Annelids

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Annelids - Segmented Worms

General Information

Latin: Annulus = Little Ring
Also known as ringed worms or segmented worms
Includes earthworms, leeches, marine worms
Approximately 15,000 + species, ranging in size from microscopic (less than 1mm) to the Australian giant Gippsland earthworm (3m long)
2/3 of annelids are marine species

Distribution

Found worldwide

Habitat

Live in a diversity of freshwater, marine, and terrestrial habitats
From the deepest marine sediments to soils in your backyard

Distinguishing Features

The Annelids are coelomate and triploblastic.
Bilaterally symmetrical
They exhibit organ system level organization. (when two or more organs work together for a specific function).
Their body is segmented.
Do have parapodia for locomotion
Invertebrate
Long cylindrical shaped bodies made up of many similar segments
Has Chaetae (setae) (bristles for anchorage, movement and sometimes defence)
No hard skeleton exoskeleton (unlike Arthropoda)
No antennae, no appendages (legs)
No obvious head end

Annelids are divided into 3 groups (2 of which are terrestrial)

Class: Oligochaeta - Earthworms
Class: Hirudinidea - Leeches
Class: Polychaeta (pol-ee-keets) - Marine worms

Subclass: Echiura Spoon Worms
Subclass: Errantia Free Swimming Worms
Subclass: Sedentaria Sedentary worms

Kingdom: Animalia

Phylum: Annelida

Class: Polychaeta

Subclass: Echiura

Order: Echiuroidea

Suborder: Bonelliida

Family: Ikedidae

Ikeda sp 1

Sand Worm

Kingdom: Animalia

Phylum: Annelida

Class: Polychaeta

Subclass: Errantia

Order: Phyllodocida

Suborder: Aphroditiformia

Family: Aphroditidae

Aphrodita australis

Sea Mouse

Phylum Annelida

Class: Polychaeta

SubClass: Errantia

Order: Phyllodocida

Suborder: Nereidiformia

Family: Syllidae

Subfamily: Syllinae

Megasyllis corruscans

Orange Worm

Phylum: Annelida

Class: Polychaeta

Subclass: Sedentaria

Infraclass: Canalipalpata

Order: Sabellida

Family: Sabellidae

Subfamily: Myxicolinae

Tribe: Miniclimate

Myxicola infundibulum