Marine Biological Journal

The Kuban River basin, a new page in the expansion of the Asian clam Corbicula fluminea (O. F. Müller, 1774) (Bivalvia: Cyrenidae)

D. Vekhov — 2024-09-09

The invasive bivalve Corbicula fluminea (O. F. Müller, 1774) was found in the Kuban River basin. Three live Asian clams were recorded in the Protoka River near the settlement of Grivenskaya (Krasnodar Krai) in the autumn of 2022. Assumably, high invasive potential of this species and its ability to withstand salinity up to 5‰ will allow the clam to inhabit not only freshwater bodies, but also estuarine zones of rivers and Azov limans. C. fluminea is a food item for fish, and its naturalization can increase the resource potential of water bodies in the south of Russia.

The first findings of new species of amphipods in the Sea of Azov

V. Grintsov — 2024-09-09

In 2022–2023, 8 species and 4 genera of Amphipoda new to the Sea of Azov were found near the Cape Kazantip (the Crimea; Golubniki, Russkaya, and Shirokaya bays). All specimens are stored in IBSS Collection of Hydrobionts of the World Ocean. The following species were recorded: Ampelisca sevastopoliensis Grintsov, 2011 (the family Ampeliscidae); Apohyale crassipes (Heller, 1866) (Hyalidae); Microprotopus cf. maculatus (Microprotopidae); Monocorophium insidiosum (Crawford, 1937) (Corophiidae); Nototropis massiliensis (Bellan-Santini, 1975) (Atylidae); Orchestia mediterranea A. Costa, 1853 (Talitridae); Orchestia montagui Audouin, 1856 (Talitridae); and Pleonexes helleri (Karaman, 1975) (Ampithoidae). New genera were registered: Apohyale Bousfield & Hendrycks, 2002; Monocorophium Bousfield & Hoover, 1997; Nototropis A. Costa, 1853; and Pleonexes Spence Bate, 1857. Seven species were represented by adult males and females, as well as juveniles. Two Orchestia species were identified by adult males. Individuals of species new to the Sea of Azov were found in the coastal zone in the following biotopes: supralittoral, macrophytes on the beach (O. mediterranea and O. montagui); detached macrophytes off the coast (A. crassipes); sand on the bottom at a depth of 0.2–1.5 m (A. sevastopoliensis and N. massiliensis); seagrass beds (M. insidiosum and Microprotopus cf. maculatus); and attached macrophytes on the bottom at a depth of 0.2–1.0 m (P. helleri). The occurrence of these species in the Sea of Azov may be associated with an increase in the salinity of its waters.

About finding Polydora websteri Hartman in Loosanoff & Engle, 1943 (Annelida: Spionidae) in the Sea of Azov

E. Lisitskaya — 2024-09-09

The research was carried out in 2023–2024 near the Kazantip Peninsula (the Sea of Azov). In this area, blisters were found in the shells of the mussel Mytilus galloprovincialis for the first time. The blisters occupied ⅕ to ⅓ of the shells area. The blisters contained boring polychaetes. Polychaetes were identified as Polydora websteri Hartman in Loosanoff & Engle, 1943 (Annelida: Spionidae). The results obtained must be taken into account when planning and organizing mussel farms in this area.

Cystoseira phytocenosis as a biological barrier for heavy metals and organochlorine compounds in the SPNA Cape Martyan marine area (the Black Sea): Review of the article

A. Ș. Bologa — 2024-09-09

The article by the Academician of the Russian Academy of Sciences V. Egorov et al. is reviewed. The paper provides the results of the study of the role Cystoseira species play as a biological barrier for the flow of pollutants, heavy metals and organochlorine compounds, in waters of the specially protected natural area “Cape Martyan.”

