Morphological changes associated with the growth of feather star Clarkcomanthus exilis (Echinodermata, Crinoidea)
Kohtsuka, H.; Okanishi, M. (2021). Morphological changes associated with the growth of feather star Clarkcomanthus exilis (Echinodermata, Crinoidea). Biogeography 23: 67-73. https://dx.doi.org/10.11358/biogeo.23.67
In: Biogeography. Biogeographical Society of Japan: Tokyo. ISSN 1345-0662, meer
|  |
| Trefwoorden |
Clarkcomanthus exilis (Rowe, Hoggett, Birtles & Vail, 1986) [WoRMS]
Marien/Kust |
| Author keywords |
Taxonomic character, Sagami Bay, Pacific Ocean, juvenile |
| Auteurs | | Top |
- Kohtsuka, H.
- Okanishi, M.
|
|
|
| Abstract |
The first description of the morphological changes associated with the growth of the feather star Clarkcomanthus exilis is presented here, based on external morphological observations. Of the three specimens, with arm lengths of ca. 14 mm, 60 mm and 90 mm, the following changes were recognized. Centrodorsal cirri sockets arise from the entire flank of the centrodorsal region and are arranged in 1-2 annular, irregular rows, but as they grow, one or two cirri sockets arise in each radial and change to an annular row; division series of juveniles range up to IBr (first division series), mainly IBr 2, IIBr 4 (3+4), and as they grow, the series range up to mainly IBr 2, IIBr 4 (3+4), and IIIBr 4 (3+4); the aboral color is crimson red, and there are several thick brownish-white lateral stripes with some color on the arms that have a characteristic round-centered pattern when the arms are spread out. However, as it grows, the brownish-white thick transverse stripes on the aboral surface of the arm become blurred and move to the sides, and the characteristic round-centered pattern disappears. This study newly revealed that the length of the cirri shortens as this species grows. On the other hand, coloration and the presence of small spines at the pinnular ends of the distal pinnule, arising from the arm distal, are proven to be stable and characteristic through from small to large individuals of this species. |
|
