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Rutilus rutilus (Linnaeus, 1758) [N]—Roach Taxonomy. Original description: Cyprinus rutilus Linnaeus, 1758: 324 [European lakes; possible syntypes: LS 44 (1, right half-skin)].— Afghanistan synonyms: Leuciscus rutilus (Linnaeus, 1758).—Revisions: Berg (1949: 493).—Illustration: Berg (1949: 494, fig. 291). Status in Afghanistan. First record from Afghanistan by Amanov (1974); then Moravec and Amin (1978) and confirmed by Coad (1981: 11; 2014: 318).—Afghanistan materials: None. Distribution and habitat. Distribution in Afghanistan: Termez, Afghan-Uzbekistan border, Khanabat River.— General distribution: Europe and western Asia; widely introduced elsewhere.—Habitat: This species occurs in a wide variety of habitats, mainly in lowland areas. Most are abundant in nutrient-rich lakes, large to medium-sized rivers, and backwaters. Known also from small lowland streams and brackish coastal lagoons. Spawns among dense submerged vegetation in backwaters or lakes, flooded meadows, or shallow, fast-flowing river habitats on a plant or gravel bottom. Freshwater. Economic importance. Commercially important. Conservation. Conservation status in Afghanistan: Unknown.—IUCN: LC (Freyhof & Kottelat 2008f).—Threats: No major threats known.—Low sensitivity to human activities.—Not considered as a keystone species.— Decline status: Unknown.—Low priority for conservation action., Published as part of Çiçek, Erdoğan, Fricke, Ronald, Eagderi, Soheil, Sungur, Sevil, Coad, Brian W & Hamdard, Mohammad Hamid, 2023, Fishes of Afghanistan; a revised and updated annotated checklist, pp. 1-69 in Zootaxa 5305 (1) on pages 36-37, DOI: 10.11646/zootaxa.5305.1.1, http://zenodo.org/record/8048564, {"references":["Linnaeus, C. (1758) Systema Naturae. Vol. 1. Ed. X. [Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata]. Impensis Direct. Laurentii Salvii, Holmiae, ii + 824 pp.","Berg, L. S. (1949) s. n. In: Ryby presnych vod SSSR i sopredelnych stan. [Freshwater fishes of the U. S. S. R. and adjacent countries]. Vol. 2. 4 th Edition. Opredeliteli po faune SSSR. [Guide to the Fauna of the U. S. S. R.], Moskva. Freshwater fishes of the U. S. S. R. and adjacent countries No. 29. Russian Academy of Sciences, USSR, Moskva, pp. 467 - 925. [in Russian, English translation appeared in Israel Program of Scientific Translation, Jerusalem, 1964, 496 pp.]","Amanov, A. A. (1974) Ecology of the Bukhara roach [Rutilus rutilus bucharensis (Nikolskij)] of the Uch-Kyzyl Reservoir in the Surkhan Darya River basin. Journal of Ichthyology, 14 (1), 40 - 46.","Moravec, F. & Amin, A. (1978) Some helminth parasites excluding Monogenea from fishes of Afghanistan. Acta Sci Nat Brun, 12, 1 - 45.","Coad, B. W. (1981) Fishes of Afghanistan, an annoted checklist. National Museum of Canada Publications in Zoology, 14, i - v + 1 - 26.","Coad, B. W. (2014) Fishes of Afghanistan. Pensoft Publishers, Sofia-Moscow. 393 pp.","Freyhof, J. & Kottelat, M. (2008 f) Rutilus rutilus. The IUCN Red List of Threatened Species, 2008, e. T 19787 A 9014741. https: // doi. org / 10.2305 / IUCN. UK. 2008. RLTS. T 19787 A 9014741. en"]}

Interspecific hybridization in the Cyprinidae family has been recorded worldwide, with Abramis brama (bream) and Rutilus rutilus (roach) as one of the often-reported hybridizing pairs. The only account of such an event in Bosnia and Herzegovina has been in Modrac Reservoir. Using morphological and molecular markers, the presence of hybrids was surveyed, the hybridization direction was determined and the hybrid group structure in this ecosystem was evaluated. Our findings confirmed unhindered natural hybridization between roach and bream in Modrac Reservoir. Over 50% of the hybrid specimens were classified as F2 hybrids by the NewHybrids software, while the rest were categorized as pure parental form, making it the first such finding in Europe. The analysis of mitochondrial cytochrome b showed that 90% of hybrid individuals were of bream maternal origin. The hybrid group expressed higher mean values of observed heterozygosity and gene diversity than both parental species. Signs of introgressive hybridization between parental species were detected. The hybrid zone of Modrac Reservoir appears to follow the intermediate or “flat” hybrid model based on the balanced distribution of parental and hybrid genotypes. Further investigation is needed to elucidate the factors that enable the survival and mating success of post-F1 individuals.

