Aún lejos de un completo conocimiento de la biota canaria: el ejemplo de la flora de algas rojas gelatinosas efímeras del sublitoral

The marine flora of the Canary Islands is considered well-documented, but recent studies conclude that its present knowledge is still incomplete. In the last years, the study of unstable bottoms occupied by pebbles or rocks without perennial vegetation due to the abrasion by sand, it has allowed to discover a rich and diverse ephemeral flora, that was overlooked. This flora is constituted by species of Ganonema, Helminthocladia, Helminthora, Naccaria, Reticulocaulis, Acrosymphyton, Schimmelmannia, Calosiphonia, Dudresnaya, Thuretella and Predaea; genera with gelatinous gametophytes, heteromorphic life histories, and primitive structures and reproduction. In this paper we review the knowledge on this surprising flora, emphasizing the high diversity that it is to catalogue in many sulittoral habitats of the Canary Islands not yet sufficiently exploredLa flora marina de las Islas Canarias es considerada bien documentada, pero estudios recientes concluyen que su actual conocimiento es aún incompleto. En los últimos años, el estudio de fondos inestables ocupados por guijarros o rocas sin vegetación perenne debido a la abrasión por arena, ha permitido descubrir una rica y diversa flora efímera, que había pasado desapercibida. Esta flora está constituida por especies de Ganonema, Helminthocladia, Helminthora, Naccaria, Reticulocaulis, Acrosymphyton, Schimmelmannia, Calosiphonia, Dudresnaya, Thuretella y Predaea; géneros con gametófitos gelatinosos, alternancias heteromórficas de generaciones, y estructuras y reproducción primitivas. En este artículo revisamos los conocimientos sobre esta sorprendente flora, destacando la elevada diversidad que puede quedar por catalogar en muchos hábitats del sublitoral canario aún no suficientemente explorados

Gelidiales (Rhodophyta) en las Islas Canarias: estudios previos y perspectivas futuras

Gelidiales es un orden de algas rojas perteneciente a la clase Florideophyceae que está constituido por cuatro familias reconocidas genéticamente: Gelidiaceae, Gelidiellaceae, Pterocladiaceae y Orthogonacladiaceae. Es un orden numeroso caracterizado en Canarias por 16 especies, algunas de ellas endémicas, formadoras de hábitats y con poblaciones en marcado declive en las últimas décadas. El objetivo de este trabajo es revisar todos los estudios previos publicados sobre Gelidiales en las islas Canarias con el fin de sintetizar y mostrar su protagonismo en las comunidades bentónicas marinas del archipiélago. Esta síntesis también identifica aquellos vacíos de conocimiento que necesitan ser abordados para predecir cambios futuros en los ecosistemas marinos de Canarias y proponer planes de conservación y/o recuperación de sus poblaciones en las islas.Gelidiales is a red algae order which belongs to the class Florideophyceae and comprises four genetically recognized families: Gelidiaceae, Gelidiellaceae, Pterocladiaceae and Orthogonacladiaceae. It is a copious order characterized in the Canary Islands by 16 species, some of which are endemic and canopy-forming with populations in unforeseen decline over the last four decades. The aim of this article is to examine all previous studies into the Gelidiales in the Canary Islands, in order to synthesize and demonstrate the relevance of these species to the benthic marine communities of the archipelago. This review also identifies those knowledge gaps that need to be addressed to predict future changes in the marine ecosystems and suggest conservation and/or recovery plans for their populations

Comunidades de macroalgas bentónicas de la isla de La Palma (Islas Canarias): distribución vertical y longitudinal

Sangil, C., M. Sansón & J. Afonso-Carrillo. 2014. Comunidades de macroalgas bentónicas de la isla de La Palma (Islas Canarias): distribución vertical y longitudinal. Revista de Estudios Generales de la Isla de La Palma 6: 119-138.En el presente trabajo se realiza un estudio de la distribución de las comunidades de macroalgas en el intermareal y submareal de la isla de La Palma. En el intermareal el principal factor de variación es la altura sobre el nivel de las mareas. El modelo de zonación de los organismos [ litoral; poblaciones de Gelidium pusillum y Chthamalus stellatus en el eulitoral superior, algas pardas costrosas en los niveles medios del eulitoral y céspedes [ Mientras que los niveles superiores son similares a lo largo de toda la isla, el nivel inferior presenta diferencias en función del grado de exposición al oleaje. En el submareal, las principales diferencias entre comunidades son debidas a la actividad de los herbívoros. Podemos diferenciar los fondos dominados por especies costrosas de fondos dominados por espacies frondosas. En estos últimos fondos de Lobophora variegata; fondos dominados por Cystoseira abies-marina; comunidades de coralináceas articuladas y dictiotáceas; y fondos someros ocupados por gelidiáceas.In the present paper a study of the distribution of seaweed assemblages of the intertidal and subtidal of La Palma Islands is made. Ordination (PCA) was used to analyse the data. The principal factor of variation in the intertidal is the height of the shore. The zonation model of organisms is the following: cyanophytes in the littoral fringe; populations of Gelidium pusillum and Chthamalus stellatus in the upper eulittoral; crustose brown algae in the middle eulittoral; and algal turfs in the lower intertidal. While the upper levels are similar around the island, the lower levels present differences dependent of the wave exposure. In the subtidal, the principal differences between assemblages are produced by the activity of the sea urchin Diadema aff. antillarum, originating barren grounds, bottoms of crustose algae, opposite to erect algal assemblages. In the latter we identify four types of assemblages: Lobophora variegata bottoms; assemblages of articulated coralline algae and dictiotaceae; shallow bottoms occupied by Cysroseira abies-marina or gelidiaceae; and Liagora populations

