Megascolecidae
From Wikipedia, the free encyclopedia
 |
||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Scientific classification | ||||||||||||
|
||||||||||||
|
|
||||||||||||
|
See text. |
Megascolecidae is a large family of earthworms which has native representatives in Australia, New Zealand, Southeast and East Asia, and North America. Membership requires a 'megascolecine' arrangement of male pores, rather than an 'acanthodriline' arrangement found in Acanthodrilidae, Octochaetidae and Exxidae. Primitive members of the family show a Gondwanan distribution and have been used as evidence of continental drift. Members of the Pheretima group of genera (e.g. Amynthas) are widely distributed around the tropics, much as some Lumbricidae are distributed through the temperate zones. The North American native genera Argilophilus, Driloleirus, Arctiostrotus and others belong to this family.
Many genera in the Megascolecidae are meroic where the nephridia, instead of having the primitive holoic arrangement of two per segment, have become broken up into many. Some taxa also exhibit enteronephry where the nephridia, instead of emptying to the body surface, empty into the digestive tract.
