taxonID	type	description	language	source
EF19F029890BFFE4FF28FCC1E3339E72.taxon	materials_examined	Type species: Cornulum textile Carter, 1876 (type by monotypy)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890BFFE2FF28FC7CE1C49A3E.taxon	materials_examined	Material examined. Holotype: ZSM 20150381, collected by Brian Knoth with a research survey bottom trawl from the FV Ocean Explorer; 18 June 2012, 226 m depth, 28.2 km south of Yunaska Island, eastern Aleutian Islands, North Pacific Ocean (52 ° 17.3400 ' N, 170 ° 48.2340 ' W). Water temperature = 4.2 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890BFFE2FF28FC7CE1C49A3E.taxon	description	Description. Habitus: Globular, pale yellow colored sponge, 9 – 11 cm in diameter (Fig. 2 A). The sponge is attached firmly to a fragmented pebble. The ectosome is a thick parchment-like membrane and the surface is covered with numerous fistules (Fig. 2 B). These fistules are hollow, up to 12 mm high and 6 mm wide. The bottom of the fistule opens into the choanosome but they are closed on top. Skeletal structure: The ectosome is fastened to the choanosome by polyspicular tracts which fan out into the ectosome and stick to the ectosome when it is detached (Fig. 2 B) and, are then visible to the unaided eye. These polyspicular tracts are 4 – 6 mm long, with a diameter of 800 – 1100 µm, consist of choanosomal styles and are irregularly spaced. In some places up to 6 spicule tracts originate from the ectosome with no particular distance and in other places there are 4 – 5 mm or more in between single tracts. The ectosomal membrane is somewhat transparent, especially on the bottom side of the sponge where black sediment particles are visible within the sponge. The ectosome contains mainly tylotes except in places where choanosomal polyspicular tracts merge into the ectosome, and here ectosomal tylotes and choanosomal styles are observed together. Ectosomal tylotes are arranged paratangentially with the axis mostly horizontal but, within this plane facing in all directions. The ectosomal membrane with the attached spicule tracts has a high spicule density and is very resilient, while spicule density in the choanosome is much lower and therefore the choanosome is soft and easily torn. Spicule arrangement in the choanosome is halichondroid, only short and vague tracts are recognisable. Spicules: Spicules are entirely smooth tylotes, 340 – 920 x 12 – 18 µm (Fig. 2 C), in the ectosomal membrane, choanosomal smooth styles are 956 – 1180 x 18 – 21 µm (Fig. 2 C). Microscleres are palmate isochelas measuring 52 – 67 µm (Fig. 2 D) and two size categories of toxa: thick toxa, 112 – 135 x 9 – 11 µm (Fig. 2 E) and thin toxa, 180 – 210 µm (Fig. 2 F).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890BFFE2FF28FC7CE1C49A3E.taxon	discussion	Discussion. Entirely smooth tylotes would be a new characteristic within the genus Cornulum but do occur in Tedaniophorbas de Laubenfels, 1936. We excluded the possibility of the new species belonging to the monotypic Tedaniophorbas because it simply differs in too many characters. Tedaniophorbas is non-fistular and has a welldeveloped skeleton of spongin fibers without coring or echinating spicules, megascleres are smooth tylotes only, and microscleres consist of isochelas. Contrastingly, the species described here is fistular, lacks a spongin skeleton without inclusions, and additionally has choanosomal styles and different categories of toxas. Accordingly, we assign the new species to Cornulum since it more closely conforms to that genus and requires only the single modification to allow for smooth tylotes. The WPD recognizes ten valid species in the genus Cornulum. Cornulum are massive or encrusting sponges of the family Acarnidae with erect fistules or pronounced pore areas, with apically spined tylotes or strongyles forming both tangential and plumo-reticulate choanosomal skeletons, sometimes together with choanosomal styles or aniso-strongyles (Hooper, 2002 a). We compare the new species with four species known from the North Pacific and the North Atlantic Oceans. Comparison of spicule categories and their dimensions are given in Table 1. The remaining six species are described from the Antarctic, Indonesia, the Philippines, New Caledonia, the Caribbean and Brazil and were not considered given obvious zoogeographic reasons. Cornulum globosum n. sp. differs from the species compared with in the following characters: C. clathriata: North Atlantic Ocean, Arctic Ocean, and Northwest Pacific Ocean (Commander Islands in Russia, western Bering Sea, and the central Aleutian Islands). Bush- or fan-shaped, ectosomal tylotes are shorter and thinner, spherical isochelae that are smaller, and toxa of different size categories. C. enteromorphoides: North Atlantic Ocean (around Greenland). A cylindrical sponge, “ light with a tint of yellow ” (Fristedt, 1887, p. 448), megascleres are microspined, both categories being shorter, two categories of isochelae, no toxa. C. textile: North Atlantic Ocean and Northwest Pacific Ocean (Sea of Okhotsk). A lobate to digitate sponge, ectosomal tylotes have microspined ends and are shorter, choanosomal styles may have microspined bases and are shorter, isochelae are smaller, no toxa. C. tubiforme Northwest Pacific Ocean (Sea of Okhotsk, Sea of Japan, and East Sea). A tube-shaped sponge with oxeote ectosomal spicules which are shorter and thinner, no choanosomal styles, smaller isochelae, and only one category of toxa. C. globosum is somewhat unusual within the genus in having smooth tylotes but Hooper (2002 a) mentions that C. textile also has smooth microspined tylotes and writes (p. 419) ” … all members of Cornulum share the microspined condition of megascleres (occasionally verging towards entirely smooth), …. ”, so smooth ectosomal spicules have already been recorded for the genus.