Abstract 44 How to cite the abstract: Shao C., Song W., Berger H. (2011): A new species of Hemigastrostyla and notes on the non-monophyly of some oxytrichid genera (Ciliophora, Hypotricha). - VI European Congress of Protistology, 25–29 July 2011, Berlin, Germany, Abstract booklet, p. 113–114. Abstract. Supported by the Austrian Science Fund (FWF; Project P-23415-B17). A new species of Hemigastrostyla and notes on the non-monophyly of some oxytrichid genera (Ciliophora, Hypotricha) Chen Shao1, Weibo Song2, Helmut Berger3 1 Department of Biology and Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China 2 Laboratory of Protozoology, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China 3 Consulting Engineering Office for Ecology, 5020 Salzburg, Austria We found a new species of the genus Hemigastrostyla Song & Wilbert, 1997 in sandy sediments of the Jiaozhou Bay (Yellow Sea, China). Species of this marine/brackish genus have, like many other hypotrichs, basically an 18 frontal-ventral-transverse cirri pattern. Previously, all 18-cirri hypotrichs have been assigned to the oxytrichids because the characteristic pattern formed by the 18 cirri was interpreted as apomorphy of this group (Kahl 1932, Tierwelt Dtl. 25; Berger 1999, Monographiae biol. 78). Interestingly, the classification based on the ventral ciliature is in conflict with the dorsal kinety pattern and most gene sequence data, indicating that this complex 18-cirri pattern must have evolved much earlier in the Hypotricha tree, very likely already in their stemline (Berger 2008, MB 85). Due to these changes in hypotrich taxonomy, some genera - for example, Oxytricha and Hemigastrostyla - are obviously no longer monophyletic. Oxytricha granulifera Foissner & Adam, 1983 - type of the notoriously difficult genus Oxytricha Bory de Saint-Vincent, 1824 - has a dorsal kinety 3 fragmentation and dorsomarginal kineties. Consequently, Oxytricha species which lack the fragmentation (e.g., Oxytricha islandica Berger & Foissner, 1989; O. lanceolata Shibuya, 1930; O. longa Gelei & Szabados, 1950) have to be transferred to a (new?) genus outside the oxytrichids, but within the Dorsomarginalia Berger, 2006 which unify all hypotrichs having a dorsomarginal kinety. By contrast, Oxytricha species which lack both kinety fragmentation and dorsomarginal rows [e.g., Oxytricha geleii (Wilbert, 1986)] have to be placed outside the Dorsomarginalia, that is, near the base of the Hypotricha tree. Funded by the National Natural Science Foundation of China (Project 40906065; C. Shao, W. Song) and the Austrian Science Fund (FWF; Project P23415-B17; H. Berger). Key words: cell division, infraciliature, ontogenesis, phylogeny, Spirotricha, taxonomy Links Homepage www.protozoology.com Publication list of Helmut Berger Publisher Helmut Berger Monograph of hypotrichs FWF-Project P-23415-B17 Adobe to get the free Adobe Acrobat Reader Keywords: Hypotricha, Hypotrichida, Stichotrichida, stichotrichs, Asia, marine biology, Yellow Sea Top Dr Helmut BERGER Consulting Engineering Office for Ecology - Technisches Büro für Ökologie Radetzkystrasse 10, 5020 Salzburg, Austria, Europe Phone +43-(0)662-432538; Fax +43-(0)662-443139; email office@protozoology.com; http://www.protozoology.com