albumin:
A fluid filled with water-soluble proteins.
A period of inactivity, or dormancy, induced by unfavorable conditions. During aestivation, the earthworm curls up into a knot and becomes quite pink.
A habitat classification term. These earthworms live in deep vertical burrows, but feed at or near the soil surface, especially at night.
An organism that has a segmented body, giving it a ringed appearance. The segments are arranged one beside each other symmetrically along the length of the earthworm to form the body.
See periproct
Something that is made of or contains calcium carbonate; in soil, can occur as chalk or limestone.
Earthworm feces; the voided earth and other waste materials that are deposited on the surface of the ground. Not all species form their casts above ground.
See muscles
(see figure 1) A swelling in the skin near the head that secretes material to form cocoons. The clitellum forms a band that can be flared, non-flared, saddle shaped, or annular. The clitellum is generally found between segments 26-33.
A sac that contains the earthworm’s eggs. The cocoon is formed at the clitellum, and then travels from the clitellum to the head. Here it slides off the earthworm’s body and is deposited into the soil.
A widened portion of the digestive system that lacks the muscularity of the gizzard. It is located after the esophagus, but before the gizzard. An area where food is digested.
The small holes located in the intersegmental furrows down the middle of the earthworm’s back. These holes lead to the coelomic cavity. The term first dorsal pore 5/6 means that this is the first dorsal pore and it is located between segments 5 and 6.
A habitat classification term. These earthworms burrow continuously to form a network of channels – some vertical and some horizontal in the rhizosphere. The majority of the burrows are horizontal.
A habitat classification term. These earthworms are not strong burrowers, and live in the uppermost layers of the soil or litter layer (i.e. decaying plant debris, or compost). They can form some shallow vertical burrows where they temporarily escape from drought, heat, and disturbances.
See prostomium.
See clitellum.
Glandular swellings, pits or grooves of the epidermis (skin). See genital tumescences.
(see figure 1) Areas of modified epidermis without distinct boundaries, through which follicles of genital setae open.
The muscular portion of the digestive system where food is digested. It is located immediately after the crop, and just before the intestine.
The amount of time required for a known amount (volume or weight) of water to soak through the soil.
The area between two consecutive segments. It is here where the skin is thinnest and where, in pigmented species, color is lacking.
Shimmering colours on the surface of the earthworm’s skin as a result of refracted light. Green and blue are common iridescent colours.
Those earthworms without genital markings such as the clitellum, tubercula pubertatis, or genital tumescence. This stage of the life cycle is located between the hatchling phase and the appearance of genital markings (adult stage).
See muscles
Earthworms travel by coordinating two kinds of muscles: circular and longitudinal muscles. Both are located under the epidermis. When the circular muscles contract, the segments become thinner (decrease in segment diameter), the earthworm lengthens and moves forward. When the longitudinal muscles contract, the segments become thicker (increase in segment diameter), and the earthworm shortens.
One of the taxonomic classes in the phylum Annelida. Members of this class have segmented bodies, setae on all segments (except the peristomium and periproct), a true coelom, a closed vascular system, and crawl using circular and longitudinal muscles.
(see figure 1) The last segment of the earthworm’s body; contains the anus.
(see figure1) The first segment of the earthworm’s body; contains the mouth.
An indication of soil acidity or alkalinity, which is expressed on a pH scale (0-14). A pH less then 7 is acidic, 7 is neutral, and greater then 7 is alkaline.
The occurrence of slightly different looking individuals within the same species; slight variations within one species.
Earthworms who have passed their reproductive period. They no longer have a clitellum, but do show a discolouration where the clitellum and genital markings were once located.
(see figure 1) The lobe of skin that projects out in front of the first body segment (peristomium). It is located above the mouth, and there are three formations as seen in dorsal view.
The area immediately around plant roots, including the roots itself. This is an area of intense microbial activity, where plants, microorganisms, other soil organisms, and soil structure and chemistry, interact in complex ways.
The small furrows (wrinkles) that occur in-between the intersegmental furrows.
The small rings that surround the length of the earthworm’s body. They are simply folds in the skin.
(see figure 1) The bristles (or hairs) that are found on an earthworm’s body. They help the earthworm to move and act to sense the environment.
(see figure 1) The arrangement of the setae on the earthworm’s body. Three arrangements exist: closely paired, widely paired, and separate.
(see figure 1) Glandular swellings that occur on both sides of the clitellum. They are not always present, and they can be continuous or discontinuous with the clitellum. Their size and shape may vary from long narrow bands, triangles, or sucker-like shapes, depending on the species.