A study of the Upper Ordovician trepostomate bryozoans belonging to the families Amplexoporidae and Monticuliporidae, from the eastern Anti-Atlas of Morocco, is presented here. They occur in the marly to fine-grained limestone, intermediate unit of the Khabt-el-Hajar Formation, late Katian in age, representing outer-ramp depositional environments. They inhabited the highest paleolatitude known for a bryozoan fauna during the Ordovician, estimated at more than 65–70ºS. A total of 11 species of the generaAnaphragma,Atactoporella,Homotrypa,Monotrypa,Monticulipora, andPrasoporaare described. Three species are already known from the equatorial-tropical paleocontinents of Baltica, Laurentia, and Siberia:Anaphragma mirabile,Monotrypa jewensis, andPrasopora falesi. Four new taxa are described:Anaphragma undulata,Atactoporella moroccoensis,Monticulipora globulata, andMonticulipora irregularis.The two species ofAnaphragmaand the one ofAtactoporelladisplay significantly larger zoarial sizes than congeneric species, representing gigantism among bryozoans. Polar gigantism is rejected for the two species ofAnaphragmaas is gigantism related to photosynthetic endosymbionts. An alternative proposal for their giant size is their long zoarial life span due to their well-balanced, robust branching form, with a relatively wide basal supporting surface, adapted to unconsolidated substrates in environments below wave base. Their great stability in outer-ramp environments, with infrequent storms, would allow the zoaria to grow for an extended time and reach large sizes before being overturned and buried.Atactoporella moroccoensis, has both zoaria and zooecia gigantic, suggesting a hypothesis of polar gigantism.

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The upper Katian (Upper Ordovician) bryozoans from the Iberian Chains (NE Spain) are described. Twenty-three species are identified, five of them are new, seven were already identified in other paleocontinents and Mediterranean localities, four are provisionally referred to other known species, and seven are undetermined species. All of them belong to 22 genera assigned to 14 families, and to one incertae sedis genera. The five Stenolaemata orders (Cryptostomata, Cyclostomata, Cystoporata, Fenestrata and Trepostomata) are represented here, Trepostomata and Cryptostomata being the most abundant and diverse. The trepostome family Halloporidae is the one with the highest diversity, with 4 genera and 5 species described here. The five new species are the cryptostomes <i>Pseudostictoporella iberiensis </i>sp. nov., characterized by the presence of superior hemisepta in the autozooecia, and <i>Prophyllodictya javieri </i>sp. nov., also characterized by the presence of superior hemisepta in the autozooecia and by its small exilazooecia; the cystoporate <i>Ceramoporella inclinata </i>sp. nov., whose main diagnostic character is the constant autozooecial inclination; and the trepostomates <i>Dybowskites ernsti </i>sp. nov., easily recognizable by its large autozooecial and mesozooecial apertures, as well as by its large acanthostyles and <i>Trematopora acanthostylita </i>sp. nov., mainly characterized by the absence of diaphragms in its mesozooecia and numerous, large acanthostyle

Several studies have revealed temperature-related patterns in recent bryozoans, both in the chemical composition of the skeleton and in the morphological characters of the colonies, but comparable studies on Palaeozoic bryozoans are lacking. In this paper a statistical analysis of the morphological differences is undertaken between congeneric species of some Ordovician bryozoans from warm-and cold-water settings. For this study ten eurythermic cosmopolitan bryozoan genera from the Upper Ordovician were selected from the Mediterranean, Avalonia, Baltic and Laurentia-Siberian provinces. These genera are: Ceramopora and Ceramoporella (Cystoporata); Diplotrypa, Eridotrypa, Hallopora, Heterotrypa, Monticulipora and Trematopora (Trepostomata); Graptodictya (Cryptostomata); and Kukersella (Cyclostomata). The study involved 154 samples belonging to 104 different species. Twenty-eight morphological characters were measured, although only 21 were used in the final statistical analysis. Univariate (t, F, Kolmogorov-Smirnov and Mann-Whitney tests), multivariate discriminant and multivariate ordination (Principal Coordinates, Principal Components, Correspondence, and Detrended Correspondence) analyses were performed on the data. For the univariate and multivariate discriminant analyses, the total set of samples was divided a priori into cold-and warm-water subsets based on palaeolatitude: samples from the Mediterranean province were attributed to the cold-water subset, whereas samples from Avalonia, Baltic and the Laurentian-Siberian provinces were included in the warm-water subset. For the multivariate ordination analysis no a priori grouping by water temperature was imposed, and the aim of these analyses was to test whether different samples were correctly arranged along a water temperature gradient. The univariate statistical analysis showed that there are clear morphological differences between cold-and warm-water species in six of the ten Late Ordovician bryozoan genera analysed in this study, although these differences are only evident for some of the characters used, and only when the analysis is performed on individual genera. The best characters to differentiate species by water temperature are those related to the size of the zooidal polymorphs, especially the diameters of the autozooecia, mesozooecia and exilazooecia. With the exception of one genus (Trematopora), cold-water species have larger zooids. The discriminant analysis was able to classify correctly as warm-or cold-water 100% of the samples for two genera, slightly below 95% for two other genera, and between 67% and 90% for the remaining six genera. Finally, the multivariate ordination analysis was able to separate species by palaeogeographical province in some genera, but these provinces were not correctly arranged along a palaeolatitudinal gradient using any of the methods used. • Key words: bryozoans, cosmopolitan genera, latitudinal adaptations, univariate and multivariate statistical analysis.

Lingulate brachiopod fauna from Suchomasty Limestone (upper Emsian, P. serotinus Zone) are examined. Eleven species were observed, of which Kosagittella robusta, Chynithele intermedia, Lochkothele rugellata and Praeohlertella lukesi are described as new taxa. Associated Opatrilkiella kobyla, Havlicekion frydai and Opsiconidion coralinus were described previously from the Chýnice Limestone of the Barrandian area. Four taxa are left in open nomenclature including further evidence of the siphonotretid Orbaspina in the upper Emsian. The composition of the fauna shows distinct difference to other Emsian and Eifelian lingulate brachiopod faunas of the Koněprusy area of the Barrandian. •