TRIGONOSTOMUM WATSONI SP. NOV.

(FIG. 7B)

Alternative species name: trigonostomum-watsoni sp. nov.

Holotype: Whole mount, Australia, New South Wales, Arrawarra, on Pavonina -like algae in shallow tidepool between rocks near beach, 27 August 1996.

Paratype: One whole mount.

Other material: Observations on live material. Six whole mounts and six serially-sectioned specimens, Australia, New South Wales, Lennox Head, on beach with coarse sand and on algae in tide pool, 27 October and 1 November 1997 . One whole mount, Australia, New South Wales, Arrawarra, on Sargassum sp. in permanent pool, 27 August 1996 . One whole mount, Australia, New South Wales, Arrawarra, Mullaway headland, on algae in deep rock pools, 24 July 2003 . Two whole mounts, New Caledonia, Nouméa, Magenta, permanent pool near mangroves, on large algae covered with epiphytes, 22 August 2003 .

Etymology: Dedicated to Dr Nikki Watson, Armidale, Australia, who assisted with the collection of material at Arrawarra.

Diagnosis: Trigonostomum species with copulatory organ 28–36 Mm long. Stylet 29–41 Mm long, proximally bent over 90∞. Mantle with three spine-like plates surrounds only the distal part of the stylet. Bursal appendage 62–78 Mm long, with two coiled (more than 360∞) striated tubes.