogs and related wild carnivores. The worm seldom occurs in cats. Note the hoods and suckers on the scolex; these are used to attach the worm to the wall of the gut. Pork tapeworm (Taenia solium) also have hooks and suckers on the scolex.
Phylum:
Platyhelminthes
Class:
Cestoda
Genus:
Taenia
Species:
pisiformis
A gravid proglottid, like this one, consists of an expanded uterus filled with eggs. There may be 80,000 eggs in one gravid proglottid.
Phylum:
Platyhelminthes
Class:
Cestoda
Genus:
Taenia
Species:
solium
cysticercus pictured, the encysted form of the pork tapeworm.
