A new species of Stylicletodes Lang, 1936 (Copepoda: Harpacticoida: Cletodidae) from the East China Sea, including an updated key to species and synopsis of distribution records Author Ma, Lin 0000-0001-8906-8498 Department of Marine Organism Taxonomy and Phylogeny, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. malin @ qdio. ac. cn; https: // orcid. org / 0000 - 0001 - 8906 - 8498 & Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China. malin@qdio.ac.cn Author Liu, Qing He 0000-0001-8906-8498 Department of Marine Organism Taxonomy and Phylogeny, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. malin @ qdio. ac. cn; https: // orcid. org / 0000 - 0001 - 8906 - 8498 & Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang, China. hdqinghe @ 126. com; https: // orcid. org / 0000 - 0003 - 0832 - 4344 malin@qdio.ac.cn Author Li, Xin Zheng 0000-0001-8906-8498 Department of Marine Organism Taxonomy and Phylogeny, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. malin @ qdio. ac. cn; https: // orcid. org / 0000 - 0001 - 8906 - 8498 & Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China. & Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang, China. hdqinghe @ 126. com; https: // orcid. org / 0000 - 0003 - 0832 - 4344 & Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China. lixzh @ qdio. ac. cn; https: // orcid. org / 0000 - 0001 - 6344 - 6542 malin@qdio.ac.cn Author Huys, Rony Department of Life Sciences, The Natural History Museum, Cromwell Road, London SW 7 5 BD, U. K. text Zootaxa 2021 2021-10-12 5051 1 423 442 journal article 4029 10.11646/zootaxa.5051.1.17 5edc796d-8171-47cc-95d3-4a0b8fd89f53 1175-5326 5563831 168B0219-6287-4C93-B37F-0451BDAAB99F Key to species of Stylicletodes Lang, 1936 Both the latest dichotomous key by Bodin (1968) and the tabular key by Wells (2007) have been superseded. A new key to the seven valid species is presented below and rectifies oversights and misinterpretations contained in previous keys. Gómez (2000) pointed out the close similarity between S. stylicaudatus and S. oligochaeta ; comparison between these species is necessarily based on the male of the former and the female of the latter and restricted to caudal ramus morphology. 1. Anal operculum terminating in conspicuous, median, setular extension; armature elements on P 5 ♀ densely plumose...... 2 - Anal operculum rounded, without median, setular extension; armature elements on P 5 ♀ naked or sparsely pinnate........ 4 2. P1 enp-2 with one seta; P3 exp-3 with five setae/spines..................................... S. minutus Bodin, 1968 - P1 enp-2 with two setae; P3 exp-3 with six setae/spines....................................................... 3 3. P4 exp-3 with five setae/spines; P4 enp-2 with one seta........................................... S. wellsi sp. nov. - P4 exp-3 with six setae/spines; P4 enp-2 with two setae..................................... S. reductus Wells, 1965 4. P3–P4 exp-3 with five setae/spines....................................................................... 5 - P3–P4 exp-3 with six setae/spines........................................................................ 6 5. Caudal ramus extremely long and narrow, about half as long as length of body somites combined, divergent; seta VII originating from middle third of ramus..................................................... S. oligochaeta Bodin, 1968 - Caudal ramus distinctly shorter and wider; seta VII originating from proximal third......... S. stylicaudatus ( Willey, 1935 ) 6. Caudal ramus maximum length:width ratio 7–11, about as long as urosome; inner margin virtually straight, with long setules in proximal half; seta II reaching to about halfway ramus length; setae I–II arising from small outer margin protuberance................................................................................. S. longicaudatus ( Brady, 1880 ) - Caudal ramus maximum length:width ratio 4–5, about 60% of urosome length; inner margin convex in proximal half, without setular ornamentation; seta II reaching to posterior margin of ramus; setae I–II arising from conspicuous outer margin protuberance............................................................................. S. verisimilis Lang, 1965