How many species of Oligochaeta are there?

How many species of Oligochaeta are there?

oligochaete, any worm of the subclass Oligochaeta (class Clitellata, phylum Annelida). About 3,500 living species are known, the most familiar of which is the earthworm (q.v.), Lumbricus terrestris. Oligochaetes are common all over the world. They live in the sea, in fresh water, and in moist soil.

Are oligochaetes asexual?

Oligochaetes are hermaphroditic which means they have the sexual parts of both the male and female.

Are oligochaetes Marine?

Distribution and habitat Oligochaetes occur in every continent in the world occupying terrestrial, freshwater and marine habitats. Of the 1700 known aquatic species, about 600 are marine and 100 inhabit groundwater.

What class is Oligochaeta?

ClitellataEarthworms / Class

What does the name Oligochaeta mean?

(ˈɑlɪgoʊˌkit ) noun. any of a class (Oligochaeta) of annelid worms, as the earthworm, lacking a definite head and having relatively few body bristles: found chiefly in moist soil and fresh water. Derived forms.

Do Blackworms have eyes?

Worms that hold their tail up to the water surface may quickly withdraw it if a shadow suddenly occurs. This is because these worms have tiny simple eyes (called photoreceptor cells) scattered along their tail segments!

How many species of polychaetes are there?

polychaete, any worm of the class Polychaeta (phylum Annelida). About 8,000 living species are known.

How do polychaetes differ from earthworms?

Earthworms differ from polychaetes in that they do not have parapodia but DO possess a clitellum, which is used in reproduction. Though most live in the upper layers of the soil there are freshwater species within this group.

Is Clitellata a class?

The Clitellata are a class of annelid worms, characterized by having a clitellum – the ‘collar’ that forms a reproductive cocoon during part of their life cycles. The clitellates comprise around 8,000 species.

What is unique about a Oligochaeta?

Thus, unlike polychaetes, oligochaetes are hermaphroditic worms with internal fertilisation and complex reproductive organs which enable them to lay their eggs in protective cocoons.

How do you pronounce Pheretima?

Pheretima Pronunciation. Pher·e·ti·ma.

What are the chief characters of polychaetes?

Polychaetes usually have a well-developed head, often complete with well-developed eyes, antennae, and sensory palps. They lack any permanent sex organs (in contrast to other kinds of annelids); gonads appear as swellings during the breeding season.

How do you identify polychaetes?

The polychaetes are segmented worms (Phylum Annelida), as are earthworms (Oligochaeta). The polychaetes can be distinguished by having paired, lateral appendages, parapodia, on each segment. The parapodia are usually divided into dorsal notopodia and ventral neuropodia.

What are the major characteristics of polychaetes?

Why are polychaetes different?

Polychaetes differ from other annelids in having a well differentiated head with specialized sense organs and no clitellum. They have many setae, usually arranged in bundles on the parapodia. The head bears eyes, antennae, and sensory palps.

What is the difference between leeches and polychaetes?

Polychaetes are the most diverse group of annelids and most live in the marine environment. They differ from earthworms and leeches in that they have appendages called parapodia and do not possess a clitellum.

What is a Lumbriculidae?

The Lumbriculidae are a family of microdrile oligochaetes common in freshwater environments, including streams, lakes, marshes, wells and groundwater. They should not be confused with the earthworm family Lumbricidae.

What is the only family in the Order Lumbriculida?

Lumbriculidae are the only family in the order Lumbriculida. ^ B. G. M. Jamieson (1988). “On the phylogeny and higher classification of the Oligochaeta”.

Are earthworms and lumbriculids the same thing?

They should not be confused with the earthworm family Lumbricidae. Many species and genera are highly endemic, mainly in Siberia and the western parts of North America. Lumbriculidae are the only family in the order Lumbriculida.

What is the difference between Lumbriculus codensis and Thinodrilus lineatus?

^ Note that Lumbriculus lineatus and Lumbriculus codensis, which are sometime seen, both belong to the enchytraeid genus Lumbricillus. The old genus Thinodrilus is now considered to be a part of Lumbriculus, but may have subgeneric status.