Purpura (gastropod)
Case of purpura bufo ( top right) and two case of Purpura persica. Lovell Augustus Reeve, 1843 Conchologia Iconica
Purpura is the name of a genus of the family of whelks, which consists of two medium-sized snail -eating snail species in the Indo-Pacific. Lamarck subsumed in 1822 still exactly 50 species under this genus.
Features
The medium-sized, ovoid, slightly flattened dorsoventrally case of purpura species have a low thread and a very wide body estuary, which occupies at least two -thirds of the housing length. The sculpting is rather poorly developed, so there are numerous low longitudinal ribs, which can carry small nodules or blunt spines. The columella is wide, hollow and bears no teeth. The inside of the outer lip is longitudinally striped ( in a spiral direction). Unlike Nucella types of opening edge is not thickened and bears no teeth. The snails have an elliptical foot which is shorter than the house and does not exceed the creeping animal about this. At the top sit two pointed, conical probe, in the middle of the outside are the eyes. The operculum is horny and crescent- shaped.
Occurrence and life
The snails of the genus Purpura live in the intertidal zone in tropical waters of the Indo-Pacific. They feed primarily on snails - in particular centrifugal snails and snail beach - who attack them by pressing their proboscis under the operculum. The prey is paralyzed with a liquid from the Hypobranchialdrüse that contains choline, which relax the sphincter muscles and thus lead to opening of the operculum or the clam shell halves. This liquid turns on the air for purple dye.
History of systematics
Purpura is the Latinized form of the Greek word πορφύρα that was used with the meaning Purpurschnecke also by Aristotle for the people living in the Mediterranean species Hexaplex trunculus and Bolinus brandaris. Pliny the Elder different forming screw Purpura and Murex, Murex loud Mucianus of which is the broader way between the two purples. As a generic name in modern times purpura (French Pourpre ) 1789 by Jean -Guillaume Bruguiere is introduced in his Natural History of the worms. Jean -Baptiste de Lamarck in 1822 subsumed in his Natural History of invertebrates under the genus Purpura 50 species, as the first and the type species Purpura persica. In this large scale was the genre for a long time validity. In the mid-20th century, the genus has been split into several genera, with more names of Peter Frederick Roeding (1798 ) came from the catalog of Conch Collection of Joachim Friedrich Bolten for use, including the names of Nucella, Thais and Drupa. It was partly to confusion, because the entity specified by Röding Purpura lapillus does not match the type of the Nordic Purpurschnecke Buccinum lapillus Linnaeus - since Lamarck Purpura lapillus - matched what enticed to some authors, to give the type the name Thais lapillus. In Nucella theobroma just mentioned there of Röding but it is in fact the Nordic purple snail, so that ultimately the choice must fall on the oldest genus name Nucella.
Since then, the four Central American Snails are outsourced and the genus Plicopurpura Cossmann, form 1903, the genus Purpura limited to two types of Indopazifiks. These are Purpura persica (Linnaeus, 1758) and purpura bufo Lamarck, 1822.