Dataset Information

Sponges of Western Mediterranean seamounts: new genera, new species and new records.

ABSTRACT:

Background

The seamounts Ses Olives (SO), Ausias March (AM) and Emile Baudot (EB) at the Mallorca Channel (Balearic Islands, western Mediterranean), are poorly explored areas containing rich and singular sponge communities. Previous works have shown a large heterogeneity of habitats, including rhodolith beds, rocky, gravel and sandy bottoms and steeped slopes. This diversity of habitats provides a great opportunity for improving the knowledge of the sponges from Mediterranean seamounts.

Methods

Sponges were collected during several surveys carried out by the Balearic Center of the Spanish Institute of Oceanography at the Mallorca Channel seamounts. Samples were obtained using a beam-trawl, rock dredge and remote operated vehicle. Additional samples were obtained from fishing grounds of the Balearic Islands continental shelf, using the sampling device GOC-73. Sponges were identified through the analysis of morphological and molecular characters.

Results

A total of 60 specimens were analyzed, from which we identified a total of 19 species. Three species and one genus are new to science: Foraminospongia balearica gen. nov. sp. nov., Foraminospongia minuta gen. nov. sp. nov. and Paratimea massutii sp. nov. Heteroxya cf. beauforti represents the first record of the genus Heteroxya in the Mediterranean Sea. Additionally, this is the second report of Axinella spatula and Haliclona (Soestella) fimbriata since their description. Moreover, the species Petrosia (Petrosia) raphida, Calyx cf. tufa and Lanuginella pupa are reported for the first time in the Mediterranean Sea. Petrosia (Strongylophora) vansoesti is reported here for the first time in the western Mediterranean Sea. Haliclona (S.) fimbriata is reported here for the first time in the north-western Mediterranean Sea. Hemiasterella elongata is reported here for the second time in the Mediterranean Sea. The species Melonanchora emphysema, Rhabdobaris implicata, Polymastia polytylota, Dragmatella aberrans, Phakellia ventilabrum and Pseudotrachya hystrix are reported for first time off Balearic Islands. Following the Sponge Barcoding project goals, we have sequenced the Cytochrome Oxidase subunit I (COI) and the 28S ribosomal fragment (C1-D2 domains) for Foraminospongia balearica sp. nov., Foraminospongia minuta sp. nov., H. cf. beauforti and C. cf. tufa, and the COI for Paratimea massuti sp. nov. We also provide a phylogenetic analysis to discern the systematic location of Foraminospongia gen. nov., which, in accordance to skeletal complement, is placed in the Hymerhabdiidae family. A brief biogeographical discussion is provided for all these species, with emphasis on the sponge singularity of SO, AM and the EB seamounts and the implications for their future protection.

SUBMITTER: Diaz JA

PROVIDER: S-EPMC8403479 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundLithistid demosponges, also known as rock sponges, are a polyphyletic group of sponges which are widely distributed. In the Northeast Atlantic (NEA), 17 species are known and the current knowledge on their distribution is mainly restricted to the Macaronesian islands. In the Mediterranean Sea, 14 species are recorded and generally found in marine caves.MethodsLithistids were sampled in nine NEA seamounts during the scientific expeditions Seamount 1 (1987) and Seamount 2 (1993) organized by the MNHN of Paris. Collected specimens were identified through the analyses of external and internal morphological characters using light and scanning electron microscopy, and compared with material from various museum collections as well as literature records.ResultsA total of 68 specimens were analysed and attributed to 17 species across two orders, seven families, and seven genera, representing new records of distribution. Ten of these species are new to science, viz. Neoschrammeniella inaequalis sp. nov., N. piserai sp. nov., N. pomponiae sp. nov., Discodermia arbor sp. nov., D. kellyae sp. nov., Macandrewia schusterae sp. nov., M. minima sp. nov., Exsuperantia levii sp. nov., Leiodermatium tuba sp. nov. and Siphonidium elongatus sp. nov., and are here described and illustrated. New bathymetric records were also found for D. ramifera, D. verrucosa and M. robusta. The Meteor seamount group has a higher species richness (15 species) compared to the Lusitanian seamount group (six species). The majority of the species had their distribution restricted to one seamount, and ten are only known from a single locality, but this can be a result of sample bias.DiscussionThe number of species shared between the seamounts and the Macaronesian islands is very reduced. The same pattern repeats between the NEA and Mediterranean Sea. This study demonstrates that NEA seamounts are ecosystems with a higher diversity of lithistids than previously thought, increasing the number of lithistids known to occur in the NEA and Mediterranean Sea from 26 to 36 species.