''Pontoscolex'' is a genus of earthworms in the family

Glossoscolecidae The Glossoscolecidae are a large family of earthworms (annelids) which has native representatives in South and Central America. The species '' Pontoscolex corethrurus'' has a circumtropical distribution. They are found mostly in forest, but one ...

, or alternatively, in the family Rhinodrilidae.

General characteristics

The type species '' Pontoscolex corethrurus'' has a circumtropical distribution, although it originates in the

Neotropics The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...

, probably in the Guiana Plateau. It reproduces

parthenogenetically Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development ...

, and under experimental conditions can complete its life cycle in about one year. Adults measure in length.

Diagnostic characteristics

There are eight

seta In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. Th ...

e per segment, arranged in regular rows, at least in the anterior part of the animal, whereas in the posterior part the arrangement varies (regular, more or less irregular, or in

quincunx A quincunx () is a geometric pattern consisting of five points arranged in a cross, with four of them forming a square or rectangle and a fifth at its center. The same pattern has other names, including "in saltire" or "in cross" in heraldry (dep ...

). No pigment is usually present. Male pores and tubercula pubertatis are in the clitellar region. The

gizzard The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ found in the digestive tract of some animals, including archosaurs (pterosaurs, crocodiles, alligators, dinosaurs, birds), earthworms, some gastropods, so ...

is in the segment VI. Three pairs of calciferous glands of tubular-dichotomous (panicled) structure are in the segments VII–IX. Dorsal, ventral, supra- and subesophageal and subneural vessels are present. Lateral hearts are located in the segments VII–IX and intestinal hearts in the segments X and XI. The holonephridia have terminal

sphincter A sphincter is a circular muscle that normally maintains constriction of a natural body passage or orifice and which relaxes as required by normal physiological functioning. Sphincters are found in many animals. There are over 60 types in the hum ...

. They are metandric and metagynous. The

seminal vesicle The seminal vesicles (also called vesicular glands, or seminal glands) are a pair of two convoluted tubular glands that lie behind the urinary bladder of some male mammals. They secrete fluid that partly composes the semen. The vesicles are 5� ...

s are usually long and band-like, piercing a number of

septa The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people in five coun ...

Spermatheca The spermatheca (pronounced plural: spermathecae ), also called receptaculum seminis (plural: receptacula seminis), is an organ of the female reproductive tract in insects, e.g. ants, bees, some molluscs, oligochaeta worms and certain other ...

e are simple.

Species

* '' Pontoscolex corethrurus'' (Müller, 1856) * '' Pontoscolex cuasi'' (Righi, 1984) * '' Pontoscolex cynthiae'' (Borges & Moreno, 1990) * '' Pontoscolex franzi'' (Zicsi & Csuzdi, 1999) * '' Pontoscolex hingstoni'' (Stephenson, 1931) * ''

Pontoscolex hystrix ''Pontoscolex'' is a genus of earthworms in the family Glossoscolecidae, or alternatively, in the family Rhinodrilidae. General characteristics The type species '' Pontoscolex corethrurus'' has a circumtropical distribution, although it origi ...

'' (Perrier, 1872) * ''

Pontoscolex kuneguara ''Pontoscolex'' is a genus of earthworms in the family Glossoscolecidae, or alternatively, in the family Rhinodrilidae. General characteristics The type species '' Pontoscolex corethrurus'' has a circumtropical distribution, although it origi ...

'' (Righi, 1989) * ''

Pontoscolex lilljeborgi ''Pontoscolex'' is a genus of earthworms in the family Glossoscolecidae, or alternatively, in the family Rhinodrilidae. General characteristics The type species '' Pontoscolex corethrurus'' has a circumtropical distribution, although it origi ...

'' (Eisen, 1896) * '' Pontoscolex maracaensis'' (Righi, 1984) * '' Pontoscolex melissae'' (Borges & Moreno, 1990) * '' Pontoscolex nogueirai'' (Righi, 1984) * '' Pontoscolex pydanieli'' (Righi, 1988) * '' Pontoscolex spiralis'' (Borges & Moreno, 1990) * '' Pontoscolex vairemensis'' (Righi, 1985) * '' Pontoscolex vandersleeni'' (Michaelsen, 1933)

References

{{Taxonbar, from=Q18519120 Haplotaxida Annelid genera