Rugulopteryx (Dictyotales, Phaeophyceae), a genus recently introduced to the Mediterranean

Abstract

The introduction of a common Western Pacific representative of the Dictyotales, Rugulopteryx okamurae (Dawson) I.K. Hwang et al., in european waters was demonstrated for the first time. The species was collected in the coastal lagoon of Thau (France, Mediterranean) in 2002. The specimens from Europe are described and compared with R. okamurae. Their conspecificity with northwest Pacific populations is confirmed based on morphological and comparative sequence analysis of the plastid-encoded psbA gene. Rugulopteryx okamurae is probably introduced in the Thau lagoon along with Japanese oysters, Crassostrea gigas (Thunberg 1793), imported into Europe for mariculture purposes. Since its introduction, although reproductive structures were not observed, R. okamurae has established self-sustaining populations without displaying an invasive behaviour. Rugulopteryx okainurae can be expected to turn up wherever C. gigas is reared

Four new exotic red seaweeds on European shores

“…Like Gelidium vagum and Gracilariopsis chorda, most recent seaweed introductions into Europe during the last decade have involved species originating from the north-western Pacific, such as Rugulopteryx okamurae, Polyopes lancifolius and Hypnea flexicaulis (Verlaque et al 2009;Mineur et al 2010b;Wolf et al 2011). It is consistent with the biogeography of the genera to infer that the north-western Pacific could also be a potential origin for the unknown species of Solieria and Chondracanthus.…”

“…For instance, Polyopes lancifolius was restricted to only a small area of the Gulf of Morbihan in 2008 and 2009 (Mineur et al 2010b), until it was observed on the shores of Jersey in the Channel Islands in the spring of 2011 (Chambers 2011). Similarly, while the brown seaweed Rugulopteryx okamurae may still be restricted to the Thau Lagoon, where it has been regularly recorded since 2002 (Verlaque et al 2009), large quantities of fragments have been observed in association with the edible sea urchin Paracentrotus lividus sold in a food market several hundred kilometres away (Verlaque, personal observation), showing a potential pathway for secondary introductions.…”

European seaweeds under pressure: Consequences for communities and ecosystem functioning

“…Bertuccio et al, 2011;Manghisi et al, 2010). Other alien red algae (Mineur et al, 2012b;Wolf et al, 2011), including many Halymeniales (De Clerck et al, 2005;Gavio and Fredericq, 2002;Mineur et al, 2010b;Verlaque et al, 2005), as well as brown seaweeds (Verlaque et al, 2009) In Europe and the Mediterranean Sea, more than 125 species of seaweeds are considered to have been introduced. The large majority of introductions occurred after the mid20th century.…”

SPECIES DELIMITATION, TAXONOMY, AND BIOGEOGRAPHY OF DICTYOTA IN EUROPE (DICTYOTALES, PHAEOPHYCEAE)1

“…(1992a) and De Clerck (2003) expressed doubt about the widespread nature of most species, but these claims have never been tested with DNA sequence data. Third, recent reports of alien species, Rugulopteryx okamurae (formerly D. okamurae ; Verlaque et al. 2009) and D. ciliolata Sond.…”