The offshore zone of the western coast of the Caspian Sea is one of the most highly productive. Of the 63 species of fish that live in the Caspian Sea, 34 species are found on the Krainovsky coast, 42 % of which are carp. The most numerous is the roach Rutilus rutilus caspicus (Jakowlev, 1870), which makes up 50–86 % of the number of semi-passerine and river fish. The article presents the results of studies of the peculiarities of the biology of the roach Rutilus rutilus caspicus of the Krainovsky coast of the Caspian Sea. The roach is noted in the catches constantly. Her age in the networks ranges from 2 to 10 years. The share of 3-5-year-olds accounts for 81 %. Females in catches make up 66 %, males - 34 %. The parameters of the Bertalanfi equation are characterized by the following values: L =38.8 cm, K = 0.12, t° = -2.67. The fecundity of the roach on average is 30.2 thousand eggs and tends to increase with increasing length and weight of the fish. As the roach grows, the composition of its food changes significantly. The maximum fed roach length from 10 to 20 cm.

The objective is to perform a comparative evaluation of the pancreatic hydrolysates prepared from fish and squid to determine the optimal culture medium for Listeria monocytogenes.Materials and methods. The following raw materials were used in the study: Pacific Herring (Clupea pallasii), Alaska Pollock (Gadus chalcogrammus), Common Roach (Rutilus rutilus lacustris), European Squid (Loligo vulgaris). The raw materials were subjected to enzymatic hydrolysis using the pancreas (according to Hottinger). A study of the physicochemical properties of pancreatic hydrolysates (content of free amino nitrogen (FAN), acidity of fish hydrolysates, the amino acid composition) was carried out.. The specific activity of nutrient media during the cultivation of the test strain L. monocytogenes 766 was assessed by a complex of microbiological methods.Results and discussion. The highest content of FAN at the end of enzymatic hydrolysis was observed in the pancreatic hydrolysate of the common roach (6%), the acidity of the hydrolysate remained stable from 6th to 13th day of the hydrolysis process (pH 7.2). Pancreatic hydrolysate of the common roach contained a number of amino acids that are most essential for the growth of Listeria. An assessment of the biological properties of nutrient media prepared on the basis of the obtained hydrolysates demonstrated that the best results in terms of sensitivity and germination of L. monocytogenes 766 showed a nutrient medium based on the pancreatic hydrolysate of the common roach. During the cultivation of L. monocytogenes 766 the test strain retained its morphological and cultural properties and did not show signs of dissociation.Conclusion. The research results have shown that the pancreatic hydrolysate of the common roach is a promising protein basis for the construction of an experimental environment for listeria.

Purpose The present study investigates the fish parasite fauna from Lake Tollense, Mecklenburg-Western Pomerania, Germany. Methods A total of 117 perch (Perca fluviatilis), bream (Abramis brama) and roach (Rutilus rutilus) were sampled for parasites during 2018 and 2019 from Lake Tollense and compared with earlier data from Lake Malchin and Lake Hohen Sprenz in 2011 and 2014, respectively. Parasites were identified based on morphological and molecular characters. Results A total of 32 parasite species were isolated from fishes of Lake Tollense, predominated by digeneans. Diplostomum baeri was found only in perch while D. spathacaeum was isolated from bream and roach. Parasite comparison of similar hosts between lakes revealed highly abundant Ichthyocotylurus spp. in perch and bream of Lake Malchin while Aspidogaster limacoides was most common in roach from Lake Tollense. Diversity indices of roach showed significant variation between localities. However, NMDS graph revealed separation of the three freshwater habitats based on the parasite fauna of perch, bream and roach. Conclusion Based on the multivariate statistical analysis, the three natural inland water bodies could be distinguished based on the parasite communities of perch, bream and roach. The potential to utilise fish parasites as biological indicators in freshwater ecosystem is discussed.

The results of a comparative analysis of the frequency and diversity of axial skeletal anomalies in common roach Rutilus rutilus from four parts of the Angara River with different levels of technogenic load are given. A total of ten types of anomalies have been revealed; two of them occur everywhere. The proportion of adult individuals with anomalies tends to increase during their early ontogenesis as the quality of surface waters degrades. The maximum frequency and diversity of phenodeviants have been recorded in areas exposed to chronic technogenic impact (water pollution class 2–3).

