The genus Grillotia Guiart, 1927 is cosmopolitan in its distribution and the type-species, G. erinaceus (van Beneden, 1858), has been relatively well studied. However, this study provides infection indices of Grillotia erinaceus from southern and northern Black Sea whiting Merlangius merlangus for the first time. The specimens of Grillotia erinaceus were obtained from subserosa of the anterior oesophagus, stomach, pyloric caeca, liver, ovaries and mesenterium of whiting caught by commercial fishing vessels off Sinop, Turkey and off Balaklava, Ukraine. Fish were examined during the period from May 2011 to April 2012. Prevalence and mean intensity values in 268 fish collected off Sinop in the Black Sea were 18.66% and 1.82 ± 0.16 parasites per infected fish, respectively. In Ukrainian 166 whiting samples collected off Balaklava in the Black Sea, however, G. erinaceus plerocercus infection prevalence was 10.24% and mean intensity 1.71 ± 0.75 parasites per infected fish. Infection parameters were also determined at both sampling sites in relation with host length, sex and season.

Trichodina gobii was identified during a parasitological survey conducted on the parasite fauna of whiting, Merlangius merlangus at both Sinop (Turkey) and Sevastopol (Russia) coasts of the Black Sea in the period between May 2011 and March 2014. Its morphological characteristics and taxonomic affinities with other previous reports on this species were revealed. The ecological occurrences in relation with seasonality, host length and sex of whiting were also determined. Parasitological indices were calculated from 690 and 423 whiting specimens collected in Sinop and Sevastopol, respectively. Overall infestation prevalence (%) and mean intensity and mean abundance values were 45.6%, 70.1±10.4 and 32.0±4.9, respectively, in Sinop, while they were 6.9%, 29.2±10.1 and 2.0±0.8 in Sevastopol. The taxonomic affinities to other trichodinid species and ecological data are discussed in detail.

SummaryIn the present study, we investigated the comparative infection levels, ecology and host-parasite interrelationship of a nematode Hysterothylacium aduncum (Rudolphi, 1802) in whiting, Merlangius merlangus (L., 1758) in southern (Sinop) and northern (Balaklava Bay) coasts of the Black Sea for the fi rst time. Fish were collected throughout a period from May 2011 to March 2014 from local fi shermen. A total of 690 fi sh specimens near Sinop and 423 fi sh near Balaklava Bay were examined for parasites. Hysterothylacium aduncum was the only nematode species identifi ed in the digestive tract of the Black Sea whiting Merlangius merlangus. Prevalence of infection, mean intensity and mean abundance values were determined according to season, length classes and sex of fi sh at both localities. These infection indices were always higher in Sinop samples than those of Balaklava Bay samples.

Juvenile golden grey mullet, Liza aurata were collected from Sarıkum Lagoon Lake which connected to the Black Sea at Sinop, Turkey and examined for parasitic fauna. A total of 219 fish were investigated throughout a 1-year period. Parasite species recovered were Trichodina lepsii, T. puytoraci, Gyrodactylus sp., Ligophorus cephali, Ligophorus mediterraneus, Solostamenides mugilis, Ascocotyle sp. (metacercaria) and Ergasilus lizae. Overall infection prevalence (%) and mean intensity values were 95.9% and 412.65 ± 85.31 parasites per infected fish, respectively. Infection prevalence and mean intensity values for each parasite species in relation to season and fish size were also determined and discussed. While Ligophorus cephali and L. mediterraneus are new records for Turkish parasite fauna, the juvenile Liza aurata is a new host record for Ligophorus cephali and L. mediterraneus.

Objective: The aim of the present study was to investigate and compare metazoan parasite faunas of three gobiid fishes, Neogobius fluviatilis, Proterorhinus marmoratus, and Pomatoschistus marmoratus, inhabiting the Lower Kızılırmak Delta. Methods: Fish specimens were caught using fishing nets and electroshock device. The fishes were transferred to the laboratory and examined under a dissecting microscope for metazoan parasites using conventional methods. The isolated parasites were fixed with 70% ethyl alcohol. The Czekanowski-Sørensen Index (ICS) was used for comparing the metazoan faunas of the three gobiid fishes. Results: Overall, 13 metazoan parasite species comprising 2 monogeneans (Gyrodactylus proterorhini and Gyrodactylus sp.), 6 digenean metacercariae (Tylodelphys clavata, Diplostomum spathaceum, Apatemon gracilis, Posthodiplostomum sp., Ascocotyle sp., and Echinostoma sp.), 1 cestoda (Bothriocephalus acheilognathi), 3 nematodes (Spiroxys contortus, Eustrongylides excisus, and Contraceacum rudolphii), and 1 arthropoda Ergasilus (sieboldin) were observed. The maximum parasite diversity was found in N. fluviatilis; Po. marmoratus had significantly fewer parasitic species (4). Total parasite abundance was significantly high in Pr. marmoratus, which was infected with 9 parasite species. A closer resemblance was observed in the parasite faunas of N. fluviatilis and Pr. marmoratus (ICS=80.0%). Conclusions: To the best of our knowledge, this is the first study on metazoan parasite faunas of N.