Earthworm belongs to which family

Hence, they are the most advanced worms. A well-developed and complete digestive system is present in earthworms oligochaetes with a mouth, muscular pharynx, esophagus, crop, and gizzard being present. The gizzard leads to the intestine and ends in an anal opening. A cross-sectional view of a body segment of an earthworm a terrestrial type of annelid is shown in Figure 2; each segment is limited by a membranous septum that divides the coelomic cavity into a series of compartments. Figure 2.

This schematic drawing shows the basic anatomy of annelids in a cross-sectional view. Annelids possess a closed circulatory system of dorsal and ventral blood vessels that run parallel to the alimentary canal as well as capillaries that service individual tissues.

In addition, these vessels are connected by transverse loops in every segment. These animals lack a well-developed respiratory system, and gas exchange occurs across the moist body surface.

Annelids show well-developed nervous systems with a nerve ring of fused ganglia present around the pharynx. The nerve cord is ventral in position and bears enlarged nodes or ganglia in each segment.

Annelids may be either monoecious with permanent gonads as in earthworms and leeches or dioecious with temporary or seasonal gonads that develop as in polychaetes. However, cross-fertilization is preferred in hermaphroditic animals. These animals may also show simultaneous hermaphroditism and participate in simultaneous sperm exchange when they are aligned for copulation.

Phylum Annelida contains the class Polychaeta the polychaetes and the class Oligochaeta the earthworms, leeches and their relatives. The many chetae of polychaetes are also arranged within fleshy, flat, paired appendages that protrude from each segment called parapodia , which may be specialized for different functions in the polychates. The subclass Hirudinea includes leeches such as Hirudo medicinalis and Hemiclepsis marginata.

The class Oligochaeta includes the subclass Hirudinia and the subclass Brachiobdella. A significant difference between leeches and other annelids is the development of suckers at the anterior and posterior ends and a lack of chaetae.

Additionally, the segmentation of the body wall may not correspond to the internal segmentation of the coelomic cavity.

This adaptation possibly helps the leeches to elongate when they ingest copious quantities of blood from host vertebrates.

The subclass Brachiobdella includes species like Branchiobdella balcanica sketi and Branchiobdella astaci , worms that show similarity with leeches as well as oligochaetes. Figure 3. The a earthworm, b leech, and c featherduster are all annelids. Phylum Annelida includes vermiform, segmented animals. Segmentation is seen in internal anatomy as well, which is called metamerism.

Annelids are protostomes. These animals have well-developed neuronal and digestive systems. Some species bear a specialized band of segments known as a clitellum.

There are 16 different families to which a given earthworm may belong. The earthworm genus is generally accepted to be Lumbricus.

There are approximately 4, different species of earthworm. You should be able to find out more about a particular earthworm's taxonomy by narrowing it down based on region and habitat. Local field guides and biological texts are an invaluable resource to finding the exact taxonomy of a given earthworm.

Goody Clairenstein has been a writer since She has sat on the editorial board of several non-academic journals and writes about creative writing, editing and languages. She has worked in professional publishing and news reporting in print and broadcast journalism.

Her poems have appeared in "Small Craft Warnings. How Do Earthworms Move? How Do Earthworms Protect Themselves? The Anatomy of the Hydra. Worms in the Ecosystem. Cephalization of Earthworms. What Does a Roundworm Look Like?