Inroduction. Changes in the species composition and population size of freshwater fihes are determined by deformations of the habitat in Ukraine and are characterized by a pronounced negative dynamics. Deformation of ichthyofauna is caused by extinction of a number of aboriginal fihes and emergence of alien species.Aim. To establish the current species composition and relative population size of fih species in the Oster River and the dynamics of these characteristics over a 50-yearlong period in the context of negative transformations of the ichthyofauna of the rivers of Ukraine.Results. Comparative study of the species composition and relative population size of fih species in the fih catches by small-river fihing gear in the Oster river was conducted during the period since 1971-72 till 2019. During this time considerable changes in species composition took place. The following species disappeared from the catches: Leuciscus leuciscus, Leuciscus idus, Chondrostoma nasus, Carassius carassius, Blicca bojerkna and Neogobius flviatilis, they were replaced by three invasion species (Percottus glenni, Pseudorasbora parva, Proterorhinus marmoratus). The changes in the dominant species took place, thus, in the Oster ichthyocene the species with the short life cycle started to prevail, the share of invasion species increased from 1.4 to 37%, and the share of initial marine fih among them is very low. The comparison with the river systems of the Stugna and the Lower Dnipro represents the fact that the mentioned negative tendencies are common for the whole Dnipro system, however the situation in the Lower Dnipro must be considered less critical than in the Oster and the Stugna rivers. The fact that the catches of industrial fih decreased more than 10 times in the Desna river during this period of time gives the reason to consider that the dramatic reduction of the absolute number of their populations occurred in the Oster river as well. That is why even relatively safe species (Abramis brama, Rutilus ritilus, Scardinius erythrophthalmus, Esox lucius, Perca flviatilis, Alburnus alburnus, Squalius cephalus) are in critical situation in this transformed river system.Сonclusions. In the ichthyocene of the Oster River over a 50-year period there have been signifiant changes in species composition, relative and absolute population numbers associated with the extinction and reduction of population sizes of rheophilic species and fih that are adapted to life in the flodplain. The modern Oster River is dominated by invasive and short-cycle species. The obtained tendencies in the dynamics of the ichthyofauna of the Oster River are similar to the nature of changes in other river systems of Ukraine, although they occur at a faster pace, which is characteristic of the smallest plain rivers.

The paper describes the remote effects of magnetic field variations with intensity of 100, 300 and 500 nTl and duration of 6 h on embryos of roach Rutilus rutilus. The exposure lasted from the 2nd to the 7th or from the 33rd to the 38th hours post fertilization. The impact of the investigated factors led to changes in the body length-weight parameters and redistribution of the vertebrae between the parts of the spine in underyearlings. Analysis of variance revealed a significant effect of the exposure time and the interaction of factors of the intensity of magnetic fluctuations, as well as different exposure times on the studied parameters

The results of the study of the Lake Maslozero ecosystem (the White Sea basin) are reported. The lake is small, deep, and poorly lotic. Its hydrochemical and hydrobiological parameters were studied. The quantitative and structural characteristics of the state of zooplankton and macrozoobenthos in the lake are presented for the first time. The lake is an oligo-mesotrophic water body, as indicated by the nutrient content scale. The lake is inhabited by 14 fish species of 11 families. The perch Perca fluviatilis, the whitefish Coregonus lavaretus, the pike Esox lucius, the roach Rutilus rutilus, and the introduced smelt Osmerus eperlanus are the most abundant. The work on the introduction of smelt into Lake Maslozero is evaluated. The smelt in the lake has naturalized, is successfully reproducing, and has become abundant. Its growth rate is identical to that of the smelt from its parental water body, Lake Ladoga. The food ration of predatory fish (pike, burbot, perch, and char) is dominated by smelt as the most abundant and accessible food item available all year round. The lake is used by the local population for economic purposes, recreation, amateur fishing, and fish culture.