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890BFFE2FF28FC7CE1C49A3E.taxon	etymology	Etymology. From the Latin globosum — referring to the sponge’s globular habitus. + Measurements are from Hooper (2002 a). ++ The WPD lists the valid species name as C. tubiforme Burton, 1935. Burton himself however, offers two names: in the list of species (p. 63) it appears as “ 43. C. tubiformis n. sp. ” but then when describing the species (p. 73) he indicates as “ Cornulum tubiformes sp. n. ”	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890DFFE2FF28F8B7E3CA9ACD.taxon	materials_examined	Type species: Amphilectus pilosus Ridley & Dendy, 1886 (by original designation)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890CFFE0FF28FF5CE4349AD4.taxon	materials_examined	Material examined. Holotype: ZSM 20150382, collected by Jay Orr with a research survey bottom trawl (haul # 166) from the FV Ocean Explorer; 17 July 2012, 91 m depth, 2.1 km north of western Kiska Island, western Aleutian Islands, Bering Sea (51 ° 59.5740 ' N, 177 ° 23.0100 ' E). Water temperature = 4.3 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890CFFE0FF28FF5CE4349AD4.taxon	description	Description. Habitus: This is a small, brown-colored sponge of firm, only slightly elastic consistency. It has an almost circular outline where several lobes radiate from a center (Fig. 3 A). The lobes are 0.5 – 2 cm in thickness and up to 2 cm long, starting from a common center, 3.5 x 4.4 x 5.3 cm. Lobes may be partially fused. The surface is hispid, due to projecting spicules of choanosomal spicule tracts (Fig. 3 B). Skeletal structure: The ectosome is a thin membrane and contains scattered anisotylotes with microspined bases and microscleres (Fig. 3 C). In the choanosome, plumose tracts, cored by smooth styles (Fig. 3 D) and echinated by acanthostyles (Fig. 3 B & E), ascend to the surface with the end of the tracts as the cause of the hispid surface. Spicules: Ectosomal anisotylotes have microspined ends, one end more inflated, the other often looking broken but, upon closer examination is complete due to micro-spination, 355 – 508 x 4 – 6 µm (Fig. 3 F). Coring the tracts are single, long smooth styles, mostly broken in spicule preparations, 1056 – 1645 x 19 – 32 µm (Fig. 3 E). Choanosomal styles, varying from completely smooth or with slightly microspined bases only, to microspined areas at both ends of the style, 735 – 928 x 42 – 55 µm (Fig. 3 D), acanthostyles, 440 – 710 x 42 – 53 µm (Fig. 4 A). Microscleres are toxa in two categories: long, thin toxa, 130 – 720 µm (Fig. 4 C) and short, thicker toxa, 29 – 47 µm (Fig. 4 B) and palmate isochelae, 22 – 47 µm (Fig. 4 D).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890CFFE0FF28FF5CE4349AD4.taxon	discussion	Discussion. The WPD currently recognises 14 species of Megaciella including two species previously described from the Aleutian Island Archipelago region (Lehnert et al., 2006 b; Lehnert & Stone, 2014 b). Megaciella are non-fistular branching, lobate, flabellate, or encrusting sponges of the family Acarnidae with a confused choanosomal skeleton divided into primary ascending multispicular tracts and secondary interconnecting uni- and bispicular tracts cored by basally spined styles, with or without echinating acanthostyles (Hooper, 2002 a). We compare with 9 species co-occurring in the North Pacific Ocean, including one from off the Californian Coast, another from off the Pacific Coast of Mexico, and with the second new Megaciella, described below (Table 2). The two species we describe here are the only Megaciella with a third category of thin styles. Megaciella lobata n. sp. differs from the species compared with in the following characters: M. anisochelae: Northwest Pacific Ocean (central Aleutian Islands). A stalked cluster of tubes with shorter and thicker styles, no acanthostyles, two categories of isochelae (both smaller), anisochelae, but no toxa or echinating spicules. M. fragilis: Northwest Pacific Ocean and Sea of Okhotsk. A dactylate or lobate sponge, light yellow in color, with shorter tylotes, shorter and thinner styles, no acanthostyles, smaller isochelae, both categories of toxa are shorter. M. microtoxa: Northeast Pacific Ocean (Coast of Mexico). A massive sponge with shorter tylotes, choanosome with acanthostyles only, shorter isochelae, and one category of toxa that are intermediate in length to those of M. lobata. M. ochotensis: Northwest Pacific Ocean and Sea of Okhotsk. A lobate to dactylate sponge with shorter tylotes, choanosome with acanthostyles only, shorter isochelae, and only one category of toxa. M. pituitosa: Northwest Pacific Ocean (Aleutian Islands). A stalked and fan-shaped sponge with shorter tylotes, shorter and thinner styles, shorter and thinner acanthostyles, smaller isochelae, and smooth toxa of different size categories. M. spirinae: Northwest Pacific Ocean, Sea of Okhotsk, and central Aleutian Islands. An irregularly massivelobate sponge with smaller tylotes, choanosome with acanthostyles only which are much smaller, only one category of choanosomal styles, only one category of toxa. M. toxispinosa: Northeast Pacific Ocean (Mexican Tropical Pacific). A thinly encrusting sponge with shorter tylotes, choanosome with acanthostyles only, two categories of isochelae, shorter categories of toxa. M. zenkevitchi: Northwest Pacific Ocean and Sea of Okhotsk. A sponge with shorter but thicker tylotes, choanosomal styles are shorter and thinner, small toxa are longer. M. triangulata n. sp.: Northwest Pacific Ocean (Aleutian Islands). A stalked and funnel-shaped sponge with shorter but thicker tylotes, shorter and thinner styles and acanthostyles, two categories of isochelae (both smaller), microspined toxa of different sizes, small category of anisochelas.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890CFFE0FF28FF5CE4349AD4.taxon	etymology	Etymology. From the latin lobatus — referring to the sponge’s lobate habitus.