Search results
Results from the WOW.Com Content Network
However, 'earthworm' can be a source of confusion since, in most of the world, other species are more typical. For example, through much of the unirrigated temperate areas of the world, the "common earthworm" is actually Aporrectodea (=Allolobophora) trapezoides, which in those areas is a similar size and dark colour to L. terrestris.
Oligochaetes are well-segmented worms and most have a spacious body cavity (coelom) used as a hydroskeleton.They range in length from less than 0.5 mm (0.02 in) up to 2 to 3 metres (6.6 to 9.8 ft) in the 'giant' species such as the giant Gippsland earthworm (Megascolides australis) and the Mekong worm (Amynthas mekongianus).
In different earthworm families, the typhlosole appears to have multiple origins. The Lumbricidae , for example, have a typhlosole which is an infolding of all layers of the intestine wall, whereas in some other families (e.g. Megascolecidae ), it is an infolding of only the inner layer, and in many earthworms it is absent.
Some species of earthworm can even use the prehensile prostomium to grab and drag items such as grasses and leaves into their burrow. An adult earthworm develops a belt-shaped glandular swelling, called the clitellum, which covers several segments toward the front part of the animal. This is part of the reproductive system and produces egg ...
Fertilization and development of earthworm eggs takes place in the cocoon. Leeches' eggs are fertilized in the ovaries, and then transferred to the cocoon. In all clitellates the cocoon also either produces yolk when the eggs are fertilized or nutrients while they are developing. All clitellates hatch as miniature adults rather than larvae. [46]
Many animals with a wormlike cylindrical body have a hydrostatic skeleton with a flexible skin and a water-filled body cavity (coelom or pseudocoelom). They move by peristalsis, using opposed circular and longitudinal muscles, which act on the hydrostatic skeleton to change the body's shape. Hydrostatic skeletons are typically arranged in a ...
Discarded exoskeleton of dragonfly nymph Exoskeleton of cicada attached to a Tridax procumbens (colloquially known as the tridax daisy)An exoskeleton (from Greek έξω éxō "outer" [1] and σκελετός skeletós "skeleton" [2] [3]) is a skeleton that is on the exterior of an animal in the form of hardened integument, which both supports the body's shape and protects the internal organs ...
This is a featured picture, which means that members of the community have identified it as one of the finest images on the English Wikipedia, adding significantly to its accompanying article. If you have a different image of similar quality, be sure to upload it using the proper free license tag , add it to a relevant article, and nominate it .