Description of Megastygarctides sezginii sp. nov. (Tardigrada: Arthrotardigrada: Stygarctidae) from the Turkish Black Sea coast and a key to the genus Megastygarctides

In this paper, Megastygarctides sezginii sp. nov., a new marine species from the Black Sea (Turkey), is described. Morphological and morphometric studies have revealed that M. sezginii sp. nov. is most similar to M. setoloso Morgan & O’Reilly, 1988, but differs from it through the presence of two types of fibrils, a lack of cuticle granulation, the presence of three lateral projections with fibrils, leg fibrils arranged in transverse stripes and the presence of clumps of fibrils near the clavae. In the studied environment, the new species is frequently found in summer and almost absent in winter. Additionally, a taxonomic key for all Megastygarctides species is presented.

http://zoobank.org/urn:lsid:zoobank.org:pub:53AA1D57-8700-4A18-9099-1CDDBAEB4D3A     

Educator’s Pipeline

Abstract

Roszak, Theodore, The Cult of Information. New York: Pantheon Books, 238 pages. $7.95 paperback.     

Soft-walled monothalamids (Rhizaria: foraminifera) of the Crimean shelf (Black Sea): taxonomic composition and inter-regional patterns of species diversity and distribution

We present new data on monothalamous (single-chambered) foraminifera from the Black Sea Crimean shelf zone between Karkinitsky Gulf in the west to the area near Kerch in the east. Within this region we recognized a total of 40 morphospecies; 8 are assigned, in some cases tentatively, to known species and another 9 to known genera, again sometimes tentatively. Twelve species (all undescribed) are reported here for the first time. The most abundant species are Psammophaga sp. (sensu Gooday et al. 2011), Goodayia rostellata Sergeeva & Anikeeva 2008 and Vellaria pellucida Gooday & Fernando 1992, each of which is evenly distributed in all studied areas. The highest species richness of monothalamous foraminifera was observed in the Yalta region. Based on a multivariate analysis of monothalamid assemblage structure and diversity indices [Shannon (H’), Margalef (D’), eveness Pielou (J’), Simpson (1-λ’) and rarefaction ES(n)], we recognized three groups of stations, corresponding to the Western, Southern and Eastern coasts of the Crimean peninsula. The monothalamid assemblages found in each of these coastal regions exhibit different structural features and are distinguished by certain characteristic species.     

Ionic dependence of adenosine uptake by isolated nerve endings from Torpedo electric organ

Pure cholinergic synaptosomes from the electric organ of Torpedo marmorata have a saturable adenosine uptake mechanism (calculated K_m, 3 μM; V_max, 24 pmol/min/mg prot.). In this preparation, high intracellular calcium elicited by increasing external calcium concentration, potassium depolarization, sodium-calcium exchange inhibition or divalent cation ionophore A23187 action, inhibits adenosine uptake into synaptosomes. The data presented in this paper are consistent with the interpretation that high intracellular calcium participates in the regulation of the high-affinity adenosine uptake system.     

Taxonomic composition and distribution of soft-walled monothalamid foraminifera in the area of Zernov’s Phyllophora Field (NW Black Sea)

We studied assemblages of soft-walled, single-chambered foraminifera (monothalamids) at eight stations in the area of Zernov's Phyllophora Field (ZPF) on the NW continental shelf of the Black Sea. This work is based on samples collected during Cruise 70 of the RV Professor Vodyanitsky and provides the first analysis of the taxonomic composition of monothalamids from this region. These delicate, poorly known foraminifera were found at all stations in the studied area. They were represented by nine forms that are identified to species or genus level as well as 14 undescribed species, nine of which are found in the Black Sea for the first time. Four species, Psammophaga sp., Vellaria pellucida, Goodayia rostellata and Krymia fusiformis, were most abundant, with Psammophaga sp. being the dominant species overall. Previous studies have suggested a link between members of this genus and eutrophication. There are a number of taxonomic parallels between these ZPF assemblages and those from the Adriatic Sea, e.g. the occurrence of the genera Goodayia, Psammophaga and Vellaria, although it is possible that some other taxa are endemic to the Black Sea.