Phyllocarida

Nebalia bipes

The Phyllocarida ( German also Phyllocariden ) are a group of small marine crustaceans. They form a subclass of the higher crustaceans ( Malacostraca ) and contain only a recent order, the Leptostraca.

Description

Phyllocariden have a bivalved carapace, whose two halves are fused together at the back ( dorsomedial ). This laterally flattened shield covers the head, the thorax and part of abdomen ( tummy). The front of the Carapy consists of a movable rostrum. The eyes are stalked and provided with only a few light-sensitive elements (the kind Dahl Ella is as blind).

The crustaceans in this group have not differentiated, leaf -shaped pereiopods, six pairs of pleopods ( swimming legs ) and no maxillipeds or uropods about eight pairs. Instead of this they have a fork-shaped furca.

Occurrence and life

Phyllocarida are found in all oceans, although some species are more widespread. So Nebalia and Nebaliopsis are cosmopolitans, while about Dahl Ella found only in submarine hydrothermal vents of the Galapagos Islands, and Speonebalia only in sea caves in the Turks and Caicos.

With the exception of the pelagic species Nebaliopsis Phyllocariden benthic organisms that prefer muddy bottoms are a low oxygen content. They live both in the intertidal and in the abyssal sea zone. A filtered nutrition, it is believed, but they are also found in carrion.

System

• Subclass Phyllocarida Packard, 1879

• † order Archaeostraca
• † order Hoplostraca
• † order Canadaspidida
• Order Leptostraca Claus, 1880