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In this study, we determined the genomic DNA sequences of the mucosal galectin-encoding genes from all 19 species and subspecies of the genus Anguilla. The nucleotide sequences of the galectin genes were c. 2.3-2.5 kb long and the organisation of their four exons and three introns was conserved in all species. An unusual sequence was found in the fourth exon of Anguilla reinhardtii, resulting in a unique deduced amino-acid sequence at the C-terminus. All six amino-acid residues important for β-galactoside binding were conserved in three species, while one residue (R73 ) was substituted to K73 in the other 16 species-subspecies, including Anguilla marmorata. However, this substitution did not appear to affect the sugar-binding ability of galectins because the galectin of A. marmorata was previously shown to bind to lactose. We also discuss the molecular evolution of galectins among Anguilla spp. and the homologues previously identified in Conger myriaster.

Longfinned eels Anguilla reinhardtii were captured by both fishery-dependent and independent sampling methods from three rivers in New South Wales, south-eastern Australia. Growth rates were examined in two zones (fresh water and tidal) in the Hacking, Hawkesbury and Clarence Rivers. Mean annual growth increments of sampled longfinned eels ranged from 30 to 60 mm year-1 using age-length analyses and up to 167 mm year-1 based on tag-recapture model estimates (GROTAG), with both methods showing high intra- and inter-population variability. Growth was significantly faster in younger (5-15 years) fish than older (>15 years) fish, with females growing an average 10 mm year-1 faster than males of similar age and capture location. Longfinned eels found in tidal areas grew significantly faster than those in non-tidal freshwater areas as a result of longer growing seasons in the highly productive estuarine habitats. Other possible factors influencing variability in growth rates for this species include habitat preference, density and fishing pressure. © 2006 The Fisheries Society of the British Isles.

The sex and stage of gonadal development of longfinned river eels Anguilla reinhardtii, captured from nine river catchments in New South Wales, Australia, between 1999 and 2001, were determined macroscopically. Sex was verified by histology. Histology was also necessary, however, to accurately define stages of gonadal development, particularly in individuals