Crab

ARTICLE CONTENTS:  |  Links to Other Sites
Crab, common name for 2 groups of decapod ("ten-footed") CRUSTACEANS. The Anomura, including hermit, mole and lithoid crabs, have relatively normal abdomens. In true crabs, infraorder Brachyura, including genera Cancer and Carcinus, the abdomen is greatly reduced in size and is flexed beneath the thorax. Worldwide there are 4500 species inhabiting marine, freshwater and terrestrial environments. Crabs comprise one of the largest groups of the subphylum Crustacea; as individuals, they are among the largest of arthropods. Giant Japanese and Australian spider crabs, larger in size than the largest lobsters but weighing somewhat less, may have a claw span of over 3 m and weigh up to 14 kg. In Canada crabs are found in marine deep-water and in intertidal and estuarine environments on both coasts. Some, eg, East Coast snow or queen crab (Chionoecetes opilio) and West Coast Dungeness crab (Cancer magister), are of considerable economic value.

See also CRUSTACEAN RESOURCES.

Crab
Crab
Found near Holland Point, PEI (John MacGregor/Corel Professional Photos).

Author D.E. AIKEN


Links to Other Sites
Canadian Biodiversity Website
A great information source for all budding biologists. Learn about biodiversity theory, natural history, and conservation issues. From McGill’s Redpath Museum.

Aquaculture Atlas of Canada
Find out about Canada’s growing aquaculture industry in all ten provinces and in the Yukon. Features profiles of selected species.

0
0
Absolutely free, with over 40,000 articles in French and English, The Canadian Encyclopedia is the ultimate online resource for all things Canadian, from history, sports, arts, science, technology, and much, much more. Get started at www.TheCanadianEncyclopedia.com
Feature Articles
The Formation of the RCMP

The Dominion government's advertisement asked for volunteers "able to read and write either the English or French language" with "good antecedents" who were good horsemen...

INSIDE TCE

Gallery
Browse the rich visual resources of The Canadian Encyclopedia through thematic galleries of Canadian Art, History, Nature, People, and Science and Technology.
Interactive Resources
Illustrations, lively text, animations, sounds and games help make learning about Canadian history, art, geography, architecture and other topics entertaining as well as informative.
Canucklehead
The ultimate test of your knowledge of Canada, trivial and otherwise. You can choose from more than 60 dynamic quizzes with visual or text clues. Your scores depend on the speed with which you answer and the number of clues you need. Results are sent to you by email and high scores are posted on the site.
Timeline
This unique resource includes more than 6000 events from Canadian and world history. It can be searched by era, subject, keyword or date. To find out what happened on your birthday, select the month and day of your birth.
100 Greatest Events
This selection of the 100 "greatest" events in Canadian history was made by editor in chief James H. Marsh to draw attention to events that have left an indelible memory in the minds of later generations.