Italy hosts a large number of endemic freshwater fish species due to complex geological events which promoted genetic differentiation and allopatric speciation. Among them, the South European roach Sarmarutilus rubilio inhabits various freshwater environments in three different ichthyogeographic districts. We investigated the genetic diversity of S. rubilio using two different mitochondrial markers (COI and CR), aiming to define its relationship with other similar taxa from the Balkan area and, from a phylogeographic perspective, test the effects of past hydrogeological dynamics of Italian river basins on its genetic structure and demographic history. Our analysis highlighted a marked genetic divergence between S. rubilio and all other roach species and, among Italian samples, revealed the existence of three deeply divergent geographic haplogroups, named A, B and C. Haplogroup C likely corresponds to a new putative cryptic species and is located at the northern border of the South European roach range; haplogroup B is restricted to Southern Italy; and haplogroup A is widespread across the entire range and in some sites it is in co-occurrence with C or B. Their origin is probably related to the tectonic uplifting of the Apuan Alps in the north and of the Colli Albani Volcano in the south during the Pleistocene, which promoted isolation and vicariance followed by secondary contacts.

The long-term (postponed) consequences of the separate and combined effects of Cu2+ ions (0.001, 0.01, and 0.1 mg/L) and a low-frequency electromagnetic field (50 Hz, 10 μT) on roach Rutilus rutilus (L.) embryos have been studied, bringing to light the exposure to these factors to changes in the size and weight parameters, the activity of glycosidases (sucrase, maltase, and amylolytic activity), and the kinetic characteristics of maltose hydrolysis in the intestines of underyearlings exposed at a stage of embryos. Increased body weight, body length, and intestine length are revealed in fish exposed to the electromagnetic field and the combined treatment of an electromagnetic field and Cu2+ ions. Compared with the control, the activities of sucrase and maltase are higher, while the amylolytic activity is lower in roach exposed to different combinations of the factors. The electromagnetic field compensates the inhibitory influence of Cu2+ on amylolytic and maltase activity. The values ​​of the Michaelis constant (Km) of maltose hydrolysis in the intestines of underyearlings exposed to these impacts exceed those in the control. This result indicates a decrease in the enzyme affinity for the substrate, probably caused by the separate and combined influence of Cu2+ and the electromagnetic field on the roach during early development. These results are important for assessing environmental risks in industrial areas.

The data on the catch, age composition and growth of the roach Rutilus rutilus L. in commercial herd in the Middle Ob basin (in the Tomsk region) are presented. It is shown that the catches of the roach in the middle of the 20th century were 2098 tons per year. In the second half of the 1960s, they fell sharply by more than two times. It was caused by a decrease in the areas of effective spawning due to the reduction of runoff in the Ob during spring floods as a result of the regulation of the level regime by the dam of the Novosibirsk hydroelectric power station. After that, the catch of roach remained at about 1013 tons per year until the beginning of economic reforms in the country, when the catch of this species became unprofitable, as a result of which catches decreased to an average of 436 tons per year. Currently, the basis of commercial catches is made up of roach with a commercial length of 140 to 210 mm and a weight of 50 to 150 g at the age of 2+...5+. It is noted, compared with the 1970–1980s, there is a shift in the age series towards an increase in the value of older age groups, which may indicate underutilization of the stock of the roach. The statistically significant positive relationship between catches of roach and the average duration of flooding of the floodplain in the years of the occurrence of generations that form the basis of catches was revealed. Prolonged floods also provide better conditions for fish feeding (a statistically significant positive relationship between the mass of fish of the same age and the duration of flooding of the floodplain is shown). Thus, the hydrological regime in the spring has a decisive influence on the state of the stocks of roach in the Middle Ob.

Lice (Anoplura) were studied in 2015–2018 in the middle taiga of West Siberia in the territory of the Middle Ob region (Khanty-Mansi Autonomous Okrug–Yugra). Lice were found on 15 species of small mammals, of which the most significant hosts were Alexandromys oeconomus, Microtus rossiaemeridionalis, M. agrestis, Myodes glareolus, and M. rutilus. The louse Hoplopleura acanthopus had the widest host range and was also dominant among all the louse species found on small mammals. The peaks of louse abundance coincided with those of host reproductive activity in late spring and early autumn. In the most common host A. oeconomus, the highest degree of infestation (mainly with H. acanthopus) was recorded in adult males; the corresponding indices were significantly lower in adult females and especially low in young mammals. The population structure of H. acanthopus showed prevalence of females (about 50%) in comparison with males and larvae. Co-parasitism of lice was especially pronounced on adult host specimens. The lice Hoplopleura edentula, Hoplopleura longula, and Polyplax hannswrangeli were recorded for the first time from the studied territory.

