Pseudodiaptomus sheni sp. nov., one new species of Pseudodiaptomidae from the Jiulong River Estuary, Fujian

Abstract

The samples of copepods were collected from the estuary of Jiulong River during September 2013 to September 2017. One new species of Pseudodiaptomidae, Pseudodiaptomus sheni Guo & Wang, sp. nov., which had been identified as the saccupodus type of P. poplesia (Shen, 1955) by Chen and Zhang (1965) and Shen (1979), is described. The differences between this new species and P. poplesia are as follows:(1) cephalosome rounded anteriorly, while that of P. poplesia narrowly protruded in dorsal view; (2) female posterolateral corner with distinct bump postermedially; (3) the posterior process of female genital operculum pointed and longer than that of P. poplesia; (4) the outer terminal 2nd and 3rd setae basally swollen on female caudal rami; (5) the first exopod segment of female fifth leg with distomedial acute projection, while that of P. poplesia with blunt one; 6) medial triangular projection on the endopod of male left fifth leg elongated and longer than that of P. poplesia. The mitochondrial cytochrome oxidase subunit Ⅰ (mtCOI) gene sequences support the conclusion based on morphological data, with distinct divergence values 17.4% to 19.5% between P. sheni and P. poplesia. The new species is named in honor of Prof. Chia-jui Shen (1902-1975), a senior crustacean taxonomist of Institute of Zoology, Chinese Academy of Sciences. All type specimens are deposited in Museum of Marine Science and Technology, Xiamen University.