Habitat Earthworms are found in many terrestrial environments ranging from semiarid habitats to moist, well-vegetated areas. Earthworms are more common in wetter areas and can be found in soil, leaf litter and under rocks and logs. Many are often found on the surface after heavy rain, moving out of the soil as it becomes waterlogged.
Entomology Home. About this Site. About invertebrates. Insects and their Allies. Leeches are also worms belonging to the same Phylum and class, but sub class Hirudinae and are of three types, freshwater, terrestrial and marine. The similarities and differences between earthworms and leeches are outlined below. Earthworms have a segmented tube-like body connected by a continuous gut, a nerve and a blood vessel. The number of segments varies in different species from 37 up to segments.
The outside body is slimy and muscular. The body of a leech is divided into 34 segments. The first 6 segments form an anterior oral sucker which is used to attach to the body of the host. A large posterior sucker is also found at the posterior end which helps in the locomotion of the animal.
From a distance, a leech can resemble a slug. Earthworms feed on organic matter found in the soil such as dead leaves. They also ingest small soil particles that are digested in the intestine. Some species of leech hematophagus feed on blood. Other species feed on decomposing bodies and open wounds of amphibians, reptiles, fish and even mammals.
Hematophagus leeches can bite, suck out blood from the host, secreting an aesthetic to an anti-clotting enzyme into the blood. As a result, leech bites bleed longer than normal wounds. Earthworms are hermaphrodites which mean that it has both male and female reproductive organs. The worms have two pairs of testes surrounded by testes sac, which produce and store sperms, ovaries and ovipores in segment 13 and some species use spermathecae or internal sacs to store sperms from other worms at the time of copulation.
Other species have spermatophores, externally located where the sperms from other worms are stored. These include a lather of bath soap smeared on exposed parts and left to dry, applications of eucalyptus oil, tropical strength insect repellent, lemon juice and impenetrable barriers of socks and pantyhose. The presence of hirudin in the wound following a leech bite may cause oozing to continue for several hours.
Although inconvenient, blood loss is not significant. Gut bacteria can cause wound infection. In the post-operative use of leeches this is closely monitored and dealt with by use of the appropriate antibiotic. There may also be a delayed irritation and itching after a bite. There appears to be no support for the theory that mouthparts left behind after forced removal of the leech causes this reaction.
There is no evidence to suggest that they do. The presence of trypanosomes in the gut of jawless leeches has been noted, but jawed leeches do not appear to be hosts. Trypanosomes cause the African sleeping sickness in humans. Leeches transmit trypanosomes that infect fish, crocodiles and even platypus, but none of them are dangerous to humans.
Allergy to leech bite has been reported. Medical opinion should be sought, depending on the severity of the reaction. Trypanosomes of Australian mammals: A review Craig K. Thompson , Stephanie S. Godfrey, R. Andrew Thompson. The Australian Museum respects and acknowledges the Gadigal people as the First Peoples and Traditional Custodians of the land and waterways on which the Museum stands.
Image credit: gadigal yilimung shield made by Uncle Charles Chicka Madden. This website uses cookies to ensure you get the best experience on our website. Learn more. Skip to main content Skip to acknowledgement of country Skip to footer This photo was taken at Somersby Falls, New South Wales, where the leeches were 'searching for blood'. This one was on a leaf and I'm sure it could smell blood as he arched and was looking for a spot to attach.
Introduction Leeches are annelids or segmented worms, and although closely related to the earthworms, are anatomically and behaviourally more specialised. Identification Leeches are segmented worms in the Subclass Hirudinea that are usually ectoparasitic.
Habitat Most leeches are freshwater animals, but many terrestrial and marine species occur. Distribution There are around species of leeches world wide. These are divided into two major infraclasses Euhirudinea: the 'true' leeches — marine, freshwater and terrestrial — which have suckers at both ends and lack chaetae bristles Acanthobdellida: a small northern hemisphere infraclass ectoparasitic on salmoniid fish, which lack an anterior sucker and retain chaetae.
The Euhirudinea is further divided into two orders: Rhynchobdellida: jawless marine and freshwater leeches with a protrusible proboscis and true vascular system Arynchobdellida: jawed and jawless freshwater and terrestrial leeches with a non-protrusible muscular pharynx and a haemo-coelomic system.
Feeding and diet Most leeches are sanguivorous, that is they feed as blood sucking parasites on preferred hosts. Leeches are grouped according to the different ways they feed: One group the jawed leeches or Gnatbobdellida have jaws armed with teeth with which they bite the host. You can read lots more about leeches in the two factsheets below:. Tropical gardeners know flatworms as the colourful but slimy worms that are found under rotting wood or vegetation in the compost bin. They have a coating of mucous to prevent their bodies from drying out.
This mucous layer also helps their movement as they put down the slimy layer and use tiny cilia feet to slide forward over it. Flatworms are carnivorous and feed on slugs and earthworms. They are hermaphroditic have both male and female organs in the one body and some species can also 'duplicate' themselves if they are split in half!
A well known flatworm of school days is the planaria - a little flatworm with a shovel-shaped head. A school experiment of long ago was the old 'two headed trick': if this worm were to be cut through the middle of its head, it would regenerate each of the missing halves and therefore, end up with two heads! There are thousands of nematode species but the vast majority are either microscopic or only 1mm long. Not all are parasitic but those that are make quite an impression on us, our pets, wildlife and even the agricultural industry.
Some nematodes are actually used to control other pests and research is progressing in this area. Toggle navigation. Property information form How you can help!
Crabs, crayfish, leeches, land snails, worms, centipedes, millipedes
0コメント