In the diagnosis of stressful conditions in humans and other animals, ionic indicators remain practically unused. In this work, we studied the changes in the concentrations of sodium ions in the blood plasma of freshwater fish under stress caused by stressors of different quality and quantity. Most of the experiments were carried out on adult bream (Abramis brama L) from the Rybinsk Reservoir. Separate experiments were duplicated on adult individuals of roach (Rutilus rutilus L.), pike (Esox lucius L.), and blue bream (Abramis ballerus L.). The concentration of cations in the blood plasma was determined using a Flapho-4 flame photometer. Under the action of mild and short-term stressors of different qualities, the sodium concentration in the internal environment altered toward an increase in concentration gradients on the cell membrane (eustress or physiological stress). Hypernatremia was approximately 10%. Under the action of strong and/or prolonged stressors of different strength, the sodium concentration in the internal environment changed toward a decrease in concentration gradients on the cell membrane (distress or pathological stress). Hyponatremia was 50% in the conditions of acute lethal stress, 20% in subacute lethal stress, 10% or more in chronic lethal stress. During strong acute reversible stress, hyponatremia could reach 30%. Analysis of the material on mammals allowed us to conclude that the adaptation mechanisms in fish and higher vertebrates are similar. In this work, for the first time, the state of the system of electrolyte balance of animals under stress was analyzed from the standpoint of the leading role of ionic concentration gradients on the cell membrane (mainly sodium) in the energetics (level of disequilibrium) of the organism. We propose a concept that in normal and extreme conditions fish use two different defense reactions (or adaptation strategies): active and passive, consisting, respectively, in increasing or decreasing the level of disequilibrium (energy) in the organism. The hyponatremia recorded by numerous authors, which accompanies diseases in humans, is evidently a nonspecific reaction of the organism and serves as an indicator of reduced energy of the organism. It is suggested that the sodium level in the internal environment of the organism be used for diagnosing the stress state of animals.

The in vitro effects of amorphous phenol and its liquid fractions formed 12 months after production were studied in seven freshwater bony fish species: the common carp Cyprinus carpio L., bream Abramis brama (L.), silver bream Blicca bjoerkna (L.), roach Rutilus rutilus (L.), perch Perca fluviatilis L., and sander Zander lucioperca (L.). The study revealed that the effects of amorphous phenol and its liquid fractions are species-specific and depend on the concentration of phenol and localization of peptidases (intestine mucosa or intestinal cavity in case of chyme). The specific features of the effect of amorphous phenol differ considerably from the effect of crystalline phenol.

The mass of pharyngeal teeth (pharyngeal jaws with teeth located on them) and its proportion of the total body mass of the roach Rutilus rutilus (Linnaeus, 1758) with different feed types in the Rybinsk Reservoir have been analyzed. It is ascertained that the proportion of pharyngeal tooth mass tends to increase significantly as the fish body length increases from 170 to 200 mm, body mass from 90 to 200 g, and the age from 5 to 7 years. This parameter for the analyzed specimens does not depend on the number of teeth on the pharyngeal jaws. The absolute and relative masses of pharyngeal teeth are not associated with genetic traits such as the number of vertebrae in the vertebral column and its sections. However, fish with a high relative mass of pharyngeal teeth are characterized by higher phenetic diversity in the number of phenotypes in the vertebral column.

We investigated the distribution of mitochondrial lineages of two species—the common roach Rutilus rutilus and Ponto-Caspian roach R. lacustris—in the broadest zone of their secondary contact, the Volga basin. For the purpose of species identification, we applied the approach of multiplex PCR based on species-specific divergences in sequences of the first subunit of cytochrome oxidase (COI) of mtDNA. A total of 1120 samples from 82 localities are analyzed. The distribution of certain mitochondrial lineages and their sympatric co-occurrence clarified for the Volga basin. Our study shows that R. rutilus is significantly predominant in the Upper Volga, while the Middle and Lower Volga is dominated by R. lacustris. The various hypotheses of formation of the broad spatial pattern of secondary contact are discussed.

The absence of magnetic fields can affect fish embryogenesis. The influence of hypomagnetic field on the survival of roach (Rutilus rutilus) embryos was estimated. Delayed consequences of R. rutilus embryos and prelarvae exposure to these magnetic conditions were also studied. Hypomagnetic field during embryogenesis led to an increased mortality of embryos. The juveniles developed from the exposed embryos were characterised by reduced vertebral phenotypic diversity. The influence of hypomagnetic field on roach prelarvae led to changes in the size–mass indices of juvenile fish. Present results differ from those that were previously obtained in experiments with simulated geomagnetic storms and artificial low-frequency magnetic fields and emphasise the importance of the magnetic environment for the fish embryogenesis. Possible mechanisms of the described effects are discussed.

