RESUMO
In the Colombian Caribbean, the marine macroalgal flora of the Seaflower International Biosphere Reserve has been little studied, despite its ecological importance. Historical records have reported only 201 macroalgae species within its area of almost 350 000km². However, recent surveys have shown a diversity of small algae previously overlooked. With the aim to determine the macroalgal diversity in the Reserve, we undertook field surveys in different ecosystems: coral reefs, seagrass beds, and rocky and sandy substrates, at different depths, from intertidal to 37m. During these field surveys, we collected a small described species belonging to the genus Crouania (Callithamniaceae, Rhodophyta), Crouania pumila sp. nov. that is decribed in this paper. This new species was distinguished from other species of the genus by a distinctive suite of traits including its diminutive size (to only 3.5mm in length), its decumbent, slightly calcified habit (epiphytic on other algae), its ramisympodial branching, the ecorticate main axes, and the elongate shape of the terminal cells of the cortical filaments. The observations were provided for both female (cystocarpic) and tetrasporangiate thalli; however, male thalli were not seen. Further studies have to be undertaken in this Reserve in order to carry out other macroalgal analysis and descriptions.
Crouania pumila sp. nov. (Ceramiaceae, Rhodophyta) es descrita para la isla de Providencia, en el Caribe colombiano. La nueva especie se destaca de las otras especies del género por características como su tamaño diminuto (hasta 3.5mm de largo), su hábito decumbente y poco calcificado (epífita sobre otras algas), su ramificación ramisimpodial, la ausencia de corticación y la forma alargada de las células terminales de los filamentos corticales. Se proveen observaciones sobre talos femeninos (cistocárpicos) y tetraspóricos. No se observaron talos masculinos.
Assuntos
Ecossistema , Rodófitas/anatomia & histologia , Rodófitas/classificação , Região do Caribe , Colômbia , Densidade DemográficaRESUMO
Se registra la presencia del helecho invasor Pteridium caudatum (L.) Maxon en la isla de Providencia, Colombia. La especie ha sido encontrada como planta decorativa en jardines y patios, así como naturalizada en El Pico, la localidad boscosa con mejor estado de conservación de la isla. Se discuten las implicaciones ecológicas relativas a la presencia de esta especie.
We report for the first time the presence of the invasive fern Pteridium caudatum (L.) Maxon Old Providence Island, Colombia. The species was found as an ornamental plant in house backyards, as well as in the wild in the locality The Peak, the best preserved area of the island. We discuss the ecological implications associated to the presence of this species.