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September 17, 2014


BY: Oceana Web


*** Local Caption *** Expedition leader Ricardo Aguilar and marine scientist Helena Alvarez looking for specimens in the sponge sample. Tritón North, Spain. Ranger Expedition to the Atlantic Seamounts. September 2014. Ricardo Aguilar, coordinador de la expedición y Helena Álvarez, científica marina, buscando especímenes en una muestra de esponjas extraída con el ROV. Tritón Norte, España. Expedición del Ranger a las montañas submarinas del Atlántico. Septiembre 2014.


The glass sponges or hexactinellids are quite impressive. They consist of siliceous spicules, which draw many different geometric shapes, creating some of the most beautiful and unknown creatures on Earth. From the nearly 500 documented species a set of ten can be observed in the valley between the two peaks of the Triton seamount (around 900 meters deep). Our guide for Canary Islands sponges only includes four species for this area, in spite of  that, we suspect that some of the sponges observed have not been documented yet. Euplectella sp. or Regadrella sp., Aphrocallistes beatrix, Pheronema carpenteri, Farrea sp., Sympagella sp. e Hyalonema sp. are some of the possibilities we´ve considered so far, although this must be confirmed after a thorough analysis of the images and samples taken.

But sponges are not the one and only surprise of the day. Today´s dives have revealed the presence of other species such as deep-sea octopus Eledone cirrhosa and Octopus salutii, not to mention the impressive starfish Coronaster volsellatus and sea urchins like Centrostephanus longispinus, Coelopleurus sp., Cidaris cidaris, etc. In addition, we encountered with the so expected shark Deania cf. profundorum.

Tomorrow our journey will be heading to El Hierro, stopping in Santa Cruz de Tenerife, where the second phase of the campaign will begin in the Mar de las Calmas.