Catworm

Nephtys incisa

Has a cylindrical, elongated body with 60 to 70 segments and bristles down the sides of the body. It has a defined head that is bowl-shaped or round and a prominent proboscis (extensible tubular sucking organ). Individuals are brown or cream-colored. Adults range in length from 2.5 centimetres to 6.5 centimetres. They grow approximately 12 to 20 millimetres in length per year.

Authority

Malmgren, 1865

Classification Details

Phylum: Annelida (worms); Class: Polychaeta (bristle worms)

Habitat

In the northwest Atlantic found from Baffin Island to Virginia. Also occurs on European and South American coasts. The adult is benthic, and the larval stage is planktonic. The adult lives in sediment ranging from mud to soft silt. It is found in both shallow and deep water. Disturbances of the marine floor and pollution both negatively impact its numbers.

Diet

Using its proboscis (an extendable tubular sucking organ), it eats the mud it burrows through. Food includes detritus and diatoms. It is not selective of the food that it eats.

Reproduction

Sexes are separate. Adults reproduce throughout the year, with peaks in spring and fall. The first larval stage is the trochophore (which is a free-swimming zooplankton), in which segments begin to appear. The later larval stages more closely resemble adults.

Fun Facts

The word polychaete means "many hairs," in reference to its many bristles.

This species is sensitive to pollution and can be used as an indicator species.

References

Clark RB (1962) Observations on the Food of Nephtys. Limnology and Oceanography 7, 380–385.

Mayhew EM (2005) Nephtys incisa A catworm. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. Available from: https://www.marlin.ac.uk/species/detail/1821 Accessed online 22 January 2020.

Pocklington P (1989) Polychaetes of Eastern Canada – An Illustrated Key to Polychaets of Eastern Canada Including the Eastern Arctic. Mont Joli: Department of Fisheries and Oceans.

Read G and Fauchald K (2020) World Polychaeta database. Nephtys incisa Malmgren, 1865. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=130362 Accessed online 22 January 2020.

Van Guelpen L, Pohle G, Vanden Berghe E and Costello MJ (2005) Marine Species Registers for the North Atlantic Ocean. World Wide Web electronic publication. http://www.vliz.be/vmdcdata/narms/

Zajac RN and Whitlatch RB (1988) Population ecology of the polychaete Nephtys incisa in Long Island sound and the effects of disturbance. Estuaries 11, 117–133.