What are the two subclasses of Clitellata?

What are the two subclasses of Clitellata?

Systematics. According to modern phylogenetic analyses, the Clitellata are considered to be a monophyletic clade embedded deep in the polychaetes. The group is divided into the subclasses Oligochaeta and Hirudinea.

Are Clitellata hermaphroditic?

Clitellates are hermaphrodites (i.e., individuals containing both male and female reproductive structures) and both male and female gonopores exit from the clitellum. …

How many species of annelids are there?

15,000
There are about 15,000 known modern species of annelids….Annelid.

Kingdom: Animalia
Phylum: Annelida Lamarck, 1809

What do Clitellata worms eat?

Most oligochaetes feed by ingesting sediment, but several North American genera prey on other worms or on a variety of small invertebrates. Branchiobdellidans or crayfish worms are leech-like ectosymbionts living primarily on astacoidean crayfish.

Is a millipede an annelid?

The Annelid phylum contains three classes of organisms: Polychaeta, Oligochaeta and Hirudinea. The Arthropoda phylum contains five classes: Crustacea (shrimp and lobster), Arachnida (spiders and scorpions), Chilopoda (centipedes), Diplopoda (millipedes) and Insecta (roaches and beetles).

What are Pseudohearts?

Lateral hearts, also known as pseudohearts or commissural vessels, are blood vessels on either side of the alimentary canal of some annelids that pump blood from the dorsal vessel to the ventral vessel. The lateral hearts of Lumbricus terrestris are located in body segments 6–11.

What clitellum means?

Definition of clitellum : a thickened glandular section of the body wall of some annelids that secretes a viscid sac in which the eggs are deposited.

Where is the clitellum located on a clitellate annelid?

Unlike the class of Polychaeta, they do not have parapodia and their heads are less developed. Clitellate annelids are segmented worms characterised by the clitellum or girdle which is located near the head end of mature individuals.

What kind of habitat does a clitellate live in?

Clitellates live on land, in freshwater or in the ocean. The subclass Hirudinea (leeches) contains three orders with various habitat preferences. Branchiobdellida are commensal with freshwater crayfish, grazing algae from their exoskeletons.

Is the Clitellata part of the polychaetes?

According to modern phylogenetic analyses, the Clitellata are considered to be a monophyletic clade embedded deep in the polychaetes. The group is divided into the subclasses Oligochaeta and Hirudinea. The oligochaetes contain the tubificids ( Naididae, Lumbricidae, and Lumbriculidae – commonly the tube worms and the earthworms.

What kind of mucus does the Clitellata produce?

All clitellata are hermaphrodites. During copulation, the clitellum produces a mucus that holds worms in place whilst they mate. During reproduction, the clitellum secretes a yolk (albumen) and a proteinaceous sheath which hardens.