The aim of this study was to determine the levels of Na, K, Ca, Mg, Fe, Zn, Cu, Pb and Cd in the muscle, liver and gills of roach (Rutilus rutilus) and perch (Perca fluviatilis) from three polymictic and eutrophic lakes in poor ecological condition in north-western Poland. Metals in the waters of the lakes, as well as in the muscle, gills and livers of fish, were determined by atomic absorption. Oxygen deficits in summer and high concentrations of Cd and Pb were responsible for the low water quality of the lakes studied. Perch and roach showed a potential to accumulate metals from the water (bioconcentration factor >1). The lowest concentrations of Na, Fe, Zn, Cu, Pb and Cd were found in the fish muscle. The highest concentrations of Cd and Pb were recorded in the liver of both species. Differences in metal concentration between the species were mainly due to significantly higher levels of Fe, Cu and Zn in the muscle of the roach than in the perch (p

The trace elements (TEs) in aquatic environments due to anthropogenic activities are readily available to aquatic organisms. There are 153 fish species inhabiting the Caspian Sea. However, little is known about TE (TE) concentrations in these species. In this study, we investigated the effects of TEs levels in the brain of some bony fish species inhabiting the Caspian basin. Totally, 405 fish from nine species with different feeding behaviors including Leuciscus aspius (n = 20) and Perca fluviatilis (n = 37) as piscivores, Rutilus kutum (n = 27) and Rutilus caspius (n = 71) as carnivores, Vimba persa (n = 56), Ponticola caspia (n = 25) and Tinca tinca (n = 31) as mollusivores, and Alburnus chalcoides (n = 77) and Alosa braschnikowi (n = 61) as zooplanktivores were collected from the southwest of the Caspian Sea basin from September 2017 to June 2018. The ICP-OES was used to measure TEs in the brain tissue of fish. The variability of TEs concentrations in the brain tissues of these fishes by principal component analysis (PCA) was decreased to 63.59% and 17.68% for PC1 and PC2, respectively, exhibiting that 81.27% of the total variability is associated with K, Mg, P, S, Zn, and Al. The two-dimensional diagrams showed the weight of each component in PCA. The PC1 was mostly influenced by P, Mg, K, and Zn, while the greatest value in PC2 belonged to Al. Furthermore, the entire number of elements determined in this study was found to be a suitable indicator for the distinction between fish species based on their feeding items.

The number of pores in the seismosensory canals of several paired integumentary head bones was counted for specimens of the roach and European perch caught in 15 small ponds in the central–eastern part of the Udmurt Republic, Russia. Three indices of fluctuating asymmetry were calculated on the dataset obtained, and a statistical analysis of the relationships of these indicators with the average (over several years) mineralization of water bodies for different periods of the growing season and with their variation coefficients has been carried out. In the roach, the average proportion of asymmetric variants of the studied traits was significantly associated with seasonal variability of mineralization values only, while close and statistically significant relationships between this indicator and the average mineralization values ​​in individual periods of the growing season have been found in the European perch. Similarly, another indicator of the roach, the variance of fluctuating asymmetries of the total values ​​of paired meristic signs of the cranial seismosensory system, was similarly associated with these values. Possible mechanisms of the influence of the mineralization factor on the degree of asymmetric manifestation of the studied signs are discussed, taking into account the features of their gradual formation in the early ontogenesis of the two fish species. As a result, some limitations on the adequate use of these indicators in the bioindication of anthropogenic pollution of freshwater by dissolved inorganic substances are considered.

In the present study, we assembled and annotated the complete mitochondrial genome of Chroogomphus rutilus. The complete mitochondrial genome of C. rutilus was composed of circular DNA molecules, with a size of 37,508 bp. The GC content of the C. rutilus mitogenome was 22.82%. A total of 18 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, and 24 transfer RNA (tRNA) genes were detected in the C. rutilus mitogenome. Phylogenetic analysis based on combined mitochondrial gene dataset indicated that the C. rutilus exhibited a close relationship with species from the genus Rhizopogon. This study served as the first report on the complete mitochondrial genome from the family Gomphidiaceae, which will promote the understanding of phylogeny, evolution, and taxonomy of this important fungal species.

