• Journal of Species Research
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• v.11 no.1
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• pp.22-28
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• 2022

Two crinoid specimens of genus Tropiometra were collected from Busan and Tongyeong by SCUBA diving on August 2010 and October 2011, respectively. The specimens were identified as Tropiometra macrodiscus (Hara, 1895), which belongs to the family Tropiometridae of superfamily Tropiometroidea. The genus Tropiometra AH Clark, 1907 comprises four species worldwide at present, and it has not been reported in Korea. Tropiometra macrodiscus was first described by Hara (1895) in Japan. It is difficult to distinguish T. macrodiscus from T. afra (Hartlaub, 1890), there has been confusion with examination of their phylogenetic positions in crinoid morphological classification. Despite this, T. macrodiscus can be distinguished from T. afra based on longer arms, stouter whole-body parts, magnificently larger numbers of cirrus, and numerous segments. The morphological characteristics of T. macrodiscus collected in Korea have been described, and DNA barcode region representing cytochrome c oxidase subunit I was obtained for its molecular phylogenetic analysis.