siculan.
/ˈsɪkjuːlə/ Palaeontology.
The small conical or dagger-shaped structure secreted by and containing the initial member of a colony of graptolites.
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the world > animals > invertebrates > zoophyte > [noun] > fossil zoophyte > of genus Graptolites > colony of conjoined graptolites > structure containing initial member of
sicula1893
1893 Lunds Univ. Årsskrift XXIX. xii. 3 The sicula is seen to project from the right side obliquely upwards towards the median groove, thus separating the rounded bases of the two moieties of the rhabdosoma.
1895 I. K. Funk et al. Standard Dict. Eng. Lang. II. Sicula.., the earliest stage of a graptolite when it is a small triangular corneous body.
1910 Encycl. Brit. XII. 366/2 It is the general practice of palæontologists to regard each graptolite polypary (rhabdosome) developed from a single sicula as an individual of the highest order.
1970 R. M. Black Elements Palaeontol. xiv. 211 The sicula was secreted by the first members (a zooid) of the colony and the thecae were formed by the subsequent zooids by a process of budding.
This entry has not yet been fully updated (first published 1933; most recently modified version published online December 2020).
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