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890EFFEDFF28FAAAE1A89EB0.taxon	materials_examined	Material examined. Holotype ZSM 20150383 and paratype ZSM 20150384 collected by Jim Stark with a research survey bottom trawl (haul # 180) from the FV Ocean Explorer; 24 July 2012, 141 m depth, Buldir Reef, western Aleutian Islands, North Pacific Ocean (52 ° 03.4140 ' N, 176 ° 25.0800 ' E). Water temperature = 4.1 ° C. Complete specimens in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890EFFEDFF28FAAAE1A89EB0.taxon	description	Description. Habitus: Both specimens are golden brown in color on wiry stalks. The holotype (larger specimen) is 17 cm in height and 11 cm in maximum width (Fig. 5 A). The stalk of the holotype is 1.5 – 2 cm thick and expands after 5.5 cm into a massive triangle with sides almost symmetrical (11.5, 11 and 12 cm long) and 2.5 – 3 cm in thickness. The paratype (smaller specimen) attains 14 cm in height, the stalk is 0.8 cm at the base and more irregularly shaped, it widens to 1.9 cm in diameter where it expands into a small massive triangle, the sides 4, 4.5 and 5 cm long with a thickness of 1.5 cm (Fig. 5 A). The stalk has a smooth surface without recognisable apertures; the triangle bears numerous small pores, flush with the surface and 1 – 2 mm in diameter. The triangle part of the sponge is much softer and more elastic than the stalk due to a higher spicule density in the stalk. Skeletal structure: The choanosome consists of an irregular reticulation of paucispicular tracts with many microscleres in between (Figs. 5 B & C). Acanthostyles are irregularly scattered in the choanosome. The thin styles are usually coring the tracts. Ectosomal tylotes are arranged paratangentially in bundles (Fig. 5 D) or in short tracts facing in different directions. Towards the stalk the abundance and density of these tylotes increases, recognisable in a smoother surface. Spicules: Ectosomal tylotes are fusiform, tyles have a straight, microspined end and measure, 182 – 346 x 8 – 11 µm (Fig. 5 E), choanosomal thick styles are smooth, slightly bent, 295 – 546 x 18 – 35 µm (Fig. 5 F), thin styles, 335 – 452 x 8 - 11 µm (Fig. 5 F), acanthostyles, 340 – 435 x 22 - 25 µm (Fig. 6 A). Microscleres are two categories of toxa, large category spined at the ends and with a U-turn in the center, 290 – 425 µm (Fig. 6 B), thicker than the small category which measures 65 – 185 µm and is spined all over (Fig. 6 C) and two categories of palmate isochelae, the large category with pointed ends on top and bottom, 13 – 18 µm (Fig. 6 D), small category without pointed ends, 7 – 10 µm (Fig. 6 E) and, finally, a tiny category of anisochelae, 5 – 7 µm (Fig. 6 F).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890EFFEDFF28FAAAE1A89EB0.taxon	discussion	Discussion. Again, we compare this new Megaciella with the nine other species co-occurring in the North Pacific Ocean (Table 2). M. triangulata n. sp. differs from these species in the following characters: M. anisochelae: A stalked cluster of tubes with no acanthostyles or toxa. M. fragilis: A dactylate or lobate sponge, light yellow in color, with shorter and thinner tylotes, thinner styles, no acanthostyles, only one category of isochelae, and toxa of different sizes. TABLE 2. Spicule categories and measurements of Megaciella from the North Pacific Ocean. All measurements are in µm. species tylotes styles echinating spicules isochelae toxa other anisochela Lehnert et microspined ends, smooth, 490 – 615 x none large, 13 – 17, small, 6 – 8 none anisochelas, 4 – 6, 2006 c 245 – 380 x 4 – 9 18 – 22 fragilis (Koltun, microspined ends, smooth, 291 – 364 x none 14 – 17 large, 124 – 218 x 2, small, 21 – none) 176 – 228 x 6 – 8 12 – 18 35 x 1 microtoxa microspined ends, acantho-, 360 – 540 x acanthostyles, 85 – 215 12.5 – 15 50 – 140 none Dickinson, 1945) + 190 – 250 x 2.5 – 5 17.525 x 2.5 – 7.5 ochotensis (Koltun, “ fusiform tornotes ”, acantho-, 168 – 252 x none 25 – 32 84 – 134 none) 151 – 220 x 5 – 9 11 – 14 pituitosa Lehnert & microspined ends, smooth, 460 – 630 x acanthostyles, 140 – 15 – 20 large, 120 – 300, small, 40 – 87 x none Stone, 2014 b 144 – 310 x 4 – 6 26 – 30 145 x 8 – 10 2 – 3 spirinae (Koltun, microspined ends, acantho-, 166 – 213 x none 23 – 35 136 - 200 x 9 none) 166 – 208 x 3 – 4 10 – 13 toxispinosa Aguilar- microspined ends, acantho-, 150 – 315 x acanthostyles, 55 – 105 two categories; reduced alae, large, 35 – 60, small none Camacho et al., 2014 160 – 215 x 2.5 2.5 – - 5 x 2.5 – 3.5 12.5 – 15, alae fused with shaft, (microspined, “ oxhorn- 12.5 – 17.5 shaped ”), 3 – 10 zenkevitchi (Koltun, microspined ends, acantho., 405 – 478 x apically spined styles, 21 – 25 large, 178 – 364, small, 75 – 92 none) 208 – 343 x 7 – 10 33 – 42 364 – 475 x 10 – 12 lobata n. sp. microspined ends, smooth & acanthostyles, 440 – 22 – 27 two categories; large, 130 – 720 large smooth styles, 355 – 508 x 4 – 6 microspined 735 – 928 710 x 42 – 55 & small, 29 – 47 1056 – 1645 x 19 – 32 x 42 – 55 triangulata n. sp. fusiform tylotes, smooth, 295 – 516 x acanthostyles, 340 – two categories; large, 13 – 18 & two categories; microspined thin styles, 335 – 452 x microspined ends, 18 – 35 435 x 22 – 25 small, 7 – 10 (different shapes?) all over, weakly bent, thin 65 – 6 – 10, anisochelas, 5 – 7 182 – 346 x 8 – 11 185 microspined ends, strongly bent, thicker, 290 – 428 after Aguilar-Camacho et al. (2014) M. microtoxa: A massive sponge with shorter and thinner tylotes, a choanosome with acanthostyles only, only one category of isochelae, and only one category of toxa. M. ochotensis: A lobate to dactylate sponge with shorter and thinner tylotes, choanosome with acanthostyles only, only one category of isochelae, and only one category of toxa. M. pituitosa: Also stalked but fan-shaped, with thinner tylotes, shorter and thinner acanthostyles, only one category of isochelae, and smooth toxa. M. spirinae: An irregularly massive-lobate sponge with smaller tylotes, choanosome with acanthostyles only which are smaller, only one category of choanosomal styles that are larger, and only one category of toxa. M. toxispinosa: A thinly encrusting sponge with shorter and much thinner tylotes, choanosome with acanthostyles only, different size categories of isochelae, and shorter categories of toxa. M. zenkevitchi: A sponge with differently shaped tylotes, categories of choanosomal styles differ in shape and size, only one category of isochelae, and different size categories of toxa. M. lobata n. sp.: A lobate sponge with longer and thinner tylotes, longer and thicker styles and acanthostyles, one category of isochelae that are larger, and smooth toxa of different size categories.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029890EFFEDFF28FAAAE1A89EB0.taxon	etymology	Etymology. from the Latin triangulata — triangular, referring to the triangular shape of the main body of the sponge on top of the stalk.