Zigzag scallop

Zigzag scallop
Euvola ziczac
Systematics
Order : Pectinida Superfamily : Pectinoidea Family : Scallops (Pectinidae) Subfamily : Pectininae Genre : Euvola Type : Zigzag scallop
Scientific name
Euvola ziczac
( Linnaeus , 1758)

Zigzag scallops from Venezuela

The zigzag scallop ( Euvola ziczac ) is a type of shell from the scallop family (Pectinidae).

features

The clearly unevenly hinged case is up to 70 millimeters in size (up to 102 mm: Abbott & Morris). The upper left flap is flat or even slightly concave or with a central concave bulge, the right lower flap is deeply convex and overlaps the upper flap. The case is almost on the same side, the two triangular ears are about the same size. The side edges are often frayed a little irregularly. A byssus slot is not visible. The edge of the case is notched, the dorsal edge formed by the ears is almost straight to slightly concave. The umbonal angle is approx. 110 °. The rear and front edges are noticeably slightly concave.

The whitish skin is firm. The ornamentation consists of radial, smooth ribs; however, it is slightly different on the left and right flap. The ribs on the right valve are wide and low, the ribs on the left valve are denser and more flattened.

The drawing on the left flap usually consists of dark purple zigzags on a cream, orange or light purple background. The zigzags run across the radial ribs; but are often indistinct. The right flap is less intensely colored, the background is whitish or slightly yellowish, zigzags are not formed or can hardly be seen.

Similar species

The zigzag scallop is similar to the species Euvola raveneli , but has rounded, clearly separated ribs on the upper left flap. The color pattern is not as intense and consists of radial rays, not zigzags.

Geographical distribution and habitat

The distribution area extends from North Carolina and Bermuda southwards through the Caribbean , the Gulf of Mexico , northern South America to southern Brazil . A bait pot containing three specimens of Euvola ziczac was found on the coast of Dorset (southern England) .

The animals live in moderately deep water to a depth of about 100 m, half buried in coral sand. They filter the water between the free water column and the sediment surface. The main food is diatoms .

Reproduction

The animals are asynchronous hermaphrodites . Sex products are produced and sold in summer, autumn and spring. Protandric individuals dominate in spring , while proterogynous individuals predominate in summer and autumn . In contrast, populations in northern Venezuela were synchronous hermaphrodites with two breeding seasons, one in April / May and one in August / September.

commercial use

The zigzag mussel was fished commercially off the Brazilian coast beginning in 1973. In 1980, 8,800 tons were landed. After that, the stocks gradually collapsed completely. Since 1995 only a few hundred kilograms have been caught each year.

Taxonomy

The taxon was founded in 1758 by Carl von Linné in the combination Ostrea ziczac . It is the type species of the genus Euvola Dall, 1898.

supporting documents

literature

• R. Tucker Abbott, Percy A. Morris: A Field Guide to Shells: Atlantic and Gulf Coasts and the West Indies. 4th ed., 350 pp., Boston, Houghton Mifflin, 1995 ISBN 0-395-69780-8 , pp. 26/27.
• Blair Witherington, Dawn Witherington: Florida's Seashells: A Beachcomber's Guide. IV, 83 pp. Sarasota, Fla., Pineapple Press, 2007 ISBN 1-56164-387-4 , p. 50.

On-line

• Marine Bivalve Shells of the British Isles: Euvola ziczac (Linnaeus, 1758) (Gmelin, 1791) (site of the National Museum Wales, Department of Natural Sciences, Cardiff)

Individual evidence

1. ^ Theodor CH Cole: Dictionary of Invertebrates / Dictionary of Invertebrates: Latin-German-English. Berlin, Springer Spektrum, 2017 ISBN 978-3-662-52869-3 p. 53. Preview on Google Books
2. ↑ ^{a b} Paulo Ricardo Pezzuto; Carlos Alberto Borzone: The collapse of the scallop Euvola ziczac (Linnaeus, 1758) (Bivalvia: Pectinidae) fishery in Brazil: changes in distribution and relative abundance after 23 years of exploitation. Brazilian Journal of Oceanography, 52 (3-4): 225-236, 2004, doi : 10.1590 / S1679-87592004000300005
3. ^ Carl von Linné: Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Pp. 1-824, Holmia / Stockholm, Salvius, 1758. Online at www.biodiversitylibrary.org (p. 696).
4. ↑ MolluscaBase: Euvola ziczac (Linnaeus, 1758)

Web links

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