Eurypon Gray, 1867

Ott, B., Mcdaniel, N. & Humphrey, E., 2024, Fourteen new species of demosponges (Porifera) from three coastal fjords in southern British Columbia, Canada, Zootaxa 5463 (2), pp. 151-200 : 154-156

Genus Eurypon Gray, 1867

Worldwide 54 species have been described (de Voogd, et al. 2023). The Eurypon genus is cosmopolitan, reported from the Atlantic (north, south, east, west), Mediterranean (east and west), Caribbean, Pacific (north, south, east, west; no previous published records north of Mexico for the Northeast Pacific), Indian Ocean, Red Sea, Aegian Sea, Barents Sea (north and south). None have been reported for arctic or antarctic seas. Eurypon species occur discontinuously bathymetrically from littoral to over 2400 m. No Eurypon species spans shallow to deep water (with the possible exception of E. viride [ Topsent, 1889]: 67–842 m). Eurypon species have been recorded in the Northwest Pacific in Japan ( Eurypon duoacanthostyla ( Hoshino, 1981) , Eurypon inuisitatiacanthostyla ( Hoshino, 1981)) . Northeast Pacific Eurypon were recorded for the Pacific coast of Mexico ( Eurypon atriciae Aguilar-Camacho & Carballo, 2013 , Eurypon brunum Aguilar-Camacho & Carballo, 2013 , Eurypon diversicolor Aguilar-Camacho & Carballo, 2013 ) and Hawaii ( Eurypon nigrum Bergquist, 1967 ). Most Eurypon species are thin encrusting (0.25–2 mm), with a hispid or hirsute surface, and yellow to orange. Skeleton is commonly microcionid, usually with erect style variants (tylostyles, subtylostyles, styles), with acanthostyles heads down on a spongin basal plate; tornotes, oxeas or strongyles may replace or complement stylote spicule types. Microscleres, if present, are raphides which may form trichodragmas. A specialized ectosome is often lacking (Hooper 2002 [2004]a). A number of Eurypon species, including some in the North Pacific have the main skeleton echinated by acanthostyles or other spicules, i.e., are considered to be hymedesmioid (see Table 2 ).

We identify three new species of Eurypon from BC fjords which fit Hooper’s definition of the genus. Based on published descriptions, none of the BC specimens is conspecific with North Pacific described species (see Table 2 and Remarks under each species).

Tables

TABLE 2. North Pacific Eurypon species comparison.

Species	Distribution	Key Characteristics
E. brunum Aguilar-	Mexico, Pacific coast,	Encrusting sponge, size 3–4 cm length × 1–3 cm width and 5–7 mm thick growing over rocks. Oscula and ostia not visible.
Camacho & Carballo, 2013	4–11 m depth	Surface hispid. Colour in life black or dark brown. Skeleton hymedesmioid. No specialized ectosome. Choanosomal
		skeleton with main subtylostyles and acanthostyles embedded in a spongin layer. The styles/anisoxeas are dispersed in the
		subectosomal region. Straight choanosomal subtylostyles 700–1625 and 110–375 µm. Acanthostyles with short recurved
		spines 200–390 and 60–190 µm. Straight or curved subsurface styles/anisoxeas 260–520 µm.
E. diversicolor Aguilar-	Mexico, Pacific coast,	Encrusting sponge, size 3–6 cm length × 2–5 cm width and 2–10 mm thick. Oscula and ostia not observed. Surface hispid
Camacho & Carballo, 2013	10–20 m depth	with spicule projections evenly distributed. Colour green. Skeleton hymedesmioid. No specialized ectosome. Choanosomal
		with main subtylostyles and acanthostyles erect in a spongin layer; subtylostyles penetrate the surface. Straight choanosomal
		subtylostyles 900–1710 µm. Curved or straight acanthostyles with prominent recurved spines 210–390 and 60–180 µm.
E. duoacanthostyla	Japan, 15 m depth	Small thin (2 cm) sponge growing on polychaete tubes. Surface smooth, uneven or wrinkled. Ostia and oscula not visible .
( Hoshino, 1981)		Colour in life peach red-orange. Ectosome confused, tangential styles 50–80 µm thick. Choanosome irregular arrangement of
		styles, rarely acanthostyles. Occasional tracts of styles tangential to surface. Styles smooth, straight, apices hastate or acerate,
		250–320 µm. Long acanthostyles nearly straight or slightly bent, base swollen 250–280 µm. Short acanthostyles straight or
		nearly straight, base swollen and irregularly spined; sparsely spined shaft 138–180 µm.
E. inuisitatiacanthostyla	Japan, 15 m depth	Irregular massive, aggregated numerous slender and erect solid tubes; tubes tightly contiguous in upper mass. Surface smooth ,
( Hoshino, 1981)		uneven. Oscula and ostia not visible. Colour in life jasper red or orange-red. Ectosome confused, horizontal arrangement of
		strongyles about 200 µm thick. Choanosome vague tracts of 10–20 rows of strongyles parallel to surface connected in places
		with coarse irregular reticulation of strongyles. Acanthostyles uncommon, scattered on or near tracts. Strongyles nearly
		straight mostly cylindrical or slightly tapering toward ends; occasionally substylote, 325–430 µm. Acanthostyles rare to
		uncommon, middle smooth, spined or roughened at each end. Base slightly swollen and apex tapering or abruptly pointed.
		Shaft nearly straight or irregularly bent near base, 325–470 µm.
E. nigrum Bergquist, 1967	Hawaii, 5–11 m depth	Very thin encrusting; surface hirsute; blue in life. Spicules extend 1 mm. Skeleton composed of a sparse basal palisade of
		acanthostyles, interspered with tufts of 2–8 tylostyles which penetrate the surface. Shorter tylostyles dispersed w/o order.
		Large tylostyles: curved basally and often asymetrical. head, 1200–2400 µm. Short tylostyles: same morphology as large,
		170–800 µm. Acanthostyles: entirely spined. 70–165µm.
E. patriciae Aguilar-	Mexico, Pacific coast,	Encrusting, 2–4 cm × 1–3 cm, 6–8 mm thick growing over rocks. Oscula and ostia not visible. Surface hispid due to
Camacho & Carballo, 2013	5 m depth	evenly distributed projecting spicules. Colour in life yellow or green. Skeleton hymedesmioid. No specialized ectosome.
		Choanosome tylostyles and acanthostyles embedded in a spongin layer. Strongyloxeas and styles are dispersed in groups
		of one to three arranged along the tylostyles in the choanosome and penetrate the surface. Straight choanosomal tylostyles
		1320–2400 µm. Acanthostyles with short recurved spines 130–180 and 55–87.5 µm. Straight strongyloxeas/styles: 400–550 x
		5–10 µm.
E. tylospinosum Aguilar-	Mexico, Pacific coast,	Encrusting 2–5 cm × 1–2 cm, 3–5 mm thick. Oscula and ostia not visible. Surface smooth. Colour in life red. No specialized
Camacho & Carballo, 2013	15 m depth	ectosome. Choanosome main subtylostyles and acanthostyles embedded in a spongin layer). The styles/anisoxeas are
		dispersed in trichodragmas in the subsurface region. Choanosomal subtylostyles with a pronounced head or modified to
		style 200–575 µm. Acanthostyles with swollen head with prominent spine arranged as a crown around the head 70–200 µm.
		Straight or curved subectosomal styles/anisoxeas 330–460 × 1.75–2.5 µm.