A new myxobolid species, Myxobolus zaikae n. sp., was found in the connective tissue near the kidney and liver blood vessels of the common roach Rutilus rutilus, while fish myxosporean fauna were being investigated in Lake Baikal, Russia. The parasites were studied on the basis of spore morphology as well as with histological and molecular methods. Mature spores of M. zaikae n. sp. are round or ellipsoidal in the frontal view and lemon-shaped in the lateral view, measuring 11.37 ± 0.11 µm (10.2-14.0 µm) in length, 10.29 ± 0.10 µm (9.6-11.0 µm) in width, and 6.3 ± 0.08 µm (5.8-7.1 µm) in thickness (mean ± SD; n = 50). Polar capsules are equal and pyriform, measuring 4.5 ± 0.07 µm (3.4-5.2 µm) in length and 2.9 ± 0.03 µm (2.6-3.3 µm) in width. Polar capsules contained polar filaments coiled with 5 to 6 turns. Phylogenetic analysis showed that this newly described species clusters with other myxobolid species infecting the connective tissue of different organs from Palearctic cyprinid fish.

The genus Rutilus is widespread in the western and central Palearctic region. In the Caspian Sea, the taxonomic status of different populations of Rutilus lacustris has been debated due to different sub-specific names attributed to each population. We genotyped 7,984 single nucleotide polymorphisms and sequenced the mitochondrial cytochrome C oxidase subunit I gene of 37 R. lacustris and Rutilus frisii from the southeast and southwest Caspian Sea and the Aras River in the Kura River drainage. We analysed data using clustering, Bayes factor delimitation, introgression, assessment of migration rate, and phylogenetic analyses. The results showed that the southeast and southwest Caspian Sea populations of R. lacustris were closely related, but highly differentiated from R. lacustris in the Aras River. The Bayes factor delimitation test supported the existence of three populations of R. lacustris in the studied area. Three hybrid individuals with mtDNA from Abramis brama or R. frisii and nuclear DNA from R. lacustris were detected. To protect R. lacustris in the southern Caspian Sea, we propose that the Aras River and sea-run R. lacustris be treated as two separate conservation units and the southern Caspian Sea R. lacustris populations should be viewed as two potentially separate management units.

In most cases in natural environments, hybrids of roach Rutilus rutilus L. and bream Abramis brama L. possess mitochondrial DNA of bream. Presumably, the genetic basis for unidirectional hybridization of roach and bream is the high level of divergence in the genes of the mitochondrial electron transport chain (cytochrome b and cytochrome c oxidase subunits I, III). Disruption of the interaction of the products of these genes leads to nuclear-cytoplasmic incompatibility of alien genomes, what is shown in a decrease of viability and developmental abnormalities in hybrids. In the present work we studied the viability and morphology of hybrid underyearlings obtained by crossing of hybrid females of first generation (RA and AR) with males of roach R. rutilus and bream A. brama. The method of genotyping (ITS1 ribosomal DNA, cytochrome b mtDNA) and comparative analysis of the complex of 23 plastic and meristic characteristics of backcrossed hybrids are used. All progenies showed an increase in morphological variability compared to parental species and F1 hybrids. In progenies with introgression of mtDNA, a violation of associations between traits and the formation of transgressive phenotypes that go beyond the parental populations were found. In RAA backcrosses (combining mtDNA of R. rutilus and nuclear genome of A. brama) a decrease in viability with impaired recovery of external traits of bream was found. Conversely, ARR backcrosses (combining mtDNA of A. brama and the nuclear genome of R. rutilus) have a high viability and completely restore the morphotype of roach, which indicates the stable development of hybrids when they include alien genetic material. The differences in viability and morphology between backcrossed hybrids with the mtDNA of R. rutilus and A. brama evidence varying degrees of nuclear-cytoplasmic compatibility of the genomes of roach and bream. The complete interaction between mitochondrial and nuclear DNA from different species (wild-type-like) happens in direction of introgression mtDNA of A. brama, the less polymorphic of the two parental genomes. In the direction of introgression of highly polymorphic mtDNA of R. rutilus the formation of a reproductive barrier occurs. Our results show that the main reason for the asymmetry of hybridization of R. rutilus and A. brama is unequal rates of mitochondrial evolution and the priority of the introgression of mtDNA belongs a species with a lower rate of changes in mtDNA.

The seasonal dynamics of the motivational component of rheoreaction (ratio of rheoreaction types) has been studied in roach Rutilus rutilus L. inhabiting the Rybinsk Reservoir, Russia. The circular hydrodynamic tank with limnozone is used. The change in the ratio of rheoreaction types in nonmigratory mature roach may adequately reflect its behavior in the reservoir. The fish sex, stage of gonad maturation, and water temperature had a weak effect on the rheoreaction types and stability of their manifestation.