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298902FFEDFF28FB48E39499CA.taxon	materials_examined	Type species: Artemisina suberitoides Vosmaer, 1885 (type by monotypy)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298902FFEBFF28FAE4E4319968.taxon	materials_examined	Material examined. Holotype: ZSM 20150385, collected by Jim Stark with a research survey bottom trawl (haul # 162) from the FV Ocean Explorer; 16 July 2012, 262 m depth, 11.1 km southeast of Vega Point, south Kiska Island, western Aleutian Islands, North Pacific Ocean (51 ° 46.3740 ' N, 177 ° 27.4560 ' E). Water temperature = 4.1 ° C. Paratype: ZSM 20150386, collected by Jim Stark with a research bottom trawl (haul # 193) from the FV Ocean Explorer on 27 July 2012, 228 m depth, 30.6 km SSE of Fox Beach Point, Shemya Island, Semichi Islands, western Aleutian Islands, North Pacific Ocean (52 ° 26.5920 ' N, 174 ° 18.1740 ' E). Water temperature = 3.7 ° C. Complete specimens in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298902FFEBFF28FAE4E4319968.taxon	description	Description. Habitus: The holotype (ZSM 20150385, Fig. 7 A) was noted as extremely slimy and exuded a very thick mucous-like substance. It is light brown, starts from a narrow, short, almost circular, stiff stalk, 2.1 cm in diameter, 1.6 cm high. The sponge then becomes soft and elastic but, still resilient and widens at a height of 8.5 cm to 5 cm with a thickness of 1 cm. Several lobes grow independently from a central part, the largest lobe 9.5 x 4 x 1 cm. The paratype (ZSM 20150386, Fig. 7 B) is a golden-brown, club-shaped sponge, possibly a juvenile specimen, becoming stalked and branching later. Attached at the narrow end to a well-rounded pebble, gradually widening from 1.5 cm to a maximum diameter of 4.5 cm, reaching a height of 14.5 cm with a thickness of 1.3 cm. The surface of both specimens is corrugated with circular oscules, flush with the surface, 1.5 – 3 mm in diameter are scattered over the surface except for the stalk of the larger specimen. Skeletal structure and spicules: The choanosome is a reticulation of styles, 560 – 620 x 30 – 35 µm (Fig. 7 C). The ectosome consists of a thin organic membrane with densely packed styles to subtylostyles with microspined heads, sometimes with one prominent tooth, 260 – 340 x 6 – 7 µm (Fig. 7 D). Microscleres are small, very thin, palmate isochelae, 5 – 9 µm (Fig. 7 E) and toxa with microspined ends, 280 – 540 µm (Fig. 7 F).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298902FFEBFF28FAE4E4319968.taxon	discussion	Discussion. The WPD recognizes 18 valid species of Artemisina. Artemisina are massive, cushion-shaped, bulbous, clavulate, tubular, digitate, or flabellate sponges of the family Microcionidae. They lack a distinctive choanosomal skeleton or definite spongin fibres and echinating spicules, and have a nearly radial ectosomal skeleton (Hooper, 2002 c). We compare Artemisina clavata n. sp. with eight species occurring from the North Pacific and North Atlantic Oceans (Table 3) and with the second new Artemisina described below. The remaining ten species are not taken into consideration for zoogeographic reasons. Artemisina clavata n. sp. differs from these species in the following characters: A. amlia: Northwest Pacific Ocean (central Aleutian Islands). A stalked, subhemispherical or conical sponge with longer and thicker ectosomal styles, shorter and thinner choanosmal styles, smooth toxa, and no microspined toxa. A. apollinis: Southern Ocean, North Atlantic Ocean, and southern Indian Ocean. A massive to funnel-shaped sponge with longer ectosomal styles, thinner choanosomal styles, two categories of toxa, and larger isochelae. A. archegona: Northeast Pacific Ocean (California to British Columbia). A thinly encrusting sponge, bright orange color in life, white in ethanol, with thinner ectosomal styles, shorter and thinner choanosomal styles, a special category of toxiform oxeas, smooth toxa only, and longer isochelae. A. arcigera: Arctic Ocean, North Atlantic Ocean, and Northwest Pacific Ocean (central Aleutian Islands. A massive to spherical or stalked and tube-shaped (central Aleutian Islands) sponge, only 5.5 cm high, with longer and thicker ectosomal styles, much thinner choanosomal styles, shorter microspined toxa, and longer isochelae. A. erecta: Northeast Atlantic Ocean (Azores, Canaries, Madeira). A small (11 mm x 5 mm x 3 mm), white colored sponge with longer ectosomal styles, longer but thinner choanosmal styles, shorter microspined toxa, and longer isochelae. A. stipitata: Northwest Pacific Ocean (Sea of Okhotsk and central Aleutian Islands). A massive to spherical or flabellate (central Aleutian islands) sponge with thicker ectosomal styles, shorter and thinner choanosomal styles, no toxa, and longer isochelae. A. transiens: Northeast Atlantic Ocean. A stalked, white-colored sponge with longer ectosomal styles with microspined ends, choanosomal styles not different from ectosomal styles, smooth toxa but no microspined toxa, and much longer isochelae. A. flabellata n. sp.: Aleutian Islands. A fan-shaped sponge with longer and thicker ectosomal styles, longer choanosomal styles, smooth toxa but no microspined toxa, cleistochelae, and an additional category of acanthostyles.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298902FFEBFF28FAE4E4319968.taxon	etymology	Etymology. from the Latin clava — club, referring to the club-shaped growth.