The Subphylum Crustacea

The Subphylum Crustacea - important(yum yum Krill and a few...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
The Subphylum Crustacea The Subphylum Crustacea, shown in Figure 19, contains 30,000 mostly marine species. A few species live in freshwater. Lobsters, crabs, crayfish, shrimp, copepods, barnacles, and several other groups of organisms belong to this subphylum. All crustaceans possess two pairs of antennae, a pair of mandibles, a pair of compound eyes (usually on stalks), and two pair of maxillae on their heads, followed by a pair of appendages on each body segment. Crustaceanbodies usually have a head, thorax, and abdomen. Crustaceans utilize gills for gas exchange. .
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Most crustaceans are free-living, but some are sessile and a few are even parasitic . Some crustaceans filter tiny plankton or bacteria from the water, while others are active predators. A few crustaceans scavenge nutrients from detritus. Many species, including lobsters, crayfish, barnacles, and crabs are economically
Background image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: important (yum, yum). Krill, and a few other species, form the base of extremely important marine food chains . Still others are crucial in recycling nutrients trapped in the bodies of dead organisms. The subphylum contains several taxonomic classes. We will focus on one, the class Malacostraca, which includes the shrimp, lobsters, etc. The Subphylum Uniramia This subphylum contains arthropods that have unbranched appendages. The uniramian body has two or three tagmata, and an abdomen that has many segments. Appendages in the head region include paired antennae and mandibles, and also two pairs of maxillae. Gas exchange is by means of tracheae and spiracles. This subphylum include millipedes, centipedes, and insects....
View Full Document

This note was uploaded on 11/29/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.

Page1 / 3

The Subphylum Crustacea - important(yum yum Krill and a few...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online