Two new species of sponges (Porifera, Demospongiae) from the Aleutian Islands, Alaska

Two new demosponges, Megaciella pituitosa and Cladocroce toxifera, are described from the Aleutian Islands, fostering our contention that the region is a hotspot of poriferan biodiversity. Seven of the thirteen species of Megaciella now known worldwide occur in the Sea of Okhotsk or around the Aleutian Islands. Similarly, five of the sixteen species of Cladocroce known worldwide occur in Alaska. Megaciella pituitosa sp. nov. possesses two categories of choanosomal styles and spicules of different sizes that differentiate it from all known congeners. Cladocroce toxifera sp. nov. differs from all known congeners by possessing toxa and an ectosomal tangential arrangement of oxeas.