Читать книгу Clinical Guide to Fish Medicine - Группа авторов - Страница 58

Most eels are within the Anguilliformes. Important families include freshwater eels (Anguillidae) and moray eels (Muraenidae). Some freshwater eels are important food fish, e.g. European eel (Anguilla anguilla), short‐finned eel (Anguilla australis), Japanese eel (Anguilla japonica), and American eel (Anguilla rostrata). These have complicated life cycles including freshwater and marine life stages (catadromous, moving from freshwater to saltwater to spawn) and long migrations. Some moray eels are common in display aquaria, e.g. green morays (Gymnothorax funebris) and zebra morays (Gymnomuraena zebra). They lack a pelvic girdle and most also lack a pectoral girdle. Scales are typically absent, but if present, they are cycloid and embedded. Moray eels have two sets of jaws: oral and pharyngeal (Figure A1.8). Eels can inflict a painful bite on handling. The gill opening is narrow and visualization of gills is difficult without endoscopy. The swim bladder has a single lobe (Trischitta et al. 2013). Radiographs have been used for diagnosis of swim bladder nematodes in Anguillidae (Palstra et al. 2007).