planorbiconic

English

planorbiconic (comparative more planorbiconic, superlative most planorbiconic)

(malacology, of a shell or fossil) Having a relatively flat spiral shell (intermediate between serpenticonic and spheroconic) in which the whorls touch (evolute to involute) and get larger as they get further from the center, causing the shell to have the profile of a mushroom when viewed from the side, without being so wide or involute that it is cadiconic.
- For quotations using this term, see Citations:planorbiconic.