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298904FFF7FF28FB04E4759FBD.taxon	materials_examined	Material examined. Holotype: ZSM 20150387, collected by Jay Orr with a research survey bottom trawl (haul # 135) from the FV Ocean Explorer; 11 July 2012, 99 m depth, Petrel Bank, central Aleutian Islands, Bering Sea (52 ° 15.9960 ' N, 179 ° 54.0060 ' E). Water temperature = 4.3 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298904FFF7FF28FB04E4759FBD.taxon	description	Description. Habitus: Large, light brown to gold colored, fan-shaped to flabellate sponge, starting from an almost circular base with a maximum diameter of 7 cm and a height of 26.5 cm, the upper rim approximates a quarter-circle, 25.8 cm in width (Fig. 8 A). The thickness of the blade is quite variable, the thickest part is 9 cm while other parts are less than 1 cm in thickness. There is a hole in the center of the blade, possibly from tissue necrosis (Fig. 8 B). No oscules are visible. The consistency of the base is hard and inelastic, softer and more elastic but, still resilient, towards the top. Skeletal structure: The ectosome is a relatively thick veneer of densely packed thin ectosomal styles primarily in a tangential arrangement, single bundles of ectosomal styles may stand perpendicular to the surface and consequently the thickness varies between 200 and 700 µm. The choanosome is halichondroid and consists of vague tracts with many spicules in between. Plumose tracts are irregular and there are many spicules in between. Spicules: are thick choanosomal styles, finely spined apically, 648 – 1630 x 25 – 33 µm (Figs. 8 C & E), occasionally strongylote or weakly microspined all over, apically spined ectosomal styles, 453 – 1152 x 9 – 16 µm (Figs. 8 D & E), small acanthostyles, 157 – 248 x 15 – 18 µm (Fig. 8 F), cleistochelae with a peculiar central plate on the shaft and the alae fused or open with a small gap, 13 – 18 µm (Figs. 9 A & B), thin, smooth toxa, 90 – 1150 µm (Fig. 9 C).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298904FFF7FF28FB04E4759FBD.taxon	discussion	Discussion. The skin-like ectosome and halichondroid choanosome warrant assignment in the genus Artemisina. Again we compare Artemisina flabellata n. sp. with eight species occurring from the North Pacific and North Atlantic Oceans (Table 3) and with the other new Artemisina described above. Artemisina flabellata n. sp. differs from these species in possessing cleistochelae and the following characters: A. amlia: A stalked, subhemispherical or conical sponge with shorter ectosomal styles, shorter choanosomal styles, and shorter smooth toxa. A. apollinis: A massive to funnel-shaped sponge with shorter and thinner ectosomal styles, shorter choanosomal styles, and two categories of toxa. A. archegona: A thinly encrusting sponge, bright orange color in life, white in ethanol, with shorter and much thinner ectosomal styles, and shorter and thinner choanosomal styles. A. arcigera: A massive to spherical or stalked and tube-shaped (central Aleutian Islands) sponge, only 5.5 cm high, with shorter ectosomal styles, shorter and much thinner choanosomal styles, and microspined toxa but no smooth toxa. A. erecta: A small (11 mm x 5 mm x 3 mm), white colored sponge with shorter and thinner ectosomal styles, shorter choanosmal styles, and microspined toxa but no smooth toxa. species ectosomal styles choanosomal styles smooth toxa microspined toxa isochelae other amlia Lehnert et al., 330 – 550 x 9 – 11 400 – 520 x 20 – 25 110 – 170 none 10 – 13 none 2006 a apollinis (Ridley & 290 – 457 x 5 – 9 500 – 842 x 13 – 21 85 – 280 291 – 468 14 – 18 none Dendy, 1886) archegona Ristau, 120 – 340 x 2.5 185 – 240 x 7 – 20 105 – 520 x none 18 – 21 toxiform oxeas, 450 – 800 1978 0.5 – 1.0 x 3 – 6 Topsent did not provide measurements in the text. Sizes of isochelae were measured by us from Topsent´s plate IX, Fig. 7. A. stipitata: Massive to spherical or flabellate (central Aleutian islands) sponge with shorter ectosomal styles, shorter choanosomal styles, and no toxa. A. transiens: A stalked, white-colored sponge with shorter ectosomal styles, choanosomal styles not different from ectosomal styles, and shorter smooth toxa. A. clavata n. sp.: A club-shaped sponge with shorter and thinner ectosomal styles, shorter choanosomal styles, and microspined toxa but no smooth toxa. Artemisina flabellata n. sp. is the only species of Artemisina discussed that has a third category of megasclere in addition to the ectosomal and choanosomal styles; the latter two styles being the longest within the genus. These acanthostyles were found irregularly distributed, singly or in groups, in sections of the choanosome. It could be discussed if these are really proper to the sponge. The irregular distribution might be an argument for a foreign inclusion but, as they were found quite often in different sections we think it far more probable they are proper to the sponge. Validity of this new species is independent from the presence of these acanthostyles as there are three more unique characters which separate A. flabellata from all other congeners: It has two unusually long categories of styles and peculiar cleistochelae which separate this species from all others.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298904FFF7FF28FB04E4759FBD.taxon	etymology	Etymology. from the Latin flabellum — fan, referring to the habitus of this sponge.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298918FFF7FF28FC4DE35E9EF6.taxon	materials_examined	Type species: Histodermion dividuum Topsent, 1927 (by monotypy)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298918FFF4FF28FBFFE3A89C55.taxon	materials_examined	Material examined. Holotype (ZSM 20150388) and paratype (ZSM 20150389), collected by Brian Knoth with a research survey bottom trawl (haul # 15) from the FV Ocean Explorer; 13 June 2012, 265 m depth, 11 km west of Cape Kigushimkada, Umnak Island, eastern Aleutian Islands, Bering Sea (53 ° 07.0560 ' N, 168 ° 58.4400 ' W). Water temperature = 3.7 ° C. Complete specimens in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298918FFF4FF28FBFFE3A89C55.taxon	description	Description. Habitus: A globular, golden-yellow sponge with a surface covered with thin, flattened fistules. Two specimens were collected, the larger (holotype) measures 6 – 6.4 cm in diameter and 4.8 cm in height, the smaller (paratype) with a maximum diameter of 4.4 cm attains a height of 2.3 cm (Fig. 10 A). Long fistules are 4 – 7 cm in length, 1.5 – 3 mm in diameter and are separated at distances of about 2 – 3 mm. Shorter fistules are recognisable in between long fistules starting from below 1 mm with intermediate lengths up to long fistules. We assume the growth of new fistules between existing ones as the surface of the sponge is spreading during growth. The largest fistules sometimes branch or might be the result of coalescing fistules. Consistency is resilient and elastic. Skeletal structure: Typical of the genus the sponge is hollow, bladder-like with a thick, parchment-like ectosomal membrane. The ectosomal skin is packed with isochelae (Fig. 10 B) and tornotes (Fig. 10 C) without orientation. The choanosome consists of an irregular reticulation of vague tracts (Fig. 10 D) and single spicules where all spicule categories of this species may occur. Spicules: Ectosomal (aniso-) tornotes are 415 – 622 x 8 – 11 µm (Figs. 11 A & B), choanosomal acanthostyles are 291 – 596 x 19 – 34 µm (Figs. 11 A & B). Microscleres are robust, arcuate isochelae, 38 – 46 µm (Fig. 11 C).