Pterotracheidae

Pelagic worm Pterotracheidae the family. Links of the trunk, above the Flipper, right of the visceral core

The Pterotracheidae are a family of snails, which are adapted to a pelagic lifestyle. They somewhat resemble the planktonic arrow worms.

Features

The body is soft, gelatinous transparent and elongated. The front is a movable snout, and the eyes, the foot is transformed into a Flipper, the organs located in the back in a small, visceral core area referred. There are also the gonads and gills. The opaque visceral core is camouflaged by phosporeszierendes light. The housing is completely degenerated. The animals float on your back with the help of the back and fins herschlagenden foot.

Nutrition

The Pterotracheidae feed on prey on small fish, salps, jellyfish, arrow worms, and other planktonic molluscs. They themselves are eaten by fish and sea turtles.

Occurrence

Their habitat are the warm seas around the world, including the Mediterranean, where they inhabit the upper 200 meters of the water column in large flocks.

System

Two genera are provided to the family:

• Pterotrachea Forskål, 1775
• Firoloida Lesueur, 1817

Previously also other genera ( eg Carinaria ) were asked to the family often, but these are now placed in their own families within the superfamily Pterotracheoidea.