The authors present a taxonomic study of benthic diatoms collected from coastal rocks in seven northern Mediterranean sites (Italy, Spain, Greece, Turkey) in spring of 2010. An iconographic catalogue of high-quality SEM and light microscopic images, plus detailed taxonomic, nomenclatural and bibliographic information, are provided as a practical reference for further taxonomic and floristic studies on 91 plates. 120 representative diatom taxa, among them several poorly known species, selected from 23 samples, are described in terms of their abundance. The authors provide detailed information on the type material of each diatom species, a list of synonyms, a comparison of morphometric data provided in the literature (in tables) and a series of iconographic SEM-images which illustrate the taxon’s morphological variability, plus an exhaustive list of references. Nomenclature, taxonomy and systematic position of the described taxa are updated. Eight taxa are described as new to science and another seven are nomenclaturally recombined. Eight taxa are new records for the Mediterranean Sea and for five taxa Scanning Electron Microscope (SEM) images are presented for the first time.

An exhaustive reference list and indices of taxa conclude this volume and make it a valuable source of information for biologists working on benthic diatoms in general, not only of the Mediterranean region.

Benthic diatoms are the most abundant and diversified part of marine phytobenthos playing important role in the marine ecosystems. These organisms are used as water quality indicators as well as in palaeoecological reconstructions due to their ecophysiological features.

The Mediterranean Sea is a marine diversity hot spot having several endemic species. However, for long time its ecosystems have been exposed to serious anthropogenic impacts including habitat loss and degradation, fishing, pollution, climate change, eutrophication and the establishment of alien species.

This volume presents a taxonomic study on the coastal benthic diatoms of the Mediterranean Sea. Samples were taken from coastal rocks at seven locations in Spain, Italy, Greece and Turkey including the coasts of Adriatic and Aegean Seas. The authors describe 120 selected taxa (belonging to 73 different genera) including not only the most abundant and more widely distributed taxa in the study area but rare taxa as well as eight new records for the Mediterranean Sea. Seven species and one form are new to science, seven taxa are nomenclaturally recombined and for five taxa scanning electron microscopic micrographs are published for the first time. A quickfinder table summarising taxonomic, floristical and nomenclatural novelties helps the reader comprehend the results.

The authors found genera Cocconeis, Amphora (including Halamphora) and Licmophora to have very high species richness. Beside epilithic diatoms euplanktonic forms (e.g. Actinocyclus, Stephanodiscus, Coscinodiscus) were also detected and are presented in this study.

Unidentified taxa (22 taxa ascribed to the most similar species found in the literature and 63 taxa identified to genus level) are also presented. Most of these taxa belong to the genera Navicula and Nitzschia of which taxonomy are still need further investigations.

The authors applied updated nomenclature, taxonomy and systematic position for identification taxa. Not only qualitative but quantitative (morphometric) analyses were performed on the samples using unambiguous terms describing the three dimensions of the valves/frustules. The results were compared to measurements published in other works and in most cases noticeable differences were shown that could be hardly assigned to the same species perhaps reflecting cryptic diversity. This result is presented on the example of Tryblionella coarctata.

The information on the research is provided in the form of a regular paper. The taxonomic part of the book contains the following information for each species: basionym (if it is different from the currently accepted specific name), information on the type material including type locality, list of homo – and/or heterotypic synonyms, a table for comparison measured morphometric parameters to the data from the literature, a list of bibliographical references containing illustrations (drawings or LM/SEM photographs). In order to acquire these data the authors used phycological databases, technical reports and internet resources beside the scientific literature. Formal morphological descriptions are not included in this section. The taxon names are supplemented with the authors’ name, the year of publication and the number of the page/plate/exsiccata containing the validating diagnosis or illustration. The reference corresponding to the taxon names are provided in literature cited.

The morphological variability of the described taxa are illustrated on 572 light and 212 scanning electron micrographs arranged in 91 plates. Figure legends involve the taxonomic and nomenclatural information.

On the whole, this book provides a valuable collection of information on benthic diatoms living on the Mediterranean coasts. It can be recommended to everyone working with this group of algae, especially to those who deal with morphometric questions.