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298918FFF4FF28FBFFE3A89C55.taxon	discussion	Discussion. Assignment to the genus Coelosphaera is without doubt because this is a hollow sponge with a parchment-like skin possessing fistules. As spiculation includes acanthostyles the subgenus Histodermion is the only option available. This is the first record of a species from the subgenus Histodermion from the Indo-Pacific region. The WPD lists only two species for the subgenus Histodermion: Coelosphaera (Histodermion) cryosi (Boury-Esnault, Pansini & Uriz, 1994) and C. (H.) dividuum (Topsent, 1927). C. (H.) cryosi is known only from the Mediterranean Sea and is much smaller (5 x 2 mm), has a different color (white in preservative), has shorter and thinner acanthostyles, has two categories of isochelae and two size categories of sigmas. C. (H.) dividuum is known only from the Azores in the North Atlantic Ocean and is an encrusting, soft and fragile species. Ectosomal tylotes to strongylotes are centrotylote and generally longer, acanthostyles are longer and thinner, and arcuate isochelae are of a broader size range.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298918FFF4FF28FBFFE3A89C55.taxon	etymology	Etymology. named after the type locality near Cape Kigushimkada.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891BFFF4FF28F8F9E30D9A9A.taxon	materials_examined	Type species: Stelodoryx procera Topsent, 1904 (by monotypy)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891AFFF1FF28F8D5E46C9F75.taxon	materials_examined	Material examined. Holotype: ZSM 20150390, collected by Jim Stark with a research survey bottom trawl (haul # 216) from the FV Ocean Explorer; 2 August 2012, 127 m depth, Stalemate Bank, western Aleutian Islands, North Pacific Ocean (52 ° 59.0760 ' N, 170 ° 55.5780 ' E). Water temperature = 3.7 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891AFFF1FF28F8D5E46C9F75.taxon	description	Description. Habitus: Massively encrusting or possibly standing upright, golden brown colored sponge, approximately 19.5 x 23 x 3.5 – 4.3 cm (Fig. 12 A). The sponge was probably attached to pebbles and was noted as incredibly mucous laden. In ethanol it is still thickly covered with mucus which comes off in long sticky strands. The consistency is firm and only slightly elastic but the sponge breaks into pieces under its own weight when handled. The surface is rugose and uneven and there are different surface patterns in different areas (Figs. 12 A & B). Skeletal structure: The ectosome consists of a single row of tylote bundles, 300 – 550 µm in diameter, starting in the interior from a narrow base, fanning out towards the surface (Figs. 12 C & D). The choanosome is a reticulation of single acanthostyles with many thin sigmas and isochelae in between (Figs. 12 C & E). Spicules: Ectosomal tylotes have unequal, microspined ends, 205 – 252 x 8 – 10 µm (Fig. 12 F, Figs. 13 A & B), choanosomal acanthostyles, 395 – 450 x 11 – 29 µm (Fig. 13 A), polydentate isochelae, 45 – 67 µm (Fig. 13 C), thin sigmas, 13 – 18 µm (Figs. 13 B & C).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891AFFF1FF28F8D5E46C9F75.taxon	discussion	Discussion. The WPD recognizes 14 valid species of Stelodoryx. Stelodoryx are stalked, lobate, massive, or encrusting sponges resembling Myxilla species in most respects, except they have a reticulate skeleton, a full complement of megascleres and polydentate anchorate isochelae (Van Soest, 2002). We compare Stelodoryx mucosa n. sp. with the eight species of Stelodoryx recorded from the North Pacific and the North Atlantic Oceans and with S. siphofuscus n. sp. described below (Table 5). S. mucosa differs from these species in the following characters: S. flabellata: North Atlantic and Arctic Oceans. A funnel-shaped sponge, 15 cm in height, with longer but thinner ectosomal tylotes which are smooth, somewhat shorter and thinner choanosomal acanthostyles, and no sigmas. S. lissostyla: North Pacific Ocean (Sea of Japan and East Sea). A sponge with smooth ectosomal tylotes which are longer but thinner, mostly smooth choanosomal styles which are shorter and thinner, two categories of isochelae, both shorter, and no sigmas. S. oxeata: North Pacific Ocean (Aleutian Islands). A stalked sponge with a ridged surface or massively encrusting with a smooth surface, greenish yellow in color, choanosomal oxeas with microspined ends, and three categories of isochelae. This is the only other species of Stelodoryx in the comparison group that has sigmas as microscleres besides S. mucosa n. sp., but the sigmas are centrotylyte rather than fine and smaller. S. pectinata: North Atlantic Ocean (Azores Canaries Madeira). A sponge with smooth ectosomal tylotes which are longer and thinner, two categories of isochelae, and no sigmas. species ectosomal tornotes choanosomal styles isochelae other	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891AFFF1FF28F8D5E46C9F75.taxon	description	Measurements from Topsent, 1892 (Topsent, 1890 provided no measurements). Measurements from Koltun, 1958. S. pluridentata: North and South Atlantic Ocean. A stiff, yellowish orange to brown colored sponge with smooth choanosomal styles, larger isochelae, and no sigmas. S. procera: North Atlantic Ocean (Azores, Canaries, Madeira). A sponge with smooth ectosomal tylotes which are thinner, two categories of smooth choanosomal styles, and no sigmas. S. toporoki: North Pacific Ocean (Sea of Okhotsk and central Aleutian Islands) and Arctic Ocean. A stalked funnel-shaped sponge with mostly smooth and much longer choanosomal styles, two categories of isochelae of different size categories, and no sigmas. S. vitiazi: North Pacific Ocean (Sea of Okhotsk, western Bering Sea and central Aleutian Islands). A tubeshaped or irregularly cylindrical sponge with thinner ectosomal tylotes, smaller isochelae, and no sigmas. S. siphofuscus n. sp.: A dark brown, stalked, tube-shaped sponge, with longer ectosomal tornotes that are not microspined, smooth choanosomal styles, microscleres consisting of two categories of isochelae, none of which correspond in size to those of S. mucosa, and lacking sigmas.