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

ABSTRACT

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.

SUBJECT EDITOR:

• Tomas Cedhagen

KEYWORDS:

• Monothalamids
• allogromiids
• taxocene structure
• biodiversity
• inter-regional patterns
• Black Sea

Acknowledgements

The authors are thankful to Lyudmila Lukyanova for help with processing of the samples, Tat’yana Revkova for her assistance with formatting of the tables. We are grateful to Vitaliy Timofeev for help in improving the quality of the images and to all our colleagues involved in sampling during the research vessel cruise. We also much appreciate two anonymous referees for valuable comments and discussion which improved the manuscript substantially.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was carried out in the Benthos Ecology dept., IMBR RAS, within the framework of the state assignment on the theme № 0828-2018-0002 ‘Ecological and phylogenetic aspects of formation and anthropogenic transformation of biodiversity and resource potential of the ecosystems of the Azov-Black Sea basin and other regions of the World Ocean’ (state registration № AAAA-A18-118020890074-2).