In this study nearly 50 species of diatoms new to science, collected from lake sediments across the western USA, are presented for the first time. A total of thirty-eight raphid species are described (across eighteen genera), while one non-raphid pennate and nine non-pennate species are also described from these collections. Observations with light and scanning electron microscopy are offered for each taxon.
Nomenclatural and morphological details for previously known species encountered in the author's examination of these sediments are provided and indicate their distribution across the western USA.

80 plates, a taxon index and a comprehensive reference list round up this volume and make it a valuable source of information for biologists and palaeontologists working not only on American but also on diatoms worldwide.

Since the 19th century several researchers including European and American diatomists have described new diatom species from the inland waters of the United States. However, the characterisation of diatom flora of these territories is still in the period of discovery. Becoming acquainted with the diatom taxa living in these waterbodies and understanding their ecological characteristics is important because diatoms can be applied in water quality monitoring for both running and standing waters.

In the National Lakes Assessment program a thousand lakes of the United States were evaluated based on benthic diatoms from sediment core samples. In this book the authors present the diatom taxa of sediments from more than 200 lakes across the Western United States (12 states from North Dakota to California) investigated in the NLA program. Sixty-two taxa are described including 50 species (in 23 genera, mainly raphid pennates) new to science. Two new combinations are offered and one species (Navicula caldwellii) is reported for the first time from the USA.

The distinction between newly described and previously established taxa may appear to be slight. The reason for the use of such fine-grained taxonomic approach is that the authors took notice of the cases of the so-called “pseudo cryptic species” in diatoms. This term means species discovered an originally single, morphology-defined species using other (e.g. molecular) methods and their distinctive morphological features were defined after that.

The authors described the most new taxa from Oregon State due to the ultra pristine environments of the Cascade Mountains holding relict flora. This result shows the speciality of the Pacific Northwest of the United States. However, the diversity in the neighbouring California was much lower because of the many perturbed habitats.

The descriptions of taxa are included in the framework of a regular research paper involving introduction, materials and methods, results and discussion as well as general conclusion sections. In the taxonomic part light and in almost all cases scanning electron microscopic description in English, information on distribution across the study area and/ or comparison with similar taxa are provided for each taxon. For new species description in Latin, holotype and type locality, for new combinations basionym are also given. One taxon (Amphora sp.) could be identified only to genus level.

The descriptions of taxa are illustrated with good quality light and scanning electron microscopic photographs arranged on eighty plates. Highlighting certain distinguishing features these illustrations can help the understanding of the delineations. Overall, this volume provides a good insight into the diatom flora of the United States. It can be useful for everyone interested in the diatoms.

M. Duleba

Acta Botanica Hungarica 56 (3-4)

Vorliegendes Werk liefert in Form einer klassischen Monographie einen taxonomischen Überblick über die Diatomeenfl ora von 55 Seen aus 12 Bundesstaaten im Westen der USA von Kalifornien bis Nord-Dakota. Zu den mehr als 60 vorgestellten Taxa liefern die Verfasser detaillierte anatomische Beschreibungen sowie (im Fall neuer Taxa) Diagnosen, aber auch Informationen zur geographischen Verbreitung und zur Ökologie. Dabei dokumentieren die Verfasser die Anatomie der behandelten Taxa auf insgesamt 80 Tafeln mit aussagekräftigen lichtmikroskopischen und rasterelektronenmikroskopischen Aufnahmen.
Verfasser stellen die folgenden neuen Arten bzw. Kombinationen auf: Aulacosira singularia Benett & Kociolek, n. sp., A. pusilloides Laslandes & Kociolek, n. sp., A. spathulata Laslandes & Kociolek, n. sp., Thalassinosira kharsevicha Laslandes & Kociolek, n. sp., Cyclotella fourtaniera Laslandes & Kociolek, n. sp., C. indistincta Benett & Kociolek, n. sp., Handmannia annulata Kociolek, n. sp., Pseudostaurosira parvissima Kociolek, n. sp., Napela americana Kociolek, n. sp., N. exigua Thomas & Kociolek, n. sp., Cavinula oblonga Kociolek, n. sp., Craticula lowea Kociolek, n. sp., Placoneis potapovatea (Moghadam) Kociolek, n. comb., Eolimna vanlandinghamii Kociolek, n. sp., E. madida Kociolek, n. sp., Navicula cerevisia Laslandes & Kociolek, n. sp., N. confusa Laslandes & Kociolek, n. sp., N. infossa Laslandes & Kociolek, n. sp., N. rarissima Benett & Kociolek, n. sp., Hygropetra inopinata Thomas & Kociolek, n. sp., Neidium spectatum Kociolek, n. sp., Ne. quadratum Kociolek, n. sp., Ne. limnophilum Kociolek, n. sp., Ne. occidentale Kociolek, n. sp., Ne. hamiltoni Kociolek, n. sp., Pulchella porcata Kociolek, n. sp., Stauroneis limneticus Kociolek, n. sp., S. stoermeri (Reimer) Kociolek, nom. nov., Muelleria spauldinga Kociolek, n. sp., M. ambigua Kociolek, n. sp., Sellapora distincta Kociolek, n. sp., Pinnularia splendens Kociolek, n. sp., P. demersa Kociolek, n. sp., Gomphonema parvicapitulum Kociolek, n. sp., G. insuetum Kociolek, n. sp., Eucyonopsis inexpectata Kociolek, n. sp., Gomphosphemia americana Kociolek & Thomas, n. sp., G. indistincta Kociolek & Thomas, n. sp., Halamphora stoermeri Kociolek, n. sp., H. reimeri Kociolek, n. sp., H. americana Kociolek, n. sp., H. elongata Benett & Kociolek, n. sp., Nitzschia americana Benett & Kociolek, n. sp., N. destituta Benett & Kociolek, n. sp. und Surirella ruckia Benett, Laslandes & Kociolek, n. sp.
Das Werk liefert einen hervorragenden taxonomischen und biogeographischen, aber auch ökologischen Einblick in die Diatomeenfl ora ausgewählter Seen im Westen der USA. Dieser ist sicher nicht nur für Biologen, sondern auch für Paläontologen von großem Interesse, die sich mit dieser Algengruppe beschäftigen.

Dieter Uhl, Frankfurt am Main

Zentralblatt für Geologie und Paläontologie, Teil II, Jg. 2016 Heft 3-4