Purpose. To investigate changes in the biochemical parameters of roach as a species response to the effects of anthropogenic pollution, which is necessary for further biomarking of the aquatic environment. Methodology. Fish were caught using hook and line fishing gears. Following biochemical parameters of roach were determined: glycogen and lipid contents, activities of lactate dehydrognase, succinate dehydrogenase, ATPase and alkaline phosphatase. Findings. Changes in some biochemical parameters of roach under the effect of anthropogenic pollution have been found. A lower content of glycogen and lipids (by 68.65 and 16.12%) was detected in fish from a polluted water body (Lake Kyrylivske) compared to fish from the conditional control (Lake Babyne). The active use of reserved lipids and glycogen emphasizes the general deterioration of ecological conditions in the Lake Kyrylivske. A higher LDH activity in liver and gill tissues (by 25 and 48%) relative to control was found. In contrast, a lower LDH activity (by 11 and 16%) in all studied tissues (muscles, liver and gills) of roach from the polluted water body was detected. Under conditions of pollution of the water body with toxicants of various chemical nature, aerobic redox processes in roach body are intensified as a result of counteracting a potentially aggressive environment. This is confirmed by a higher LDH activity in liver and gill tissues. According to the results of study, a higher alkaline phosphatase activity was also detected in fish from the Lake Kyrylivske (by 39.9 and 24.6%) compared to the control. This indicates an increase in phosphorylation in these tissues, the process of which is aimed at neutralization and excretion of toxic compounds from the body after their detoxification. The differences between the studied groups of fish in biochemical parameters prove that they live in significantly different ecological and toxicological conditions. Originality. For the first time, the results of changes in biochemical markers of roach enzyme activity from some water body of Kyiv, which differ in the level of anthropogenic pollution, are presented. Practical value. The obtained results of the physiological state of roach can be used as a criterion for assessing the ecological status of individual waterbodies, in particular those that are located in urban areas.

Climate warming and the introduction of a new mass species of clam Dreissena bugensis can potentially lead to changes in the reproductive capacity of benthic fish species living in the upper Volga reservoirs. The age of puberty, the structure of the spawning stock, and fecundity are the main indicators of reproduction that determine, together with indicators such as the survival of young fish and the degree of fishing load, the relative number of species in the ichthyofauna. The purpose of this work was to study the size and age of the onset of puberty and the dynamics of fecundity of roach Rutilus rutilus in the Volga ples of the Rybinsk reservoir. Determination of individual absolute fecundity was performed by counting eggs in fresh gonads, without the use of fixation. The age of fish was determined by scales, and vertebrae and operculum were used as additional recording structures. As a result, it is shown that the beginning of sexual maturation of female roach occurs when reaching the age of 3+ and a length of more than 9 cm. Late maturing females were 4+ years old and over 18 cm long. The beginning of sexual maturation of males could not be determined. The smallest males in the catches, 7–8 cm long, were all sexually Mature. The maximum age of fish reached 12+ years with a length of no more than 32 cm. Individual absolute fertility ranged from 1,75 to 178,46 thousand eggs. The value of relative fertility ranged from 79 to 308, with an average of 171 eggs/g. The result concluded that high absolute and relative fecundity of roach and dynamic changes of fertility in terms of increase in average water temperature and absolute improvement of fodder after the invasion of Dreissena bugensis, may indicate the attainment of specific limit reproductive capacity of this species.

The food composition of sander Sander lucioperca in the Rybinsk Reservoir was studied during the period of regional climate warming and along with significant fluctuations in the harvests of the southern invasive fish species, tyulka Clupeonella cultriventris. In the period of the relatively low abundance of tyulka (2007–2014) compared to the year following its mass outbreak (2016), the proportion of this species in zander diet was two-fold less (28.3 versus 60.7% of the number of prey consumed). In 2007−2016 tyulka took the first place in the food of sander: its share in the diet in riverbed and floodplain sections of the reservoir was 39.5 and 33.9%, respectively. In 2010 the period of intensive feeding of sander lasted until December inclusive. Compared to the period of the climatic norm, in the younger age groups of sander (3 + −6 +) the dates and places of feeding have changed: they fed on biotopes of open and protected littoral, feeding on juvenile roach Rutilus rutilus. Tyulka, an inhabitant of riverbed zones, remains the main prey for individuals older than 6+.