Growth of cultures of marine microalgae Porphyridium purpureum and Tetraselmis viridis on modified nutrient media

A. Borovkov — 2024-09-09

Marine species of microalgae are capable of synthesizing a wide range of biologically active substances and are currently considered as the most promising sources of such compounds. Nutrient media for cultivation of microalgae are mostly prepared based on natural or artificial seawater. Modifying the nutrient medium for cultivation of marine microalgae by replacing its natural seawater base with freshwater one seems promising. Unialgal cultures of the marine microalgae Porphyridium purpureum and Tetraselmis viridis were grown under conditions of replacing sterile seawater with freshwater, with sea salt added up to a concentration of 18 and 28 g·L⁻¹ for T. viridis and P. purpureum, respectively. Based on experimental data obtained, production characteristics of P. purpureum and T. viridis batch cultures were determined when grown on freshwater-based and seawater-based nutrient media. In general, a change in the density of P. purpureum and T. viridis cultures during batch cultivation both on freshwater and seawater had a unidirectional character (correlation coefficients in both cases were 0.99), and the water base of the nutrient medium had no significant effect on their growth rate. As shown experimentally, the biomass yield of P. purpureum and T. viridis using freshwater as a base of the nutrient medium was 3.2–3.4 g of dry weight per 1 L of the culture and generally corresponded to the similar parameter of cultures grown using seawater. Despite the fact that the mean growth rate of T. viridis cultured in freshwater did not differ significantly from the growth rate of the microalga cultured in seawater, higher mean rates of pigment synthesis and their total accumulation were observed in the culture grown in seawater. In the case of P. purpureum, the water base of the nutrient medium had no noticeable effect on B-phycoerythrin synthesis rate and content of this pigment in the culture and biomass of the microalga. The obtained results show that cultures of marine microalgae P. purpureum and T. viridis can be successfully grown without using natural seawater. It significantly reduces labor costs and biomass production costs; also, it expands geographical perspectives for their mass cultivation.

Color patterns of the thornback skate, Raja clavata Linnaeus, 1758, from the Sea of Marmara suggesting possible misidentifications of several rajids in the region

H. Kabasakal — 2024-09-09

Trawl surveys conducted in shelf waters of the northeastern Sea of Marmara revealed for the first time the occurrence of atypically colored thornback skates, Raja clavata Linnaeus, 1758 (Rajiformes: Rajidae), in the region. Since atypical coloring may lead to confusion and misidentification of R. clavata, an integrated approach of conventional alpha taxonomy and genetic studies is needed to resolve the taxonomic status of Raja species occurring in the Sea of Marmara. Accurate taxonomic resolution is the first step to properly differentiate the populations of the aforementioned species prior to performing further study and effective conservation.

The element contents in soft tissues and shells of the bivalve Anadara kagoshimensis (Tokunaga, 1906) from the Black Sea and Sea of Azov

L. Kapranova — 2024-09-09

In the ecosystems of the Black Sea and Sea of Azov, the invasive bivalve mollusc Anadara kagoshimensis is a poorly studied species. This clam is a valuable object in fishery and mariculture. Currently, there is little information about the element contents in soft tissues and shells of the mollusc living in these two seas. The aim of this work is comparative analysis of the elemental composition of A. kagoshimensis from the Black Sea and Sea of Azov. The elemental analysis was carried out using inductively coupled plasma mass spectrometry. The study presents data on the elemental contents in soft tissues and shells of this clam from the two seas. Noticeable differences in contents of elements were found between the sampling areas. These elements include: K, Rb, Cs, Ca, and Ba from the s-element family; the p-elements Al, Ga, Ge, P, As, Bi, and Br; the d-block elements Zn, V, Nb, Ta, Mo, Fe, Ir, and Au; and the f-block elements Pr and Nd. The elemental composition of A. kagoshimensis is determined not only by the composition of seawater, which contains mainly s-elements, but also by mollusc adaptation processes in which p- and d-elements are predominantly involved. In soft tissues of the clam from the Black Sea, concentrations of K, Rb, and Cs are significantly higher than in tissues of A. kagoshimensis from the Sea of Azov, while the concentration of K is one (the Sea of Azov) to two orders of magnitude (the Black Sea) higher in soft tissues than in shells. In shells of the clam inhabiting the Black Sea, Ca content is significantly higher, and these shells are stronger. Against the high calcium content, relatively low phosphorus content is noted in samples of soft tissues and shells from both seas. In soft tissues of A. kagoshimensis from the Black Sea, the contents of P, Al, Ga, Bi, and some heavy metals (Pb and Cd) are significantly higher. The contents of toxic elements in the mollusc from both seas do not exceed the maximum permissible levels. Zn and Mo are accumulated in soft tissues, and Fe is more concentrated in shells. In soft tissues of A. kagoshimensis from the Sea of Azov, Zn content is higher than in this clam from the Black Sea. Rare earth elements (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) are more concentrated in soft tissues of the mollusc from both seas than in shells, with Pr and Nd contents in specimens from the Sea of Azov being significantly higher than in those from the Black Sea. Anadara is capable of concentrating elements depending on their contents in the environment; therefore, the element accumulation in individuals of the same species is primarily a function of the biotope conditions.

