Monograph of the Hypotricha (Ciliophora). Part 5

Hypotrichous ciliates are a major group of the spirotrichs. At present they are very likely the best-studied group of ciliates, besides the typical model organisms Paramecium and Tetrahymena. The present project concerns the fifth, that is, penultimate part of the Monograph of the Hypotricha. Two parts are already published, namely the Oxytrichidae (Berger 1999, Monographiae Biol. 78: 1092 pages, without financial support) and the Urostyloidea (Berger 2006, Monographiae Biol. 85: 1319 pages; FWF-Project 14778); two parts are in press, namely the Amphisiellidae and Trachelostylidae (Berger 2007, Monographiae Biol., about 600 pages; supported by Austrian Academy of Sciences, APART Project) and the Kahliellidae (Berger 2008, Monographiae Biol., about 400 pages; APART Project). Volume 5 of the Monograph of the Hypotricha will contain about the half of the genera which are not treated in volumes 1 to 4, inter alia, Uroleptus and the Keronopsidae. Previously, Uroleptus has been assigned to the urostylids because of the zigzagging arranged ventral cirri. However, morphological and molecular biological data showed, that this classification was based on a convergence. An important apomorphy of the Keronopsidae is the division in cysts. The remaining pages of part 5, which will comprise about 500 printed pages, will be filled with small higher taxa and mainly monotypical genera. The last part (volume 6) of the series will contain, inter alia, a key to all species. The present project comprises the following points: The critical revision of the available data comprises the major part of the project. The experience of the author (many publications about hypotrichous and other ciliates, inter alia, 14 books with more than 8000 printed pages) and comprehensive preliminary works (e.g., indexation of more than 6000 papers about hypotrichs to species level; making of a permanently updated index to all names of hypotrichs at www.protozoology.com; making of a bibliography) simplify, respectively, are prerequisite to write such a comprehensive book series. Additional investigations (morphology; cell division; phylogenetic analyses; molecular biological analyses in cooperation with the Schlegel-group, University of Leipzig) on some species. The monograph of the Hypotricha (in total about 4000 pages) is not only an important reference book for specialists, but also a detailed source of information for biologists of other disciplines (e.g., ecology, molecular biology, physiology). Practitioners, for example, in the water quality management, need not waste a lot of time to search for the many individual papers which are distributed in many journals from throughout the world. The Monograph is written in English and therefore usable for everyone worldwide. It is published by Springer in the book series Monographiae Biologiace.

The Hypotricha are a group of the Ciliophora (= ciliates) which is common in freshwater, saltwater (sea, salt lakes), and soil. The ciliates are single-celled microorganisms with a true nucleus, which is composed of two components (macronucleus and micronucleus). Since 1758, the beginning of zoological nomenclature, about 1000 hypotrichs - distributed in about 200 genera - have been described. The last detailed revision of species was provided by Kahl (1932, Tierwelt Dtl., 25, 399-650). However, since then many new species have been discovered, mainly from soil and the sea, and a high number of the long-known species has been redescribed with modern methods. Mainly for that reason at thorough revision of the hypotrichs has been started about 25 years ago. Prior to the present project three volumes were already available (Oxytrichidae, Berger 1999, Monographiae Biologicae [MB, Springer Publisher] 78: 1092 S; Urostyloidea, Berger 2006, MB 85: 1318 S; Amphisiellidae and Trachelostylidae, Berger 2008, MB 88, 753 S), supported, inter alia, by the Austrian Science Fund FWF and the AAS. In the framework of this project (1 person, 3 years, 20 h per week) smaller, rather difficult subgroups of the hypotrichs have been treated, inter alia the Gonostomatidae and the Uroleptidae. The gonostomatids have been published in volume 4, together with the Kahliellidae (Berger 2011, MB 90, 755 S). Volume 5 of the monograph is still in process and will be published very likely in early 2012. The genus Gonostomum was already revised in volume 1 (Oxytrichidea); however, the new interpretation of morphological data on the basis of molecular trees resulted in new hypotheses. Accordingly, this and related genera (e.g., Wallackia, Paragonostomum) very probably to not belong to the oxytrichids, but they obviously split off near the base of the Hypotricha tree. The kahliellids are likely a heterogeneous group and characterised by the preservation of parental cirri and/or dorsal bristles in postdividers. The uroleptids, previously assigned to the urostyloids because in both groups the ventral cirri form a conspicuous zigzag pattern, belong to the so-called `non-oxytrichid Dorsomarginalia`, a paraphyletic group with a dorsal bristle row pattern which is somewhat more complex than that of the gonostomatids, urostyloids, and amphisiellids, but not so complex like that of the oxytrichids. The uroleptids are not only taxonomically difficult, but also nomenclaturally because Ehrenberg, who described the genus in 1831, did not fix a typical species; in addition, the subsequent fixation by Borror in 1972 is also not beyond dispute. Volume 5 is the penultimate part of the Monograph of Hyptotrichs. For details and publications see http://www.protozoology.com (projects).