Teod ehk kõhtjalgsed (Gastropoda) on loomade riiki limuste hõimkonda kuuluv klass. Terminit "tigu" võib kasutada kogu kõhtjalgsete klassi tähistamiseks, kuid argitähenduses peetakse tigude all tihti silmas kopstigude seltsi esindajaid. http://www.veeseire.ee/vesi The Gastropoda or gastropods, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. The class Gastropoda includes snails and slugs of all kinds and all sizes from microscopic to Achatina achatina, the largest known land gastropod. There are many thousands of species of sea snails and sea slugs, as well as freshwater snails, freshwater limpets, land snails and land slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Late Cambrian. There are 611 families of gastropods known, of which 202 are extinct and appear only in the fossil record. http://www.minest.ee/loodusblogi https://www.facebook.com/groups/loodusblogi https://www.flickr.com/groups/loodusblogi https://www.pinterest.com/veeseire/loodusblogi/ https://plus.google.com/collection/kBFXWE
