Zoological Studies

Vol. 55, 2016

(update: 2016.8.3)

Two New Echinoderes Species (Echinoderidae, Cyclorhagida, Kinorhyncha) from Nha Trang, Vietnam

doi:10.6620/ZS.2016.55-32

Hiroshi Yamasaki

Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Nakagami, Okinawa 903-0213, Japan

(Received 13 November 2015; 4 April 2016)

Hiroshi Yamasaki (2016) No kinorhynchs have previously been reported at the species level from Vietnamese waters. Two new species in the Echinoderes coulli-group, Echinoderes regina sp. nov. and Echinoderes serratulus sp. nov., are described from Nha Trang, Vietnam, Southeast Asia. Echinoderes regina sp. nov. is characterized by the large trunk (451-503 μm), a middorsal spine on segment 4, sublateral spines on segments 6 and 7, lateroventral tubules on segment 5, sublateral tubules on segment 8, laterodorsal tubules on segment 10, large sieve plates on segment 9, a primary pectinate fringe with fringe tips wider middorsally to ventrolaterally and thinner ventromedially on segments 2-9, and lateral terminal spines (15-20% of trunk length). Echinoderes serratulus sp. nov. is characterized by a middorsal spine on segment 4, sublateral spines on segments 6 and 7, lateroventral tubules on segments 5 and 8, midlateral tubules on segment 9, laterodorsal tubules on segment 10, large sieve plates on segment 9, primary pectinate fringes with long fringe tips ventrally on segments 1-9, with the ventromedial tips obliquely orientated, pointing towards the midventral line on segments 2-5, and short, plump lateral terminal spines (12-15% of trunk length).

Key words: Echinoderes coulli-group, Meiofauna, Southeast Asia, Taxonomy, distribution.

*Correspondence: E-mail: h.yamasaki@meiobenthos.com; hiroshi.yamasaki@mfn.berlin.de