Eurypon reiswigi, Ott & Mcdaniel & Humphrey, 2024

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 : 156

Eurypon reiswigi n. sp.

urn:lsid:zoobank.org:act:277B3AEB-6A54-42AA-B879-F11E3D9551AC

Figure 2

Diagnosis. Relatively large aquiferous subdermal canal system renders a porous sponge skeleton with densely spaced ostia over the entire upper surface.

Etymology Named in honour of the late Dr. Henry Reiswig. Henry was always generous in sharing his considerable knowledge and skills with any who sought them. Henry contributed significantly to our knowledge of sponges, in particular those living in Pacific Ocean waters.

Material Examined Holotype RBCM 018-00123 - 002 , Stn NM 300 , Nine Mile Pt, Sechelt Inlet, BC, 49° 36.293’ N / 123° 47.139’ W, coll. N. McDaniel, 28 Jan 2015, 14 m depth, one specimen . Paratypes RBCM 018- 00182 - 001 , Stn NM 278 , Kunechin Pt, Sechelt Inlet, BC, 49° 37.060’ N / 123° 48.229’ W, coll. N. McDaniel, 8 March 2012, 15 m depth, one specimen ; RBCM 024-00007 - 001 , Stn NM 356 , Defence Isl, Howe Sd, BC, 49° 34.544’ N / 123° 16.632’ W, coll. N. McDaniel, 3 Apr 2017, 20 m depth, one specimen ; RBCM 024-00008 - 001 , Stn NM 404 , Defence Isl, Howe Sd, BC, 49° 34.511’ N / 123° 16.425’ W, coll. N. McDaniel, 14 Dec 2019, 15 m depth, 1 specimen ; RBCM 018-00226 - 002 , Stn NM 360 , Defence Isl (east), Howe Sd, BC, 49° 34.710’ N / 123° 16.242’ W, coll. N. McDaniel, 20 April 2017, 15 m depth, one specimen . Other Material Stn NM 332 , Sakinaw Rock, Sechelt Inlet, BC, 49° 34.009’ N / 123° 48.150’ W, coll. N. McDaniel, 18 March 2018, 20 m depth. 1 non-voucher specimen .

Description

External ( Figure 2A ) Holotype RBCM 018-00123-002. Encrusting bedrock or barnacles ( Balanus spp. ) up to 12 x 7 cm; base 2 mm thick. Surface with multiple erect processes to 5 mm high; may be reduced to papillae less than 5 mm high. Sponge open, porous; ostia numerous over the entire surface among the erect processes or papillae. Oscula not visually separable from ostia. Colour in life yellow or yellow-orange. Consistency compressible, soft, easily torn.

Skeleton No specialized ectosome. Hymedesmioid choanosome is composed of tracts of tylostyles and styles running perpendicular to the surface separated by large aqueous canals ( Figure 2B ). Near the surface where tufts occur styles form loose brushes to the surface, apices outward and projecting up to 1 mm. Styles and tylostyles compose the spicule tracts which are echinated by acanthostyles. Styles are tangentially oriented at the base with unoriented acanthostyles scattered throughout the basal area.

Spicules ( Figures 2C, D, E, F ) Styles, tylostyles, acanthotylostyles. Styles straight, curved or bent near the head; with long apices, dimension range 750– 2187 x 10.0–47.5 µm ( Figure 2C ). Tylostyles with spherical heads which may be offset from centre; apices moderately short; spicules uncommon, dimension range 600–1075 x 35– 50 µm ( Figure 2D ). Acanthotylostyles straight or slightly curved, entirely spined except mostly smooth spherical heads, dimension range 65–273 x 15.6–31.2 µm ( Figure 2E ). Small tylostyles with similar form to acanthostyles but without spines were relatively common in some of the specimens examined ( Figure 2F ); average size 99 x 18 µm or somewhat smaller than acanthostyles. These may be growth stages of acanthostyles although no incipient spination was noted in scanning electron micrographs (SEMs). Tahle 3 lists dimensions of specimens examined.

Distribution Eurypon reiswigi n. sp. is found in Howe Sound and Sechelt Inlet, BC; 14–20 m depth.

Ecology Forms small, encrustations on bedrock substrates to 12 cm diameter; may overgrow barnacles ( Balanus spp. ).

Remarks Eurypon reiswigi n. sp. skeletal organization differs from the other two new species and tylostyles of all are different lengths; all spicules of E. microtuberculum n. sp. are shorter. Referring to Table 2 , none of the previously described North Pacific species has a basal layer of spicules parallel to the surface. Eurypon brunum , E. diversicolor , E. inuisitatiacanthostyla and. E. tylospinosum have longer acanthostyles. Eurypon duoacanthostyla is not hispid from projecting spicules, has a tangential ectosome layer of spicules and two sizes of acanthostyles. Habitus of E. inuisitatiacanthostyla is tubular and not thin encrusting and choanosome tracts are strongyles. Eurypon nigrum has two size classes of tylostyles.

Figures

FIGURE 2. Eurypon reiswigi n. sp. Holotype RBCM 018-00123-002. (A) In-situ. (B) Skeleton cross section. (C) Styles. (D) Tylostyles. (E) Acanthotylostyle. (F) Small tylostyle, may be acanthostyle growth stage.