Pheretima
Encyclopedia
Pheretima is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...

s found mostly in New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...

 and parts of Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

.

The clitellum
Clitellum
The clitellum is a thickened glandular section of the body wall in earthworms and leeches, that secretes a viscid sac in which the eggs are deposited...

 is a band of grandular tissue present on segments 14 to 16. Individuals are hermaphroditic and reproduction can be either sexual or parthenogenetic. Female genital pores lie on the ventral surface of segment 14. A pair of male gential pores is situated ventrally on segment 18. Genital papiliae may also be present ventrally. As with all earthworms, development of young is without a larval stage and takes place in cocoons.

Similar genera include Amynthas
Amynthas
Amynthas is a genus of earthworms in the family Megascolecidae.-Species:* Amynthas alexandri * Amynthas borealis Panha & Bantaowong, 2011* Amynthas comptus * Amynthas defecta...

, Archipheretima, Duplodicodrilus, Metaphire, Metapheretima, Pithemera, and Polypheretima. In combination these "pheretimoid" genera have about 1,000 species making them an important ecological and taxonomic group of Oriental species (cf. Lumbricidae from Eurasia; Moniligastridae from Indo-Asian region).
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK