Sphaerotylus raphidophora Austin, Ott, Reiswig, Romagosa & G, 2014, n. sp.

• Main Authors: Austin, William C., Ott, Bruce S., Reiswig, Henry M., Romagosa, Paula, G, Neil
• Format: Other/Unknown Material
• Language: unknown
• Published: 2014
• Subjects: Biodiversity; Taxonomy; Animalia; Porifera; Demospongiae; Hadromerida; Polymastiidae; Sphaerotylus; Sphaerotylus raphidophora; Arctic; Antarctic; Barents Sea; Austin; Gulf of Alaska; Giacomini Seamount; Antarc*; Alaska
• Online Access: https://zenodo.org/record/6132546; https://doi.org/10.5281/zenodo.6132546

Sphaerotylus raphidophora n. sp. Figs. 12 A–D, 13 A–F Etymology. The species name, raphidophora, reflects its raphide bearing character. Material examined. Holotype: USNM 1231336, NOAA 2004 Exploring Alaska's Seamounts Expedition, Alvin Dive 4040, Giacomini Seamount, Gulf of Alaska, (56 º 25.43 ′N, 146 º 22.28 ′W), 862 m depth, Aug. 16, 2004. Description. Macroscopic features. Specimen irregular button shape about 1.6–1.7 cm in diameter by 6.9 mm (Fig. 12 A). No papillae present; however, one or more may have broken off. Colour in alcohol “yellow-brown”. Microscopic features. Skeleton composed of a palisade of megasleres, many with rounded tips protruding from the surface. Longitudal tracts of megascleres radiate out through the choanosome to end at the base of the ectosome (Fig. 12 B). Spicules. Spicule complement includes exotyles (Fig. 13 A), two classes of tylostyles (small, Fig 13 C, D), (medium, Fig. 13 E), large subtylostyles (Fig. 13 F), and raphides (Fig. 13 B). Megascleres in the ectosome include exotyles which have a granulated head ranging from stylote to tylote (Fig. 12 C, D). They are strongylote rather than stylote at the other end. Small styles to tylostyles occur in the ectosome (Fig. 13 C) while large subtylostyles form the longitudinal tracts in the choanosome (Fig. 13 D). Additional medium size tylostyles occur between the tracts (Fig. 13 E). Raphides bundled in trichodragmata (Fig. 13 B) were found in samples from four different locations in the specimen. Holotype USNM 1231336 Remarks. We compared spicules in our species with those in Sphaerotylus species listed in the World Porifera Database (van Soest et al. 2012) (Table 9). Spicule type. Austin et al. Boury-Esnault Koltun Kirkpatrick Hentschel this paper 2002 1966 1908 1914 raphidophora capitatus schoenus capitatus vanhoeffeni s. Alaska Barents Sea Arctic Antarctic Antarctic Exotyles 568–1374 650–950 600–1250 760 504–1080 stylote-tylote tylote subtylote-tylote spherulote club granules granules granules granules granules Lg.subtylostyles ...