A section at Aktulagay (west Kazakhstan), in the Peri-Tethys realm, exposes mid-neritic to upper bathyal Ypresian marls, clays and silts. These range from Zone NP10 to early Zone NP14, with abundant and diverse microfossil assemblages. Multidisciplinary analysis has identified dinoflagellate cyst, calcareous nannofossil, planktonic and benthic foraminiferid and pteropod zones and events. Calibration of a key interval in the evolution of the shark Otodus has been possible for the first time. Episodic low-oxygen facies, including sapropelic clays widely distributed in Peri-Tethys, are represented here and can be placed within a detailed biostratigraphic framework. The current lithostratigraphic terminology is modified, with the introduction of the Aktulagay Formation. Paleoenvironmental aspects are discussed; five depositional sequences are tentatively identified. This section can be correlated in detail with the succession in the North Sea Basin, with implications for paleogeographic reconstructions. High-resolution biostratigraphic calibration between disparate fossil groups makes this a key reference section for northern mid-latitude Ypresian biostratigraphy.
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The fi sh fauna is presented from Asa Koma; a prehistoric site dated around 1800 cal BC and located in Djibouti near Lake Abhé. The site comprises numerous hearths from which the fi sh bones that form the majority of the faunal remains were recovered. Only two fi sh species occur, namely Oreochromis niloticus and Clarias gariepinus, which are also the two major taxa occurring in the saline lake today. The skeletal element distribution and the frequency of charred remains were analysed and, in addition, detailed size reconstructions were carried out. On the basis of modern skeletons from 47 tilapia and 39 Clarias, the metrical relationship between fi sh length and individual bone measurements (32 measuring distances for tilapia and 40 for Clarias) was established with the aid of the “least squares method”. The equations are all listed for future use by other researchers. The fi sh and other fauna do not allow a precise environmental reconstruction, but the large size of the Clarias possibly indicates less saline conditions than today. Using the reconstructed sizes of the fi sh from Asa Koma, modern data on the behaviour of the species, ethnographic and archaeological parallels, and palaeohydrological data, attempts are made to establish the most likely season of fi shing, the possible location of the fi shing grounds, and the fi shing methods that may have been used. Finally, the possible fi sh preparation and fi sh processing methods are discussed.
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The Galápagos ant fauna has long been understudied, with the last taxonomic summary being published almost a century ago. Here, a comprehensive and updated overview of the known ant species of the Galápagos Islands is provided with updated species distributions. The list is based on an extensive review of literature, the identification of more than 382,000 specimens deposited in different entomological collections, and recent expeditions to the islands. The ant fauna is composed of five subfamilies (Dolichoderinae, Dorylinae, Formicinae, Myrmicinae, and Ponerinae), 22 genera, 50 species, and 25 subspecies, although three species (Crematogaster crinosa Mayr, 1862, Camponotus senex (Smith, 1858), and Solenopsis saevissima (Smith, 1855)) are considered dubious records. Finally, an illustrated identification key of the species found in the archipelago is presented.
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RBINS Staff Publications 2023
