In the field of zoology, aspadix (/ˈspeɪdɪks/SPAY-diks;pl.:spadices/ˈspeɪdɪsiːz/SPAY-dih-seez,/speɪˈdaɪsiːz/spay-DY-seez) is asecondary sexual organ found in somecephalopods andhydrozoans. In the genusNautilus, the spadix is a compositeerectile organ in the male located in the oral region which is composed of four highly modified tentacles and which is paired with a somewhat smallerantispadix that is also composed of fourtentacles. The spadix is normally a concealed organ but quickly becomes distended upon the animal's death. The exact function of the spadix and antispadix inNautilus is not yet known.[1]
Cephalopod anatomy | ||||||||||||||
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| Shell |
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| Mantle & funnel |
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| Head & limbs |
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| General | ||||||||||||||
Developmental stages:Spawn →Paralarva (Doratopsis stage) → Juvenile → Subadult → Adult •Egg fossils •Protoconch (embryonic shell) | ||||||||||||||
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