M. Duleba

Acta Botanica Hungarica 56 (3-4)

In the 60th volume of Bibliotheca Diatomologica authors Irene Álvarez-Blanco and Saúl Blanco summarize results of their research of benthic diatoms collected in 2010 at European coasts and adjacent islands of Mediterranean Sea at seven locations from Spanish Murcia on the west, through Italy and Greece up to Turkish Kusadasi on the east.

Altogether 120 taxa were identified to specific or infraspecific level. Besides, other 22 taxa were ascribed “cf” to the most similar species found in literature, and 63 taxa were identified to generic level so far. Most of these unidentified taxa belong to the genera Navicula and Nitzschia, whose taxonomy in marine and brackish waters is still not well resolved. Besides typical sea benthic taxa, included are also sea planktonic species and freshwater species captured in collected samples.

Taxa names are cited “in full”, i.e. followed by the year of publication and the number of the page/plate containing the validating diagnosis and/or illustration. Great attention is paid to giving the list of homotypic and heterotypic synonyms completed by extensive list of references to illustrations. At species with more infraspecific taxa is under the species name apparently understood only typical variety or form, as it is recently commonly used, however not in agreement with the rules of International Code of Nomenclature for algae, fungi and plants (Melbourne Code). Another important part of the text on particular taxa is a table of main morphometric data containing own data as well as precise excerpt from literature. In some cases information considerably differs, which illustrates that names of many taxa are used with different taxonomic concept. Taxonomic part also includes descriptions of seven new species and one new form new to science discovered thanks to careful examination using SEM. Seven taxa were nomenclaturally recombined.

In the genus Achnanthes there is described a new species Achnanthes eureka from the Rhode Island. Tryblionella coarctata f. densestriata with denser striae is a new taxon from Spanish Murcia. Not only marine diatomists will be interested in newly proposed name Tryblionella kuetzingii Álvarez-Blanco & S.Blanco commonly known as Nitzschia constricta (Kütz.) Ralfs in Pritchard 1861, or Tryblionella constricta (Kütz.) Poulin in Poulin et al. 1990. Seminavis insignis is another new species originating from the coast of Isla de Mallorca. Halamphora staurophora (Juhl.-Dannf.) Álvarez-Blanco & S.Blanco is a new name for Amphora staurophora Juhl.-Dannf. and Halamphora kolbei (Aleem) Álvarez-Blanco & S.Blanco is a new name for Amphora kolbei Aleem. In the genus Halamphora there is described another new species Halamphora cejudoae from Spanish coast near Murcia and proposed are four new combinations: Halamphora capitata (Hagelst.) Álvarez-Blanco & S.Blanco for Amphora bigibba var. capitata Hagelst. 1939, Halamphora kolbei (Aleem) Álvarez-Blanco & S.Blanco for Amphora kolbei Aleem 1950, Halamphora staurophora (Juhl.-Dannf.) Álvarez-Blanco & S.Blanco for Amphora staurophora Juhl.-Dannf. 1882, and Halamphora wisei (Salah) Álvarez-Blanco & S.Blanco for Amphora wisei (Salah) Simonsen 1962. Another new name is Fallacia forcipata var. densestriata (A.W.F.Schmidt) Álvarez-Blanco & S.Blanco for Navicula forcipata var. densestriata A.W.F.Schmidt 1874-1959. Other new species from Isla de Mallorca are Amphora alaeziarum and Brockmanniella tethys, whose genus was up to now monotypic. Hyalosynedra hyalina is a new name suggested for Synedra laevigata var. hyalina Grunow 1877. From Spanish Denia originate other two new species: Hyalosynedra hesperia and Hyalosynedra sublaevigata.

The iconographic section brings high quality LM and SEM pictures on 91 plates. Legends often contain brief notes on morphological features. Enclosed is very detailed taxonomic index comprising all used synonyms and exhaustive list of references counting 75 pages.

This publication is another important diatomological work, whose detailed taxonomic, nomenclatural and bibliographic information with detailed and critical elaboration of synonymic, can serve as a useful tool for all further diatomological studies dealing with benthic diatoms, not only the marine ones.

Markéta Fránková, Petr Marvan

Algological Studies 145/146 (2014)