How many phyla in animalia

Snail mucus is used in "snail cream" cosmetics. The cream is used to treat damaged skin and as a skin moisturizer. The formidable bloodworm Glycera , a predaceous intertidal worm phylum Annelida with four fanglike jaws at the anterior end red arrow.

The hollow fangs inject poison from venom glands into its prey. The elongate body is composed of many segments, each segment with fine bristlelike setae for locomotion.

This interesting worm lives in tubular gallaries constructed in muddy bottoms. Lying in wait within its tube, the worm can detect the surface movements of prey by changes in the water pressure. It slowly moves to the opening of its burrow and then seizes the prey, such as small crustaceans and other invertebrates, with its proboscis. The proboscis can be extended to about one fifth the length of its body. When retracted, the proboscis occupies approximately the first 20 body segments.

During the capture of prey, the proboscis is everted with explosive force, and the four venom fangs emerge at the tip. Peanut worms phylum Sipunculoidea are named after their shape when when fully contracted, such as when they are handled. These interesting worms live in burrows under rocks of the intertidal zone. They are sometimes very abundant in tunnels they bore in coralline rocks, reportedly up to per square meter in some Hawaiian reefs.

The slender anterior end has a mouth surrounded by hollow tentacles. Phylum Arthropoda Arthropods. These microscopic objects are not eggs. They are the dead, chitinous, bivalve carapaces of minute crustaceans called mussel or seed shrimps. When they were alive, a tiny shrimplike animal occupied each white case. They belong to the order Ostracoda which is considered a class in some textbooks.

Another order of minute crustaceans Conchostraca are called clam shrimp; however, the bivalve carapace of an ostracod is more strikingly similar to a clam shell. Photo was taken along the shore of a desiccated vernal pool in the Santa Rosa Plateau of Riverside County, California. A thriving population of brine shrimp Artemia monica in Mono Lake, California.

These minute crustaceans belong to the order Anostraca, along with the endangered fairy shrimp Branchinecta. During the summer months, the shoreline of Mono Lake is colored pinkish-red by massive colonies of brine shrimp. The Phalarope right is swimming in circles as it feeds on the brine shrimp. A common southern California centipede Scolopendra polymorpha.

The name centipede is derived from the Latin words "centi" and "pede" foot. Centipedes belong to the class Chilopoda in the phylum Arthropoda. Adult centipedes in North America may have fewer or more than legs, one pair per body segment. Centipedes are the only animals with legs modified into fanglike "poison jaws" toxicognaths that inject poison for subduing and killing prey.

Modified forelegs, called prehensors, are located under the head. Glands inside the prehensors release venom into ducts that lead into the fangs. The last pair of legs are longer than the others.

Some species use these to subdue prey or as defensive pincers. The posterior body segment with its unique pair of legs superficially resembles the head. This "pseudohead" found in some species may serve to confuse potential predators by misdirecting their attacks to a less vital part of their body, thus leaving the head free to bite the attacker. A common question that students ask is "can centipedes bite? Magnified view of the underside of a centipede Scolopendra polymorpha showing a pair of fanglike "poison jaws" or toxicognaths red arrow.

These are actually modified forelegs that inject venom. A large southern California millipede probably Hiltonius pulchrus , a member of the class Diplopoda in the phylum Arthropoda. Diplopoda means "double-footed," and refers to two pairs of legs on each body segment. The name millipede is derived from the Latin words "milli" and "pede" foot. Actually, adult centipedes in North America may have up to legs, typically two pairs per body segment. Unlike centipedes, most millipedes are harmless detritis feeders detritivores and feed on rotting vegetation.

The horseshoe crab Limulus polyphemus lives in shallow water along the Atlantic coast and the Gulf of Mexico. It belongs to the class Merostomata in the subphylum Chelicerata. The horseshoe crab is a living representative of the subclass Xiphosura, an line of aquatic chelicerates that dates back to ancient Cambrian seas million years ago. The subphylum chelicerata is characterized by arthropods with a cephalothorax, no antennae and jaws called chelicerae. In addition to the horseshoe crab, this subphylum includes the large class Arachnida spiders, scorpions, ticks and mites.