Morphology and anatomy of Spongites africanum comb. nov. (Corallinaceae, Rhodophyta) from the Cape Verde Islands

Afonso-Carrillo, J., M. Chacana & M. Sansón. 1993. Morphology and anatomy of Spongites africanum comb. nov. (Corallinaceae, Rhodophyta) from the Cape Verde Islands. CFS Courier Forschungsinstitut Senckenberg 159: 133-137.On the basis of critical studies on the morphology and anatomy of the holotype collection and new material from the Cape Verde Islands, Lithophyllum africanum FOSLIE (= Porolithon africanum (FOSLIE) FOSLIE) is transferred to the genus Spongites KUT ZING. Plants of Spongites africanum (FOSLIE) AFON SO-CARRILLO, CHACANA & SANSON comb. nov. form subhemispherical masses, about 10 cm diameter, with a crustose portion and numerous compressed and confluent erect protuberances. Three of the five characters used to circumscribe Spongites are present in the holotype of Lithophyllum africanum: cells of contigous filaments interconnected by cell fusions, thallus composed of numerous layers of cells and normally over 200 pm thick and thallus devoid of a coaxial core of filaments. Uniporate tetrasporangial concept acles and tetrasporangia devoid of apical plugs, are the only characters not apparent in the holotype, but its are evident in the material examined from the Cape Verde Islands

Distribution and reproductive phenology of the seagrass Cymodocea nodosa (Ucria) Ascherson in the Canary Islands

Cymodocea nodosa (Ucria) Ascherson is the most common seagrass in the Canary Islands. Data about its insular distribution as well as observations on its flowering, fruiting and seed germination are shown. Cymodocea nodosa forms scattered meadows mainly along the southeastern coasts of these islands. The reproductive phenology was studied in meadows at E1 M6dano, south of Tenerife. Flowering was detected from March to July, when fertile shoots were observed. Fruiting began in April and fruits were observed attached to shoots until December. Throughout the year numerous fruits were detected buried in the sediment. Seed germination was observed from February to Septembe

Zonación del fitobentos en el litoral sureste y adiciones a la flora marina de La Palma (islas Canarias)

La zonación de las algas en el litoral sureste de la isla de La Palma fue estudiada en cinco localidades. Aunque en algunos niveles hay similitudes con los patrones de zonación observados en otras partes de la isla, la distribución vertical de las algas a lo largo de esta costa puede ser caracterizada por las singularidades encontradas en el eulitoral inferior y en el sublitoral somero. En el eulitoral inferior predomina una heterogénea comunidad cespi tosa constituida principalmente por Corallina elongata, Jania adhaerens, Stypocaulon sco parium, Cystoseira compressa, Lobophora variegata y Padina pavonica. En el sublitoral superior, no hay bandas de gelidiáceas y Cystoseira abies-marina forma una estrecha banda en lugares más expuestos, mientras que en aquellos algo más protegidos es sustituida por coralináceas articuladas, dictiotáceas, Stypocaulon scoparium y Asparagopsis taxiformis. Cuatro macroalgas (Gastroclonium clavatum, Helminthocladia reyesii, Scinaia caribaea y Petalonia fascia) se citan por primera vez para La Palma.The zonation of the seaweeds in the southeastern coast of the island of La Palma was examined in five localities. Although in some levels there are similarities with the patterns of zonation observed in other parts of the island, the vertical distribution of the seaweeds throughout this coast can be characterized by the singularities found in the lower eulittoral and in the upper sublittoral. In the lower eulittoral, a heterogeneous caespitose community mainly constituted by Corallina elongata, Jania adhaerens, Stypocaulon scoparium, Cystoseira compressa, Lobophora variegata and Padina pavonica is dominant. In the upper sublittoral, there are not bands of Gelidiaceae and Cystoseira abies-marina forms a narrow band at exposed places, whereas in slightly sheltered places is replaced by geniculate cora lline algae, Dictyotaceae, Stypocaulon scoparium and Asparagopsis taxiformis. Four sea weeds (Gastroclonium clavatum, Helminthocladia reyesii, Scinaia caribaea and Petalonia fascia) are reported for the first time from La Palma

Vegetative and reproductive morphology of Ganonema lubrica sp. nov. (Liagoraceae, Rhodophyta) from the Canary Islands

The marine red alga Ganonema lubrica sp. nov. (Liagoraceae, Nemaliales) from the Canary Islands is described. Gametophytes are terete, lubricous, lightly calcified, and radial to irregularly paniculately branched. Axes consist of many (18-26) primary medullary filaments that give rise to cortical fascicles with subcylindrical or clavate basal cells. Spermatangia form dense clusters on subterminal cortical cells, displacing the terminal cell laterally. Carpogonial branches are straight, five to eight cells in length, and arise from inner cortical supporting cells in positions occupied by adventitious cortical filaments. The carpogonium divides transversely and the upper half gives rise to a compact subhemispherical carposporophyte. Sterile filaments are absent or arise from the suprasupporting cell and partially or completely surround the carpogonial branch. Gonimoblastic rhizoids sometimes are present. Ganonema lubrica differs from previously described species of Ganonema and of the Mucosae group of Liagora mainly in the architecture of carpogonial branches, the shape of the basal cell of cortical fascicles, the derivation of most sterile filaments from the suprasupporting cell, and the occasional production of rhizoids from the gonimoblast