This dataset contains the digitized treatments in Plazi based on the original journal article Chan, Ho-Yeung, Lee, Chen-Lu, Chen, Wei-Cheng, Chang, Chia-Hao, Shao, Yi-Ta, Pang, Ka-Lai (2026): Thecacera sesama sp. nov. (Nudibranchia, Polyceridae) from Taiwan, evident from morphology and phylogenetic analyses of the 16 S rDNA and cytochrome c oxidase I gene. ZooKeys 1279: 269-284, DOI: 10.3897/zookeys.1279.184298

Abstract

Thecacera sesama Chan & Lee, sp. nov. (Nudibranchia, Polyceridae) is described from north-eastern Taiwan based on an integrative taxonomic approach combining morphological and molecular data. The new species is distinguished from its congeners by a unique colour pattern consisting of a translucent white body covered with numerous small, round, black pigment spots and fewer, larger, yellow spots and five gills. While sharing a similar spotted colour pattern with Thecacera pennigera, the new species can be clearly distinguished by its significantly smaller body size (maximum length <3 mm). Phylogenetic analyses of two mitochondrial genes, cytochrome c oxidase subunit I (COI) and 16 S rRNA, confirmed it as a new species in Thecacera. The molecular data places Thecacera sesama sp. nov. as a sister species to Thecacera picta, with a significant interspecific COI divergence of 14.17 %. This discovery highlights the rich, yet under documented, marine biodiversity of Taiwan and underscores the value of combining traditional morphological examination with molecular phylogenetics for accurate species delimitation in cryptic nudibranch lineages.

GBIF url: https://www.gbif.org/dataset/9ca93a43-332f-41d1-a7b7-2761391261a8
Homepage: https://tb.plazi.org/GgServer/summary/196C55F9B6655578B3F48BFD07EFE631
Citation: Chan H, Lee C, Chen W, Chang C, Shao Y, Pang K, pensoft (2026). Thecacera sesama sp. nov. (Nudibranchia, Polyceridae) from Taiwan, evident from morphology and phylogenetic analyses of the 16 S rDNA and cytochrome c oxidase I gene. ZooKeys. Checklist dataset https://doi.org/10.15468/4ftdpr accessed via GBIF.org on 2026-06-11.