The present study evaluated the phylogenetic relationships among the six valid species of catfish of the genus Hypophthalmus , estimated the divergence times among the different taxa and assessed the processes that influenced the evolution of the group. All the phylogenetic analyses, based on 6803 base pairs, including three mitochondrial and seven nuclear markers, support the monophyly of Hypophthalmus , and the arrangement o...

Ecological forecasting models play an increasingly important role for managing natural resources and assessing our fundamental knowledge of processes driving ecological dynamics. As global environmental change pushes ecosystems beyond their historical conditions, the utility of these models may depend on their transferability to novel conditions. Because species interactions can alter resource use, timing of reproduction, and...

Acoustic deterrents can reduce marine mammal interactions with fisheries and aquacultures, but they contribute to an increasing level of underwater noise. In Southern California, commercially produced explosive deterrents, commonly known as “seal bombs,” are used to protect fishing gear and catch from pinniped predation, which can cause extensive economic losses for the fishing community. Passive acoustic monitoring data colle...

Probabilistic near‐term forecasting facilitates evaluation of model predictions against observations and is of pressing need in ecology to inform environmental decision‐making and effect societal change. Despite this imperative, many ecologists are unfamiliar with the widely used tools for evaluating probabilistic forecasts developed in other fields. We address this gap by reviewing the literature on probabilistic forecast eva...

The pathological changes induced by an infection of Diphyllobothrium dendriticum (Nitzsch, 1824) plerocercoids in powan, Coregonus lavaretus (L.), from Loch Lomond, Scotland, were assessed using immunohistochemical and ultrastructural techniques. In a sample of 26 powan, the occurrence of encysted plerocercoids of D. dendriticum on the outer surface of the stomach was 38.5% ( n = 10) with the number of cysts ranging from 4 to...

The effect of osmotic shock was investigated mainly in the chloride cells (CCs) and rodlet cells (RCs) of gills, and RCs of intestine and kidney of the European sea bass Dicentrarchus labrax obtained from a farm in the northern Adriatic Sea. During the experiment, fish were abruptly transferred from sea water to a salinity of 15 (15 SW) or to fresh water (FW). Numeric variation and ultrastructural changes of both cell types we...

Immunohistochemical examination of the galaninergic and the diffuse endocrine systems of the alimentary canal of three catfish species, Ameiurus melas, Silurus glanis and Clarias gariepinus showed the presence of galanin‐like immunoreactive endocrine cells in the stomachs and the proximal intestines and a galanin‐like immunoreactivity within the enteric intramural neurons. The three species differed notably in the relative abu...

A histopathological and immunohistochemical study on the intestines of 45 specimens of farmed rainbow trout, Oncorhynchus mykiss (Walbaum), from Loch Awe, Scotland, revealed a number of cellular deviations in individuals naturally infected with the pseudophyllidean cestode Eubothrium crassum (Bloch, 1779). Twenty‐five individuals (55.5%) were infected with an average worm burden of 18.84 ± 4.06 (mean ± SE) cestodes per host (r...

Handling stress and exposure to the herbicide Stam® M‐4 (Propanil) were associated with an exponential depletion of the rodlet cells (RC) in the bulbus arteriosus of chub Leuciscus cephalus . Structural changes of the RC in herbicide‐exposed fish were encountered, including the occurrence of myeloid bodies in the cytoplasm of the RC of the intestine, various degrees of rodlet degeneration and high vacuolization in the cytoplas...

The histopathology, immunohistochemistry and ultrastructure of the alimentary canal of chub, Leuciscus cephalus (L.), from the River Brenta, naturally infected with the acanthocephalan Pomphorhynchus laevis Müller, 1776, was studied and described. Of 62 chub examined, 54 (87%) were infected with P. laevis ; the intensity of infection ranged from five to 130 parasites per host, and a density of 8 P. laevis per cm 2 was common....

In the bulbus arteriosus of goldfish Carassius auratus a subendothelial ‘reticular space’ was comprised of reticular‐like cells, neutrophils, medium‐sized granular leucocytes, phagocytes, endothelial cells and reticulo‐endothelial cells; herein, rodlet cells (RCs) accumulated and probably matured. Four classes of RCs were identified: (1) Those occurring in the reticular space and contacting reticular‐like cells; (2) those pres...