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891AFFF1FF28F8D5E46C9F75.taxon	etymology	Etymology. named after the excessive production of mucus observed in this species.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891EFFFEFF28FD7FE5519F0D.taxon	materials_examined	Material examined. Holotype: ZSM 20150391, collected by Ned Laman with a research survey bottom trawl (haul # 2) from the FV Alaska Provider; 29 May 2013, 144 m depth, 2.3 km ESE of Concord Point, Chuginadak Island, Islands of Four Mountains, Samalga Pass, North Pacific Ocean (52 ° 46.3500 ' N, 169 ° 40.0200 ' W). Water temperature = 4.2 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891EFFFEFF28FD7FE5519F0D.taxon	description	Description. Habitus: The sponge is a stalked, dark brown tube, reaching a height of 23 cm and a maximum diameter of 3.4 cm (Fig. 14 A). The dark brown color persists in ethanol. There are small hydroids growing near the base on the stalk. The stalk is wiry, 0.8 – 1 cm in diameter and gradually widens into the softer, more elastic tube at a height of 2.5 cm. The base of the stalk is torn, without any remains of the substrate, so it might have been a little longer (Fig. 14 A). The outer walls of the tube are smooth (Fig. 14 B) and 2.4 – 4 mm in thickness. Small circular openings, presumably ostia, flush with the surface, are scattered over the surface and are 0.5 – 1 mm in diameter. The consistency is soft, very elastic. The inner walls of the tube bear numerous larger circular openings, presumably oscules, 1 – 2.5 mm in diameter (Fig. 14 C). Skeletal structure: In the ectosome, nearly rectangular brushes of anisotornotes cause a microhispid surface (Fig. 14 D). In the choanosome pauci- to polyspicular tracts of thick styles are bound by spongin and connected by paucispicular tracts of the same styles (Fig. 14 E). Spicules: Ectosomal anisotornotes often have a prominent tooth at the thicker end and measure 228 – 335 x 8 – 10 µm (Figs. 15 A & B), choanosomal thicker styles measure 328 – 412 x 13 – 20 µm (Fig. 15 A). Microscleres are large polydentate isochelae, 72 – 91 µm (Figs. 15 C & D) and smaller polydentate isochelae, 28 – 45 µm (Figs. 15 E & F).	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891EFFFEFF28FD7FE5519F0D.taxon	discussion	Discussion. As with the species described above we compare Stelodoryx siphofuscus n. sp. with the eight species of Stelodoryx already recorded from the North Pacific and the North Atlantic Oceans (Table 5) and with S. mucosa, described above. S. siphofuscus differs from these species in the following characters: S. flabellata: North Atlantic and Arctic Oceans. A funnel-shaped sponge, 15 cm in height, with thinner ectosomal tornotes without apical tooth, with choanosomal acanthostyles, and one category of chelae only which is of intermediate size. S. lissostyla: North Pacific Ocean (Sea of Japan and East Sea). A sponge with thinner ectosomal tornotes, thinner choanosomal styles, two categories of considerably smaller isochelae. S. oxeata: North Pacific Ocean (Aleutian Islands). A stalked sponge with a ridged surface or massively encrusting with a smooth surface, greenish yellow in color, choanosomal oxeas with microspined ends, three categories of isochelae and one category of sigmas. Ectosomal tornotes are microspined and smaller. S. pectinata: North Atlantic Ocean (Azores, Canaries, Madeira). A sponge with smooth ectosomal tornotes which are longer and thinner, with choanosomal acanthostyles, two categories of isochelae of different sizes. S. pluridentata: North and South Atlantic Ocean. A stiff, yellowish orange to brown colored sponge with tornotes with microspined ends, larger choanosomal styles, one category of isochelae only. S. procera: North Atlantic Ocean (Azores, Canaries, Madeira). A sponge with smooth ectosomal tylotes which are thinner, two categories of smooth choanosomal styles, and one category of isochelas only. S. toporoki: North Pacific Ocean (Sea of Okhotsk and central Aleutian Islands) and Arctic Ocean. A stalked funnel-shaped sponge with much longer choanosomal styles, two categories of isochelae of very different size. S. vitiazi: North Pacific Ocean (Sea of Okhotsk, western Bering Sea and central Aleutian Islands). A tubeshaped or irregularly cylindrical sponge with thinner ectosomal tornotes, with larger choanosomal acanthostyles, only one category of isochelae which does not fit into one size category of S. siphofuscus. S. mucosa: is a massively encrusting light brown sponge, has microspined smaller tornotes, larger choanosomal spicules which are acanthostyles, only one category of isochelae which are of intermediate size and it has sigmas.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F029891EFFFEFF28FD7FE5519F0D.taxon	etymology	Etymology. From the Latin sipho — tube and the Latin fuscus — dark brown, meaning dark brown tube.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFCFF28FA43E3A998F1.taxon	materials_examined	Type species: Spongia fragilis Montagu, 1814 (type by subsequent designation)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFCFF28FF53E3B29DE1.taxon	materials_examined	Type species: Raspailia irregularis Hentschel, 1914 (by original designation)	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFCFF28FE8EE49599A8.taxon	materials_examined	Material examined. Holotype: ZSM 20150392, collected by Jim Stark with a research survey bottom trawl (haul # 193) from the FV Ocean Explorer; 27 July 2012, 228 m depth, 30.6 km SSE of Fox Beach Point, Shemya Island, Semichi Islands, western Aleutian Islands, North Pacific Ocean (52 ° 26.5920 ' N, 174 ° 18.1740 ' E). Water temperature = 3.7 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFCFF28FE8EE49599A8.taxon	description	Description. Habitus: Pale ochre-colored, bushy sponge with a height of 7 cm and a diameter of 4.5 – 5.5 cm (Fig. 16 A). It grows on a bivalve (Astarte sp.) shell with several points of attachment. Skeletal structure: There is no special ectosome developed. The choanosome is plumose, with the longitudinal axis of the sponge formed by polyspicular tracts of styles which diverge into spicule tracts running obliquely to the surface, ending there without getting much broader. Spicule tracts of styles are echinated by numerous acanthotylostyles, standing perpendicular, obliquely or even parallel to the tracts (Figs. 16 B & C). Spicules: Smooth styles, 956 – 1520 x 22 – 44 µm (Fig. 16 D), acanthotylostyles with a smooth, very pronounced tyle, characteristic for the subgenus, 150 – 234 x 18 – 33 µm (Fig. 16 E), with the tyle being the thickest part of the spicule.