Solieria sp. Į. Agardh, 1842

Burel, Thomas, Helias, Mathieu & Duff, Michel Le, 2023, Range expansion of some non-indigenous seaweeds along the coasts of Brittany - English Channel, Botanica Marina (Warsaw, Poland) 66 (3), pp. 151-164 : 157

3.6 Solieria sp. Į. Agardh, 1842

Solieria sp. has been present since at least 2005 in the Gulf of Morbihan, and was also detected in 2011 in the Thau Lagoon ( Mineur et al. 2012). This species, first identified and sequenced by Mineur et al. (2012), is a NIS for Brittany and closely related, morphologically and molecularly, to unidentified specimens first detected in New Zealand in 1992. Furthermore specimens from both locations are closely related to Solieria chordalis (C. Agardh) J. Agardh and Solieria fi liformis (Kützing) Gabrielson ( Fredericq et al. 1999; Mineur et al. 2012). Specimens in both localities were lacking conspicuous reproductive structures. Solieria sp. specimens from Morbihan ranged from 5 to 26 cm long, with a pale-red to orange-red color ( Figure 9a ). Main axes were 500–1570 µm wide. The ramifications were irregular to sub-dichotomous, straight and bearing tapering apices ( Figure 9b ). Plants that have been dried for herbarium leave behind a characteristic brown mark on the paper. Plants of Solieria sp. can be distinguished from S. chordalis by a bright orange color ( S. chordalis plants are red to dark-red), by the larger axes and the irregular branching pattern. Specimens of Solieria sp. can also be misidentified as Gracilaria spp. ( Nelson et al. 2015), but in transverse section, Solieria plants have a two-part medulla with big round cells surrounding more elongated rhizoidal cells, while Gracilaria spp. have a medulla only composed of rounded cells.

Figures

Figure 9: Solieria sp. from Brittany: (a) in situ material from Locmiquel (picture by M. Helias);(b) dried specimen from the Gulf of Morbihan.Scale bar: 2 cm.