Meiofauna Taxa: A Systematic Account

Many of the zoological groups belonging to the meiobenthos are omitted in zoology textbooks, or they are commented upon as “small and isolated groups” in a few lines of small print. However, they often represent anatomically fascinating and phylogenetically important taxa. Particularly in the “new animal phytogeny” based on the analysis of gene sequences or whole genomes, small meiobenthic groups such as rotifers, gnathostomulids or tardigrades represent important and much disputed bridging taxa, whose links with larger phylogenetic groups are much disputed (see Jenner 2004; Philippe et al. 2005). In this account, the reader will find freshwater taxa more briefly presented than the marine groups (see Rundle et al. 2002 for more details on the freshwater taxa). In this ecologically oriented overview, phylogenetic discussions will be presented in general features only. My descriptions of meiobenthic taxa (including gross diagnostic aspects and omitting many anatomical details) cannot substitute for reading textbooks or the primary literature. The figures given herein depict only some selected forms and should not be used for more detailed identification. Each paragraph begins with taxonomic data, continues with biological, ecological and distributional comments, and ends with some aspects of relationships and phytogeny.