A new species of arrow worms, Sagitta dimitryi sp. nov. (Chaetognatha, Sagittoidea), from the Sea of Okhotsk (Northwest Sakhalin)

A. Kasatkina — 2024-09-09

A new species of chaetognaths, Sagitta dimitryi sp. nov., was discovered in the waters of the Sea of Okhotsk, near the northwestern part of Sakhalin. The aim of this article is to describe the new species. A table of identification keys for species of the genus Sagitta is given, including Sagitta dimitryi sp. nov. The relationship of modern Sagitta with ancient Chaetognatha is discussed, including possible reasons for the evolution of the intestinal apparatus.

Bioluminescent bacteria of the Black Sea and Sea of Azov

A. Katsev — 2024-09-09

The aim of the present study was to isolate bioluminescent strains from the northern Black Sea and Sea of Azov, analyze their morphological and biochemical characteristics, and identify them based on 16S rRNA, recA, and gyrB gene sequences. Nine isolates were isolated from hydrobionts, and twelve, from seawater. Results of biochemical and molecular genetic identification revealed that isolated luminous strains represent the genera Vibrio, Aliivibrio, and Photobacterium. All five cultivated luminescent strains isolated from water and hydrobionts of the Sea of Azov belong to the species Photobacterium leiognathi. Cultivated luminous bacteria of the Black Sea are assigned to the genera Aliivibrio and Vibrio. The genus Aliivibrio is represented by two Aliivibrio fischeri strains related to various hydrobionts. Fourteen strains of the genus Vibrio belong to the species Vibrio campbellii, V. jasicida, V. harveyi, V. owensii, and V. aquamarinus sp. nov. Thus, it was shown that taxonomic composition of the cultivated luminescent bacteria differs greatly in the Black Sea and Sea of Azov.

Indices in the evaluation of the functional activity of blood cells of the bottlenose dolphin Tursiops truncatus (Montagu, 1821)

T. Seliverstova — 2024-09-09

The content of cationic protein in granulocytes of the bottlenose dolphin Tursiops truncatus (Montagu, 1821) was established by calculating the average cytochemical coefficient. Its shortcomings were substantiated in visually determining the intensity of staining of the product of a cytochemical reaction on blood products and distributing cells into groups according to the amount of protein they contain. To assess the activity of a substance in a cell, computer programs were applied, and a light microscope was used which allows to minimize errors in morphometric measurements of objects. Individual parameters were calculated for the degree of filling and intensity of staining of cationic protein in granulocytes in bottlenose dolphins with and without taking into account the protein content in the entire blood volume. Such indicators allow carrying out comparative age-related, intraspecific, and interspecific studies in animals. As established, the content of cationic protein in granulocytes can vary greatly in different individuals of bottlenose dolphins, and its amount changes slightly with age.

