Three new species of Dichromadora (Nematoda: Chromadorida: Chromadoridae) from the Yellow Sea, China

Abstract

Three new species of free-living marine nematodes belonging to Dichromadora Kreis: Dichromadora major sp. nov., Dichromadora multisetosa sp. nov., Dichromadora sinica sp. nov. from the Yellow Sea, China are described and illustrated. Dichromadora major sp. nov. is characterized by the combination of the presence of a clearly anterior pharyngeal bulb, crescent-shaped amphides, nine precloacal supplements, arcuate spicules and gubernaculum with a lateral swelling about the middle. Dichromadora multisetosa sp. nov. is characterized by the presence of a clearly anterior dorsal pharyngeal bulb and rounded posterior one, long somatic setae and a broad dorsal caudal apophysis of gubernaculum. Dichromadora sinica sp. nov. is characterized by the presence of double posterior pharyngeal bulb, four longitudinal files of lateral punctations, spicules with distal hook, four (3 + 1) precloacal supplements and paired subventral double-jointed postcloacal papillae in males.

Keywords:

• Dichromadora
• free-living marine nematodes
• new species
• China
• Yellow Sea

Acknowledgements

This work was supported by the National Science Foundation of China (no: 30770250). The authors are very grateful to Ms Guilan Qi and Ms Xiuqin Wu for their kind help in sample collection and slide making. Two anonymous referees provided valuable comments on this paper.