<Tr> <Td_colspan="2"> <P> Condylipoda Latreille, 1802 </P> </Td> </Tr> <P> Condylipoda Latreille, 1802 </P> <P> An arthropod (/ ˈɑːrθrəpɒd /, from Greek ἄρθρον arthron, "joint" and πούς pous, "foot") is an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and paired jointed appendages . Arthropods form the phylum Euarthropoda, which includes insects, arachnids, myriapods, and crustaceans . The term Arthropoda as originally proposed refers to a proposed grouping of Euarthropods and the phylum Onychophora . Arthropods are characterized by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate . The arthropod body plan consists of segments, each with a pair of appendages . The rigid cuticle inhibits growth, so arthropods replace it periodically by moulting . </P> <P> Their versatility has enabled them to become the most species - rich members of all ecological guilds in most environments . They have over a million described species, making up more than 80 per cent of all described living animal species, some of which, unlike most other animals, are very successful in dry environments . </P>

What type of skeleton does a spider have