REVISION OF DECACOTYLINAE CHISHOLM, WHEELER AND BURTON,BEVERLEY, 1995(MONOGENEA, MONOCOTYLIDAE), INCLUDING THE SYNONYMY OF PAPILLICOTYLE YOUNG, 1967 WITH DECACOTYLE YOUNG, 1967 AND A DESCRIPTION OF A NEW SPECIES FROM AUSTRALIA

Close examination of type and new material of Decacotyle lymmae Young, 1967 revealed the presence of two unsclerotised structures on the dor sal surface of the haptor which were overlooked in the original descri ption. We demonstrate that Papillicotyle Young, 1967, distinguished pr eviously from Decacotyle Young, 1967 in part by the presence of unscle rotised accessory structures on the dorsal surface of the haptor, is s ynonymous with Decacotyle. D. tetrakordyle n. sp, is described from th e gills of Pastinachus sephen (Forsskal) collected from Heron Island, Great Barrier Reef, Australia. D. tetrakordyle n. sp. is distinguished from the other four species in the genus by the presence of four acce ssory structures on the dorsal surface of the haptor and a complex mal e copulatory organ. Additional specimens of D. lymmae Young, 1967 from the gills of Taeniura lymma (Forsskal) and D. floridana (Pratt, 1910) n. comb and D. octona (Young, 1967) n. comb from the gills of Aetobat us narinari (Euphrasen) were also collected from the Queensland coast, Australia in the present study: D. youngi (Timofeeva, 1983) n. comb. is also transferred to Decacotyle from Papillicotyle. The Decacotylina e Chisholm, Wheeler & Beverley-Burton, 1995 is revised based on examin ation of type material, material of the new species and additional mat erial of three previously described species. The oncomiracidium of D. floridana is described. A key to species is given and a description is provided of anterior glands containing needle-like secretion located lateral to the pharynx not described previously in D. lymmae. The disc overy of D. floridana at Heron Island and D. octona in Moreton Bay rep resent new locality records for these species.