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFCFF28FE8EE49599A8.taxon	discussion	Discussion. Assignment to the subgenus Hymeraphiopsis is justified due to the presence of the echinating acanthostyles with smooth and very swollen tylote bases; a characteristic diagnostic for the subgenus (Hooper, 2002 d). This is only the second species for this subgenus, the only other species known, the type species, Raspailia (Hymeraphiopsis) irregularis Hentschel, 1914, is from the Antarctic Region. The characteristics of this species (after Hooper, 2002 d) are: styles, 1969 – 3016 x 35 – 54 µm, styles or anisoxeas, 435 – 712 x 2 – 11 µm, and acanthostyles, 181 – 301 x 12 – 24 µm). R. fruticosa differs from the type specimen in growth form: while the type is bushy without a dominating axis the new species has only short side-branches diverging from a main axis. It has smaller and generally thinner styles, smaller and thicker acanthostyles, and lacks the ectosomal oxeas.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFCFF28FE8EE49599A8.taxon	etymology	Etymology. From the Latin fruticosus — bushy, referring to the habitus of the sponge.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFBFF28F9E1E28498F0.taxon	materials_examined	Material examined. Holotype: ZSM 20150393, collected by Dave Somerton with a research survey bottom trawl (haul # 15) aboard the FV Alaska Provider; 1 June 2013, 93 m depth, 10.7 km south of Sedanka Island, east end of Unalaska Island, eastern Aleutian islands, Gulf of Alaska (53 ° 36.6380 ' N, 166 ° 12.4800 ' W). Water temperature = 4.5 ° C. Complete specimen in ethanol.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFBFF28F9E1E28498F0.taxon	description	Description. Habitus: The sponge consists of a group of agglutinated tubes starting from a single stalk with maximum height of 9.7 cm (Fig. 17 A). The stalk is 1 cm in diameter with a length of 1.8 cm before the sponge widens to a central area where seven tubes diverge. Single tubes are 0.8 to 1.4 cm in diameter with lengths between 2.7 and 4 cm. Thickness of the tube walls varies from 2 – 4 mm. The consistency of the tubes is soft and elastic while the stalk is hard and only slightly elastic. The color is light brown to beige and the surface is smooth and velvety, openings are recognisable at the top the tubes only (Figs. 17 B & C). Skeletal structure: The choanosome consists of a meshwork of spongin fibers loaded with foreign spicules and sediment, mesh-sizes variable, 130 – 880 µm. Sections perpendicular to the surface reveal smaller meshes, approximately 100 – 200 µm in diameter, in an area from the surface down to 300 – - 500 µm into the interior of the sponge, then larger meshes of mostly elongated rectangular shape dominate (Fig. 17 D). Ascending spongin fibers are 120 – 250 µm in diameter, connecting fibers are 40 – 150 µm (Figs. 17 E & F). Spongin fibers ascend obliquely to the surface. The ectosome is also a reticulation of spongin fibers cored by foreign particles and connecting the fibers reaching the surface. Ectosomal fibers measure 35 – 80 µm in diameter, forming a network with diameters of 50 – 350 µm.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFBFF28F9E1E28498F0.taxon	discussion	Discussion. Sponges of the orders Dictyoceratida and Dendroceratida are mainly known from warmer seas. Our record of a species of Dysidea is the first for the order Dictyoceratida from Alaska. There are two other records of the genus from the North Pacific: D. minna Hoshino, 1985 from the Sea of Japan and D. fragilis (Montagu, 1814) sensu Koltun, 1959 reported from the Arctic Ocean (Barents Sea including the White Sea, the Kara Sea, and Laptev Sea) and the Sea of Japan. The geographical records from Koltun (1959) are listed as inaccurate in the WPD although quite possibly a species of Dysidea but not D. fragilis. As Koltun (1959) described a Dysidea with a conulose surface, it is different from the species presented here. If the WPD is correct and Koltun´s record is not conspecific with D. fragilis then the species reported from Koltun probably is another undescribed species of Dysidea from this region. The species described here is indeed unusual for the genus as it has a smooth surface. Dysidea are thickly encrusting, massive, or branching sponges often with a marked conulose surface and a distinct net or web-like surface pattern, interconnecting between conules (Cook & Bergquist, 2002). The skeleton consists of a regular, usually rectangular arrangement of concentrically laminated primary and secondary fibres (all axially to fully cored); the former oriented perpendicular to the sponge surface (Hooper and Van Soest, 2002). The WPD lists 57 valid species of Dysidea with only five occurring in the North Pacific and North Atlantic Oceans. This is the first record of the order Dictyoceratida from Alaska. D. kenkriegeri differs from these species in the following characters:	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
EF19F0298913FFFBFF28F9E1E28498F0.taxon	etymology	Etymology. Named after Ken Krieger, retired fisheries research biologist for the Alaska Fisheries Science Center, NOAA, National Marine Fisheries Service (United States), and from the German word " Krieger " meaning " warrior. " Ken was a not only a pioneer of Gulf of Alaska deep-sea research, but true to his namesake, a warrior who fought for the continuation of that work.	en	Lehnert, Helmut, Stone, Robert P. (2015): New species of sponges (Porifera, Demospongiae) from the Aleutian Islands and Gulf of Alaska. Zootaxa 4033 (4): 451-483, DOI: 10.11646/zootaxa.4033.4.1
