Urosalpinx cinerea

Urosalpinx cinerea

Urosalpinx cinerea is a snail from the family of whelks ( Muricidae ) that feeds primarily on shellfish, including oysters, and barnacles. From its native range, the Atlantic coast of New England, she has been abducted with the oysters among other things to the North Sea. Like some other snails with similar eating habits it is called oyster drills.

Features

The yellowish-gray shell of Urosalpinx cinerea, reaching in adult worm no more than 2.5 cm in length is, as with all Urosalpinx types of elongated oval, longitudinally ribbed and striated in a spiral direction without varices and has an oval case mouth, which in a only short, open Siphonalkanal runs out and the outer lip is perforated. The house of this type has a massive thread with bold, beaded wrinkles on his turns. The half- heart-shaped, yellow-brown to orange-colored operculum is horny with a lateral, located slightly below the center nucleus. The very small foot has a yellow border and speckled gray on the upper side. The small head reaches the active animal shows little, so that the black eyes on the sensor base is just visible, and Sipho goes just over the outcome of the Siphonalkanals.

Dissemination

The original area of ​​distribution of Urosalpinx cinerea is the Atlantic coast of North America between Nova Scotia and Florida. By importing North American oysters spawn in the context of the spread of commercial oyster farming the snail has been introduced into the North Sea and on the Pacific coast of North America between California and Washington.

Habitat

Urosalpinx cinerea lives in the intertidal zone and below on rocks and oyster reefs up to 15 m depth.

Life cycle

Like other whelks is Urosalpinx cinerea dioecious. The male mated the female with his penis. In the period from April to June secured the female over a period of about 7 days its egg masses of solid substrate, rocks, may be concrete blocks, cans or case of molluscs, for example. An egg capsule contains an average of about 9 eggs, of which develop on average about 5. The development of the veliger to metamorphosis to the finished worm runs completely in the egg capsules. Measured times of oviposition until hatching of the young animals from the capsules in water temperatures from 13.5 to 32 ° C were 18 up to 56 days. Newly hatched screw housing have lengths of about 1 to 3 mm. In Noank (Connecticut ) observed pups eat first bryozoans, especially Cryptosula palla sina, and only later go on to barnacles of the species Balanus balanoides to eat, which are the main prey of the screw in the area. In the first months the snails grow about 2.5 mm per month. Females are slightly larger than males. At the age of one year, the housing in the UK measured males are approximately 1 to 1.8 cm, the females about 2 inches tall, with two years of snails there are 1.8 to 2.3 and 2.5 cm, with ten-year 3, 6 and 3.9 cm. The snails are about 10 years, sometimes 13 to 14 years old. Sexual maturity is reached at age 1-3 years and a body length of 1.3 to 2.4 cm.

Food

Urosalpinx cinerea eats mainly mussels and barnacles, to a lesser extent snails, small crabs, bryozoans and carrion. In the shell of the prey, a hole is drilled and then guided the proboscis of the screw through the hole on the meat with the radula when exposed to acids. In feeding experiments with four preferred prey species the snails ( Crassostrea virginica ) and then barnacles ( Balanus sp.) Grew fastest when they ate clams ( Mya arenaria ), followed by a diet of American oysters. The slowest snail that grew in diet with the mussel Mytilus edulis. In Noank are in the intertidal barnacles of the species Balanus balanoides the main prey, but are in deeper areas where there are fewer barnacles, especially Great beach snails ( Littorina littorea ) eaten, sometimes a beach worm is attacked by several whelks simultaneously.

Relevance to humans

As a major predator of oysters Urosalpinx cinerea is feared in the commercial oyster farming. By this it is with oysters spawn of the North American Atlantic coast in the North Sea ( Thames Estuary in England, the Netherlands) was introduced. Like other whelks but also Urosalpinx cinerea is affected by the water pollution by tributyltin, which leads the worms imposex.