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We describe for the first time the morphology of Gelidium crinale from its natural habitat in Atlantic Patagonia with special consideration of diagnostic characters. Observations and morphometric measurements were done on fresh specimens using scanning electron and inverted light microscopy. This report is a new record for Atlantic Patagonian coasts. The thalli comprise prostrate and erect axes; they are subterete at the base and compressed to flattened at the apices. The basal parts are scarcely and irregularly branched, while the apical parts are highly ramified and subdichotomously branched. The lengths of thalli and the ramification patterns differ from previous descriptions, and were variable between seasons and life history phases. ´Brush-like´ haptera confirmed the identity of the algae as members of the Gelidiaceae. Internal rhizoidal filaments are abundant and distributed in groups throughout the medulla. The life history was of the ´Polysiphonia -type´ ; occurrences of carposporophytes and tetrasporophytes were variable. Fil: Croce, Maria Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Nacional del Sur; Argentina Fil: Parodi, Elisa Rosalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Nacional del Sur; Argentina

Polysiphonia morrowii, a species native to the North Pacific, is believed to have been introduced to Chile, Turkey, Italy and France. This species was first recorded from New Zealand in 2011, based on collections made in 2004 from two sites on South Island, but no commentary was provided in the distribution or characteristics of the material collected. In 2009, as part of a study on macroalgae associated with soft sediment habitats in New Zealand, several samples of P. morrowii were collected from Otago Harbour, a location already known to host 17 non-indigenous macroalgal species. However, this species has gone unnoticed in New Zealand. We present the current understanding of the distribution of this species in New Zealand, and the distinguishing features of the specimens collected, to assist with biosecurity and monitoring programmes. Including this report of P. morrowii, there are now seven species of Polysiphonia and Neosiphonia that are regarded as non-indigenous in New Zealand.

Polysiphonia morrowii Harvey (Rhodophyta), native to Japan, Korea, China and Russia, is here reported for the first time from the Mediterranean Sea. Thalli were first found in 1999 off the Island of Chioggia, where imported clams and fish are handled; the following year, plants were also found near the Island of Venice itself. Polysiphonia morrowii is similar to Polysiphonia senticulosa Harvey, as reported from Japan and the north Pacific, and to Polysiphonia stricta (Dillwyn) Greville [= Polysiphonia urceolata (Dillwyn) Greville] from the Mediterranean basin. The specimens collected in the Lagoon of Venice are characterised by two of the most significant specific features of P. morrowii: endogenous axillary branchlets forming from the central axial cells, and tufts of axillary tetrasporangial branchlets on the axils of mature plants. The morphology and reproduction of P. morrowii are examined on the basis of the material collected at Venice.