Many teleost fishes produce sounds for social communication with mechanisms that do not involve swim bladder musculature. Such sounds may reflect physical attributes of the sound-production mechanism, be constrained by body size and therefore control signal reliability during agonistic behaviors. We examined kinematics of the cranium, median fins and caudal peduncle during sound production in t...

To date, the monospecific Dendrorchis is represented by D. neivai, reported from Brazil and parasitizing Brycon lundi. Dendrorchis retrobiloba n. sp. is described from the swim bladder of Astyanax fasciatus from Cañada del Dragón stream in Montevideo, southern Uruguay (34 degrees 47'S, 56 degrees 14'W), and the emended diagnosis of Dendrorchis is given. The diagnosis of Dendrorchis has been mod...

This study deals with the redescription of Sillago indica based on seventy-two specimens measuring (139.2-192.4 mm SL), obtained from the fish market in Weifang City, China, in March 2014, these fishes were originally captured in the coastal waters of Pakistan. The meristic counts as: dorsal fin rays XI, I, 20~22; anal fin rays II, 21~23; pectoral fin rays 16~17; pelvic fin rays I, 5; caudal fi...

Elucidating the origins of complex biological structures has been one of the major challenges of evolutionary studies. Within vertebrates, the capacity to produce regular coordinated electric organ discharges (EODs) has evolved independently in different fish lineages. Intermediate stages, however, are not known. We show that, within a single catfish genus, some species are able to produce soun...

In conjunction with habitat loss and overfishing, pollution and parasitism are believed to be relevant causes of collapse of Anguilla, as these can affect eel swimming ability and the development of gonads and embryos. The present study investigated Persistent Organic Pollutant (POP) concentrations, infection levels of Anguillicoloides crassus, lipid content and gonad abnormalities in eels samp...

Little is understood regarding the impacts of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure during early development on the health, survival, and reproductive capability of adults. Here we use zebrafish to determine whether early life stage exposure to TCDD induces toxicity in adult zebrafish and their offspring. Zebrafish were exposed to graded concentrations of TCDD (0-400 pg/ml) via wa...

Each year, over 45 countries export 30 million fish from coral reefs as part of the global marine ornamental aquarium trade. This catch volume is partly influenced by collection methods that cause mortality. Barotrauma in fish resulting from forced ascent from depth can contribute to post-collection mortality. However, implementing decompression stops during ascent can prevent barotrauma. Conve...

During a study of myxosporean parasites of cultivated freshwater fish, a new myxosporean species, Henneguya pellucida n. sp., was discovered. Of the 120 Piaractus mesopotamicus sampled, only 10 specimens (8.3%) were infected. Yellow, round plasmodia measuring 0.5-3 mm were found in the serous membrane of the visceral cavity and in the tunica externa of the swim bladder. Sporogenesis was asynchr...

The commercial importance of Pacific and Atlantic herring (Clupea pallasii and Clupea harengus) has ensured that much of their biology has received attention. However, their sound production remains poorly studied. We describe the sounds made by captive wild-caught herring. Pacific herring produce distinctive bursts of pulses, termed Fast Repetitive Tick (FRT) sounds. These trains of broadband ...