Glass Sponges off the Newfoundland (Northwest Atlantic): Description of a New Species of Dictyaulus (Porifera: Hexactinellida: Euplectellidae)

Three species of hexactinellid sponges: Aphrocallistes beatrix beatrix Gray, Asconema foliata (Fristedt), and Dictyaulus romani sp. n. were collected off the Flemish Cap in the Flemish Pass and from the Grand Banks off the Newfoundland (northwest Atlantic) during different surveys on board of Spanish RV Vizconde de Eza and RV Miguel Oliver. 1. Introduction The hexactinellid fauna of the northwest Atlantic is remaining poorly investigated up to now. A unique notable population of Vazella pourtalesi Schmidt was recently described from the adjacent area (the shelf of Scotia) [1], a monospecific genus previously known by few specimens from two findings in the Caribbean Sea off Florida and off Azores [2]. The present work complements data on hexactinellid fauna of the northwest Atlantic (the Newfoundland area). It is based on materials collected on groundfish bottom trawl surveys and on NEREIDA cruises. We describe a new species of Dictyaulus, a genus known for a long time by a single representative from the Indian Ocean, and recently two species from the central Pacific [3] and the north Atlantic [4] were described. 2. Material and Methods Material was collected by groundfish bottom trawl surveys by the RV Vizconde de Eza supported by the Instituto Espa？ol de Oceanografía and the European Union (methodology used is described in [5]) and from rock dredge samples on board the RV Miguel Oliver sustained by Spain’s General Secretariat of the Sea (Secretaría General del Mar) in the framework of the NEREIDA (a multidisciplinary research project). Samples were fixed in 70° ethanol. Spicules were dissociated using solution of K2Cr2O7, fresh water, and H2SO4 then washed in fresh, water, and dried. Spicules were mounted in Canada balsam and analysed (including measurements) using light microscopy. Type materials are stored in the National Museum of Natural Sciences in Madrid (Spain); other specimens are deposited in the Instituto Espa？ol de Oceanografía, Vigo (Spain); small fragments and slides for the light microscopy of all investigated specimens are treasured in the P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow (Russia). ？Taxonomy？Hexactinellida Schmidt, 1870？Hexasterophora Schulze, 1886？Hexactinosida Schrammen, 1903？Aphrocallistidae Gray, 1867？Aphrocallistes aff. beatrix beatrix Gray, 1858 Material Examined. IEO: RV Vizconde de Eza, St. FC07 L19, 25.06.2007, 46°43,62′-42,02′ N 46°19,40′-18,58′ W, depth 404？m. Description. Three small fragments of 20 × 15？mm, 15 × 10？mm, and 15 × 5？mm were studied. Remarks. This specimen does not