Abstract
Three new gastrotrich species of the genus Tetranchyroderma are described sublittoral sandy bottoms of the Yellow Sea and Jeju Island in South Korea. Tetranchyroderma aethesbregmum sp. nov., which has a dorsal cuticular armature with pentancres only, is characterized by the peculiar shape of the head with a median trapezoidal lobe flanking three pairs of papillae. Tetranchyroderma megabitubulatum sp. nov. is clearly differentiated from other pentancrous species by the character combination of three pairs of cephalic tentacles, a pair of long dorsolateral adhesive tubes, and paired ‘foot’ ventral adhesive tubes. Tetranchyroderma insolitum sp. nov. is the only species possessing cuticular armature with tetrancres and triancres mixed, and also characteristic in having an earlobeprotrusion at the posterolateral corners of head.
References
Chang, C.Y. & Lee, J.M. (2001) Two new Tetranchyroderma gastrotrichs (Macrodasyida Thaumastodermatidae) from South Korea. Korean Journal of Biological Sciences, 5, 187–194.
Chang, C.Y., Lee, J.M. & Clausen, C. (1998a) Description of two new species thaumastodermatids (Gastrotricha, Macrodasyida) from Korea. Korean Journal of Biological Sciences, 2, 315–321.
Chang, C.Y., Lee, J.M. & Clausen, C. (1998b) Two new species of Thaumastoderma (Gastrotricha, Macrodasyida) from Korea. Sarsia, 83, 329–336.
Clausen, C. (2000) Gastrotricha Macrodasyida from the Tromsø region, northern Norway. Sarsia, 86, 357–384.
Hummon, W.D., Balsamo, M. & Todaro, M.A. (1992) Italian marine gastrotricha: I. Six new and one redescribed species of Chaetonotida. Bollettino di Zoologia, 59, 499–516.
Hummon, W.D. & Todaro, M.A. (2010) Analytic taxonomy and notes on marine, brackish-water and estuarine Gastrotricha. Zootaxa, 2392, 1–32.
Lee, J.M. & Chang, C.Y. (2002) Pseudostomella gastrotrichs (Macrodasyida, Thaumastodermatidae) from South Korea, with a brief review of the genus. Korean Journal of Biological Sciences, 6, 207–213.
Lee, J.M. & Chang, C.Y. (2003) Two new marine gastrotrichs of the genus Ptychostomella (Macrodasyida, Thaumastodermatidae) from South Korea. Zoological Science, 20, 481–489.
Lee, J.M. & Chang, C.Y. (2006) Marine gastrotrichs of the genus Diplodasys (Macrodasyida: Thaumastodermatidae) from Korea. Korean Journal of Systematic Zoology, 22(1), 109–115.
Lee, J.M. & Chang, C.Y. (2007) Two new marine gastrotrichs of the genus Tetranchyroderma (Macrodasyida: Thaumastodermatidae) from South Korea. Zoological Studies, 46(4), 474–482.
Lee, J. & Chang, C.Y. (2012) Crasiella clauseni, a new gastrotrich species (Macrodasyida, Planodasyidae) from Jeju Island, South Korea. Animal Systematics, Evolution & Diversity, 28(1), 42–47.
Lee, J.M., Hwang, U.W. & Chang, C.Y. (2009) A new marine gastrotrich species of the genus Ptychostomella (Macrodasyida: Thaumastodermatidae) from South Korea. Animal Cells & Systems, 13, 25–30.
Ruppert, E.E. (1991) Gastrotricha. In: Harrison, F.W. & Ruppert, E.E. (Eds), Microscopic Anatomy of Invertebrates, IV: Aschelminthes. John Wiley & Sons, New York, pp. 41–109.
Todaro, M.A. (2002) An interesting new gastrotrich from littoral meiobenthos (Long Beach Island, USA), with a key to species of Tetranchyroderma (Gastrotricha, Macrodasyida). Journal of Marine Biology Association of the United Kingdom, 82, 555–564.