Derya Ürkmez

A brief look at the free-living Nematoda of the oxic/anoxic interface with a new genus record (Trefusia) for the Black Sea

Abstract In order to provide the first comparative source of nematofaunal data at the oxic/anoxic interface off the Sinop Peninsula, the southern Black Sea, a survey of meiofauna and nematode fauna was conducted in August 2011 aboard the exploration vessel (E/V) Nautilus with ROV during the Black Sea Expedition NA012. Higher meiofaunal taxa and nematode composition were investigated. Free-living marine nematodes were the most abundant group at each site. A total of 84 species were found, belonging to 23 families. The suboxic zone was dominated by the nematode Trefusia aff. longicauda (42%). This is the first record of the genus Trefusia De Man, 1893 for the Black Sea. Although many factors are likely to influence the changes in the meiofaunal abundance and the composition of nematode assemblages, we suggest that oxygen reduction indeed affected the meiofaunal abundance and the nematode composition, however, a particular preference of several taxa for extreme conditions may be suggested.

Within-year spatio-temporal variation in meiofaunal abundance and community structure, Sinop Bay, the Southern Black Sea

Abstract The first comprehensive meiobenthos study was carried out in Turkey, the Southern Black Sea (Sinop) from August 2009 to July 2010.Sediment samples were collected monthly at eight stations at 3 m and 10 m water depths located on four transects. A metal push core sampler (surface area 12.56 cm2 and length 10 cm was used to obtain the material. Meiofaunal abundance and composition were examined. The results revealed that the meiofaunal community consists of twenty five higher taxonomic groups. Four groups dominated the community; Nematoda, Harpacticoida, Foraminifera and Polyuchaeta. Spatial and temporal meiofaunal abundance fluctuated among stations and over time.

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

ABSTRACT 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

Meiobenthic Assemblages from the Southwestern Coast of the Black Sea, İğneada (Turkey)

Abstract Meiobenthic organisms were sampled for the first time from İğneada coasts, Turkey (Western Black Sea) in order to provide a base-line study on the meiobenthic community structure of the sampling area. Meiobenthos was found to be composed of 12 higher taxonomical groups: Nematoda, Harpacticoida, Polychaeta, recent hard-shelled Foraminifera, soft-shelled Foraminifera, Bivalvia, Gastropoda, Ostracoda, Turbellaria, Oligochaeta, Nemertea and Acari. Meiobenthic community was dominated by nematodes, harpacticoid copepods and hard-shelled foraminifera in the study area. Fifty two species of Nematoda, fifteen species of Harpacticoida and twelve species of living hard-shelled Foraminifera were identified. Six nematode species (Bathylaimus australis, Bolbolaimus murinae, Neochromadora poecilosomoides, Neochromadora sabulicola, Oncholaimellus mediterraneus and Onyx perfectus) are reported for the first time from Turkey although they are known to occur at the central Turkish Black Sea. Total density of the meiobenthos ranged between 67–757 ind. 10 cm−2 at stations. Nematodes showed densities ranging from 61 to 350 ind. 10 cm−2 which represented 25–92% of the total meiobenthos. Since the terrestrial part of the region is protected as a National Park and the coastal part has been proposed as a marine protected area, research should be intensified on the fauna of İğneada coastal waters to clarify the biodiversity of the area.