Another large subphylum, the Mandibulata, is characterized by a head, thorax and abdomen, paired antennae and jaws called mandibles.

It includes the class Crustacea lobsters, crabs and barnacles , class Insecta insects , class Chilopoda centipedes and class Diplopoda millipedes. A sun spider or solpugid order Solpugida , an interesting member of the subphylum Chelicerata in the class Arachnida. Unlike true spiders order Araneae , the solpugid has two pairs of formidable, scissorlike jaws called chelicerae red arrow.

The jaws are arranged vertically rather than the single pair of horizontal jaws in most spiders. The elongate pair of anterior appendages are pedipalps, each tipped with a suckers that are used for capturing prey and climbing smooth surfaces. Solpugids are extremely voracious carnivores, even attacking and killing other large, webless spiders, such as wolf spiders. With their twin pairs of huge, powerful jaws, solpugids literally crush and tear their prey to shreds.

Close-up view of the anterior end of a tarantula Aphonopelma showing two sharp, fangs red arrow extending from the jaws or chelicerae.

This spider is a male because its pedipalps are tipped with a sharp-pointed, bulblike copulatory organ purple arrow. During mating the male inserts sperm into an opening on the underside of the female using the pointed copulatory organs on his pedipalps.

Several closely-spaced, orange eyes can be seen on the front of the head cephalothorax. The tarantula kills its prey by crushing and injecting them with poison through its hollow fangs. Although it is a large spider, the tarantula is hunted and killed by a large black wasp with bright red wings known as the tarantula hawk Peplis.

Close-up view of several arrow worms phylum Chaetognatha. The best known animal phyla are the Mollusca , Porifera , Cnidaria , Platyhelminthes , Nematoda , Annelida , Arthropoda , Echinodermata , and Chordata , the phylum humans belong to.

Although there are approximately 35 phyla, these nine include the majority of the species. Many phyla are exclusively marine, and only one phylum is entirely absent from the world's oceans : the Onychophora or velvet worms.

The most recently discovered phylum is Cycliophora [3] found in ; only three phyla were discovered in the last century. The Cambrian explosion was a great flowering of life forms that occurred between roughly and million years ago; during this time all modern phyla and many now-extinct ones were established.

For instance, during the Cambrian, the dominant megafauna , or large animals, were arthropods whereas now they are vertebrates chordata. Scientific classification describes the following levels of organization taxons for classifying life forms: Kingdom , Phylum, Class , Order , Family , Genus , Species , Subspecies.

Thus Phylum is a rather broad classification. Also, the Three Domain System is now widely used and adds the level of Domain above Kingdom as the broadest classification. Etymology :. Paleontology Wiki Explore. Wiki Content. Explore Wikis Community Central.

Register Don't have an account? Phylum biology. View source. History Talk 0. For the linguistic term, see Phylum linguistics.

For the plant, see Phyla genus. On the Origin of Phyla. Chicago: University Of Chicago Press, 7. In the blink of an eye: How vision kick-started the big bang of evolution. Sydney: Free Press, Basal animals: sponges, corals, and jellyfish 5. The bilaterians: building a body 6.

Lophotrochozoa: wondrous worms 7. Ecdysozoa: insects and nematodes 8. Deuterostomes I: starfish, sea squirts, and amphioxus 9.

Deuterostomes II: the rise of vertebrates Deuterostomes III: vertebrates on land Enigmatic animals End Matter Further reading Index. Show Summary Details Acknowledgements List of illustrations 1.

Enigmatic animals Further reading Index. Animal phyla p. Animal phyla. Acknowledgements List of illustrations 1. All rights reserved.