Showing papers in "Arquipelago : Life and Marine Sciences in 2019"
TL;DR: The clingfish Apletodon gabonensis sp. nov as discussed by the authors is described on the basis of seven specimens and colour photographs from Gabon, eastern Atlantic Ocean, and is small, apparently not exceeding 20 mm total length; it is characterized by having 5 dorsal fin rays, 4-5 anal-fin rays, 25-27 pectoral fin rays and head width in males 2.6-4.7 in SL, anus in males with urogenital papilla present but not pronounced.
Abstract: The clingfish Apletodon gabonensis sp. nov. is described on the basis of seven specimens and colour photographs from Gabon, eastern Atlantic Ocean. The species is small, apparently not exceeding 20 mm total length; it is characterized by having 5 dorsal-fin rays, 4-5 anal-fin rays, 25-27 pectoral-fin rays, head width in males 2.6-4.7 in SL, anus in males with urogenital papilla present but not pronounced; snout long, broad, anteriorly truncate in male, narrower and rather pointed in female; preorbital length 1.8-3.8 in head length; conspicuous maxillary barbel absent in both sexes; disc with 10-12 rows of papillae in region A, 5 rows of papillae in region B, and 5-7 rows of papillae in region C. The new species is compared with the other species of the genus; a key to the males of the 6 known species of the eastern Atlantic genus Apletodon is presented.
1 citations
TL;DR: In this paper, the optimal conditions for Pterocladiella capillacea production in the Azores were determined using von Stosch medium, and the best relative growth rate (RGR) was recorded at 150 μmol photons m−2 s−1 for the entire thalli and tips after two weeks and three weeks, respectively, indicating that an acclimation period is necessary to assure the growth of this alga under experimental conditions.
Abstract: Pterocladiella capillacea has been economically exploited for agar extraction in the Azores for many years. Harvesting dropped to a full stop in the early 1990s due to a population collapse, but restarted in 2013. Since then it has been intensively harvested and overexploitation must be prevented, with both sustainable harvesting and effective cultivation practices. This study represents the first attempt to determine optimal conditions for P. capillacea production in the Azores, and evaluates its vegetative growth in two experiments using von Stosch’s medium designed to test entire thallus and tips portions response to different irradiances (30, 70 and 150 μmol photons m-2 s-1). The best relative growth rate (RGR) was recorded at 150 μmol photons m−2 s−1 for the entire thalli and tips after two-weeks and three-weeks, respectively, indicating that an acclimation period is necessary to assure the growth of this alga under experimental conditions. Higher RGR was obtained at higher irradiance (3.98 ± 2.10% fm day-1), but overall, growth rates were low or negative. Epiphytes were a serious problem towards the end of the entire thallus experiments, where Feldmannia irregularis proliferate at all irradiances. Future cultivation approaches complemented with other relevant environmental factors (e.g. pH, photoperiod, salinity), are recommended.
1 citations