Experimental results showed that the gill monogenean Cichlidogyrus sclerosus and its host, the Nile tilapia Oreochromis niloticus, exhibited significant numerical and physiological responses after exposure to sediments polluted with polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, and heavy metals in comparison with control fishes. After 15 days of exposure, C. sclerosus abundance significantly increased in treatments with low to fairly high sediment pollutant concentrations, but declined at high sediment pollutant concentrations. Hypertrophy and hyperplasia in secondary gill lamellae and the spleen melanomacrophage centers were significantly higher at extremely high sediment pollutant concentrations compared with the controls. Spleen lymphocyte and monocyte counts were significantly lower at extremely high sediment pollutant concentrations and were significantly correlated with high fluorescent aromatic compound concentrations measured as PAH exposure indicators. A multivariate redundancy analysis showed significant statistical association between sediment pollutant concentration, C. sclerosus abundance, and tilapia physiological variables. The polluted sediments negatively affected monogenean abundance and induced immunosuppression in hosts, consequently increasing histological damage in hosts and allowing persistent C. sclerosus infection. This study documents evidence suggesting that C. sclerosus and its host are indeed excellent models to test environmental quality in tropical freshwater ecosystems.

The present study documents the first finding of Panulirus argus Virus 1 (PaV1) in spiny lobster Panulirus argus from Cuba. Samples originated from 2 nursery sites, Matías Keys and Bocas de Alonso Keys, and 2 fishing sites, La Grifa and El Ramajo. Lobsters from the nursery sites (artificial reefs) were collected by SCUBA diving, while those from the fishing sites were collected from artificial shelters known as 'casitas cubanas'. In these shelters it was observed that healthy lobsters tended to avoid infected lobsters. Prevalence of PaV1 in the sampling sites was assessed by using clinical signs such as lethargy, an opaque reddish shell coloration, and milky white hemolymph with loss of clotting activity. The presence of PaV1 was subsequently confirmed by histology and PCR of tissues and hemolymph samples from suspected individuals. Histological sections of the hepatopancreas, gills, gonads, and gut showed infected hemocytes with hypertrophied nuclei and eosinophilic intranuclear Cowdry type A inclusions. A 499 bp band was observed by PCR. The sequence of the amplified fragments was 96% similar to the PaV1 sequence in GenBank. The overall mean prevalence of PaV1 was 4.48% (range: 0 to 9.3%) after pooling the results of the 4 sampling sites.

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A new nematode species, Philometra (Ranjhinema) salgadoi n. sp., is described from females found in the ocular cavity of the red grouper (Epinephelus morio) from the Mexican coast of the Gulf of Mexico (type locality Telchac, Yucatán). The nematode is characterized by the presence of 8 conspicuously large, crescent-shaped, fleshy cephalic papillae of the external circle and 2 small, subterminal papilla-like projections on the caudal end. Another philometrid species, Philometroides belousae n. sp., is established by indication for P. parasiluri (Yamaguti, 1935) sensu Ermolenko, 1984; its adult females are parasitic in the subcutaneous tissues of Percottus glehni in the Russian Far East.

We surveyed copepods parasitic on the fishes at Palmyra, a remote atoll in the Central Indo-Pacific faunal region. In total, we collected 849 individual fish, representing 44 species, from the intertidal lagoon flats at Palmyra and recovered 17 parasitic copepod species. The parasitic copepods were:OrbitacolaxwilliamsionMulloidichthysflavolineatus;AnuretesserratusonAcanthurusxanthopterus;CaligusconfususonCarangoidesferdau,Carangoidesorthogrammus,Caranxignobilis,Caranxmelampygus, andCaranxpapuensis;CaliguskapuhilionChaetodonaurigaandChaetodonlunula;CaliguslaticaudusonRhinecanthusaculeatus,Pseudobalistesflavimarginatus,M.flavolineatus,Upeneustaeniopterus,Chrysipteraglauca, andEpinephalusmerra;CaligusmutabilisonLutjanusfulvusandLutjanusmonostigma;CaligusrandallionC.ignobilis;Caligussp. onL.fulvus;CaritusserratusonChanoschanos;LepeophtheiruslewisionA.xanthopterus;LepeophtheirusuluusonC.ignobilis;DissonussimilisonArothronhispidus;Nemesissp. onCarcharhinusmelanopterus;HatschekialongiabdominalisonA.hispidus;HatschekiabicaudataonChaetodonaurigaandChaetodonlunula;KroyerialongicaudaonC.melanopterusandLernanthropussp. onKyphosuscinerascens. All copepod species reported here have been previously reported from the Indo-Pacific but represent new geographical records for Palmyra, demonstrating large-scale parasite dispersion strategies.