Current state of the population and features of the distribution of the soft-shell clams Mya arenaria Linnaeus, 1758 in the Kola Bay of the Barents Sea

O. Smolkova — 2024-09-09

The soft-shell clam Mya arenaria Linnaeus, 1758 is a boreal bivalve. The range of this species covers coastal waters of the Atlantic Ocean, the northeastern Pacific Ocean, and seas of the Arctic Ocean (the Barents and White seas). M. arenaria settlements can occupy vast areas along the coasts, where the molluscs form large aggregations and prevail in biomass among representatives of littoral macrozoobenthos. This species can withstand fluctuations in environmental factors and affect detritus formation and sedimentation. The mollusc juveniles inhabiting upper layers of the sediment are an important food object for seabirds and commercial fish species. High tolerance allows considering M. arenaria as an indicator of the effect of climate change on the Arctic ecosystem. Obtaining new data on peculiarities of the species biology is necessary to identify general patterns of development of benthic organisms under varying conditions of the marine environment, to understand adaptive characteristics of certain long-lived high-tolerant molluscs, and to assess the effect of environmental factors on them. The investigation of M. arenaria biology may be of practical significance as well: this species may become one of promising objects of mariculture in the Arctic region. The paper provides the results of a study of the current state of the soft-shell clam population and features of its distribution in the Kola Bay of the Barents Sea. Material was sampled during MMBI RAS coastal expedition in 2021. Quantitative characteristics and size and age structure of the mollusc settlements were analyzed. M. arenaria aggregations were recorded in the intertidal zone of the western and eastern shores of the middle and southern bay areas. The mollusc settlements in the intertidal zone off the Elovyi Cape (the Tuloma River mouth) were found for the first time during the entire period of research in the Kola Bay (1921–2021). The highest abundance was registered in the Khlebnaya Bay (67.1 ind.·m⁻²), and the lowest one was noted in the Belokamennaya Bay (5.0 ind.·m⁻²). There were no abundant aggregations in the intertidal zone off the cape Abram-mys and in the Vayenga Bay. Settlements in the Kola Bay are represented by the soft-shell clams aged 4 to 14 years, with the size varying 17.5 to 91.2 mm. Apparently, M. arenaria distribution and quantitative and morphometric characters of its settlements are related to hydrological features of the bay (the intensity of movement of water masses in small bights and cyclonic movement of water masses in the southern bay area). An increase in the mollusc abundance and an expansion of its range may be interpreted as a response to climate change in the Arctic region and an indicator of reduction of anthropogenic load on coastal communities throughout the Kola Bay.

Species composition, abundance, and biomass of phytoplankton in the Kerch Strait in 2009–2019

O. Yasakova — 2024-09-09

The results of studies of planktonic algae developing in the Kerch Strait in various seasons of 2009–2019 are presented. Phytoplankton included 114 species and several taxa identified down to the genus level covering 11 classes of algae, inter alia 64 Dinophyceae species and 32 Bacillariophyceae species. Mean values of abundance and biomass were 140 thousand cells·L⁻¹ and 0.386 g·m⁻³, respectively. Cyanophyceae prevailed accounting for 44% of the total phytoplankton abundance. Bacillariophyceae and Dinophyceae formed a significant part of the total phytoplankton abundance (19 and 18%) and biomass (62 and 35%). Cryptophyceae, Coccolithophyceae, and Chlorophyceae amounted to 18% of the total phytoplankton abundance. In spring, small-cell diatoms Skeletonema costatum and Cyclotella caspia dominated. In summer, large- and small-cell species of Bacillariophyceae and Dinophyceae prevailed, along with a Coccolithophyceae representative Emiliania huxleyi. In autumn, species of Cyanophyceae (Planktolyngbya limnetica), Cryptophyceae (Plagioselmis), and Chlorophyceae (Binuclearia and Nannochloris) were the most abundant ones. Bacillariophyceae (Pseudosolenia calcar-avis) and Dinophyceae (Prorocentrum, Protoperidinium, and Ceratium species) formed the major part of the phytoplankton biomass.