Eight deep-sea marine sponges species discovered

Deep-sea sponge species Geodia bibilonae is named in honour of scientist Maria Antònia Bibiloni. Image: Julio A Díaz.

Eight new species of marine sponges have been discovered around the Balearic Islands in the western Mediterranean, among a total of 36 species at home in the region.

Marine sponges are widespread across the planet, but their biodiversity and distribution is still poorly known. Even though the Mediterranean Sea is the most explored sea on Earth, a study by Julio Díaz, a PhD student at the Spanish Institute of Oceanography, reveals the presence of new sponge species in unexplored habitats such as underwater caves and mountains, descending to depths of up to a kilometre.

Sponges are aquatic animals that attach to the seafloor and feed on bacteria and other microscopic food by constantly filtering large volumes of seawater. More than 9,600 species are currently known worldwide, with many parts of the world still unexplored.

The new discoveries will increase the ecological importance of Mallorca channel seamounts and sea caves, say the researchers, providing a compelling argument for the Spanish government to drive protection measures. Before this study, only 16 of the 83 Mediterranean tetractinellid sponges had been recorded in the Balearic Islands.

A total of 36 tetractinellid sponge species were identified, including eight species new to science, such as Stelletta mortarium, named after the culinary grinding bowl, because of its shape; or Geodia matrix named after its tendency to accumulate all kind of different elements in its body. Two new species honour sponge scientists Dr Maria Antònia Bibiloni and Dr Joana Xavier.