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Species commonly assigned to the cheilostome bryozoan genus Onychocella Jullien, 1882 are numerous in deposits of Late Cretaceous age. Among these are 15 species with wide stratigraphical and geographical distributions that are better placed in the genus Rhagasostoma Koschinsky, 1885. These are used here to show similarities between Late Cretaceous bryozoan associations from Western Europe and Central Asia. Type and additional material was examined of several species from the Turonian to the Maastrichtian of Western Europe, including material studied by R.M. Brydone, E. Voigt and T.A. Favorskaya and undescribed material from the Campanian and Maastrichtian of several localities in Eastern Europe and Central Asia. The new species Rhagasostoma brydonei sp. nov., R. aralense sp. nov. and R. operculatum sp. nov. are introduced. New and published data on the morphology and the stratigraphical and geographical distributions of R. inelegans (Lonsdale, 1850), R. gibbosum (Marsson, 1887), R. gibbosulum Brydone, 1936, R. rowei (Brydone, 1906) and R. mimosa (Brydone, 1930) is presented.
The taxonomy of cyclostome bryozoans is founded on characters of the skeleton, but molecular sequence data have increasingly shown that established higher taxa are not monophyletic. Here we describe the skeletal morphology of a new species from Guadeloupe (French West Indies) with erect ramose colonies consisting of long, curved zooids that are typical of the suborder Cerioporina among living cyclostomes. However, molecular evidence from nuclear ribosomal RNA genes 18S and 28S places the new taxon in the suborder Rectangulata, where this colony-form has not been previously recorded. It nests firmly within the genus Disporella Gray, 1848, in a strongly supported clade that also includes Plagioecia patina (Lamarck, 1816) (Tubuliporina) and the sister taxa Doliocoitis cyanea Gordon & Taylor, 2001 (Rectangulata) and Favosipora rosea Gordon & Taylor, 2001 (Cerioporina). The short and robust branches of the new Guadeloupe cyclostome, here named Disporella guada Harmelin, Taylor & Waeschenbach sp. nov., are well adapted to life in shallow rocky sites exposed to severe wave action, which appear to be its exclusive habitat.
Microporella Hincks, 1877 is one of the most diverse genera of cheilostome bryozoans, containing more than 150 named species. Distributed globally since the early Miocene, the majority of species of Microporella have sheet-like colonies encrusting hard and / or ephemeral substrates, while a limited number of species have erect bifoliate colonies starting from an encrusting base. Herein, the four nominal species of erect bifoliate Microporella (M. bifoliata, M. hastigera, M. hyadesi and M. ordo) are revised, and one new Pliocene (M. tanyae sp. nov.) and three new Recent species (M. ordoides sp. nov., M. lingulata sp. nov. and M. modesta sp. nov.) are formally described. Furthermore, the lectotype and paralectotypes were designated for M. bifoliata and M. hastigera. An additional Recent species, Microporella sp. 1, is also described and illustrated but left in open nomenclature owing to the absence of ovicells in the single available fragment. Although the molecular phylogeny of Microporella has yet to be resolved, the diversity of character states present among the erect bifoliate species described here suggests that this colony growth-form is not monophyletic but has evolved on multiple occasions.