Cladorhiza kensmithi, Austin, 2017

Lonny Lundsten, Henry M. Reiswig & William C. Austin, 2017, Three new species of Cladorhiza (Demospongiae, Poecilosclerida, Cladorhizidae) from the Northeast Pacific Ocean, Zootaxa 4317 (2), pp. 247-260 : 250-253

Cladorhiza kensmithi sp. nov.

Figs. 2–3 , Table 1, Supplemental Table 1

Type material. Holotype: CASIZ Cat. No. 138573, Acc. No. 60917, MBARI-T199- A1, Gorda Ridge (40° 45' 44.244" N, 127° 32' 48.2604" W, 3242 m), Northern California, USA, ROV Tiburon from R/V Western Flyer, originally fixed in 5% SWF. Date of collection August 18, 2000 ; Paratype: CASIZ Cat. No. 219701, D231-As, Station M (35° 10′ N, 122° 59′ W, 4000 m) ROV Doc Ricketts from R/ V Western Flyer , Central California, USA, Date of collection May 25, 2011, 95% ethanol; Other non-type specimens ( Supplemental Table 1): Vicinity of Station M, Central California, USA (35° 10′ N, 122° 59′ W), including CASIZ 219702 95% ethanol, ( MBARI D231a,b, ROV Doc Ricketts from R/ V Western Flyer, May 25, 2011), CASIZ Cat . No. 219703 ( MBARI T1143, ROV Tiburon from R/V Western Flyer, September 23, 2007) 95% ethanol, CASIZ Cat . Nos. 119073 (Pulse 2, Sta. 216 M, 4100 m) fixed in 5% SWF, 119072 ( Pulse 25, Dive 2922, 4087 m) R/ V New Horizon, 40’ otter trawl, dry, west of Patton Escarpment , Southern California, USA; SCRIPPS Institute of Oceanography Benthic Invertebrate Collection Cat. Nos. P954 (MET Sta. 129, 3640 m), P970 (MET Sta. 133, 3689 m) R/ V New Horizon, 40’ otter trawl, originally fixed in 5% SWF .

Type locality. Holotype: Gorda Ridge , Northern California, USA, 40° 45' 44.244" N, 127° 32' 48.2604" W, 3242 m ; Paratype: Station M, Central California, USA, 35° 10’ N, 122° 59’ W, 4000 m ; Additional non-type specimens: Vicinity of Station M, Central California, USA, 35° 10’ N, 122° 59’ W.

Etymology. Named in honor of Dr. Kenneth L. Smith Jr. for contributions to marine biology and ecology over the course of a more than 40-year career in which he has devoted much of his expertise to studying extreme habitats, including the deep sea and polar regions, and the impacts of a changing climate on these ecosystems.

Diagnosis. Crinorhiza form, parasol-shaped sponge, on long stalk with densely branching rhizoid. Two to four apical spermatocyst-bearing discs on short, slender stalks. Four size classes of megasclere styles including rare strongyles and two microsclere categories including tridentate unguiferate anisochelae and contort sigmancistra.

Description. Holotype: CASIZ Cat. No. 138573 Large, parasol-shaped sponge 32.5 cm total length with four 10.5 mm long apical extensions ending in 3.8 mm diameter discs, which are densely packed with spermatocysts. Parasol is 2.7 cm in diameter with fifty-four 2.4–3.7 cm long filaments radiating in all directions. Stalk, which is broken, is 1–2.1 mm in width and ends in a terminal rhizoid 5.5 cm long and 2.6 cm wide. On the stalk, 7.5 cm below the parasol an oocyte-embryo swelling is present that is 1.9 cm long and 2.9 mm wide and contains numerous mature oocytes and embryos. Paratype: Large, parasol-shaped sponge 20.8 cm total length with two 9– 11 mm long apical extensions ending in 4 mm diameter discs, which rise from a top-knot that is 7 mm above the apical surface of the parasol. Parasol is 1.9 cm in diameter with 1.6–5.5 cm long filaments radiating in all directions. Stalk is 1 mm in width and ends in a very bushy terminal rhizoid 4.65 cm long and 7 cm wide. On the stalk, 2.6 cm below the parasol an oocyte swelling is present which is 1.4 cm long and 2 mm wide and contains numerous mature oocytes and embryos. Preserved color yellowish-white, bright white in life.

Spicules ( Table 1): Large style 1 length 3993.7 ± 856.4 µm, n=161, width 62.4 ± 12.7 µm, n=114; large style 2 length 1254.8 ± 245.7 µm, n=378, width 22.4 ± 6.9 µm, n=248; large style 3 length 345.6 ± 105.2 µm, n=249, width 14.9 ± 2.1 µm, n=239; strongyle length 722.2 ± 301.2 µm (n=79), width 16.4 ± 6.2 µm (n=57); tridentate unguiferate anisochelae 35.2 ± 1.5 µm n=366; sigmancistra 46.5 ± 3.0 µm, n=143. Styles 1 occur mainly in the stalk but absent from antennae. Styles 2 occur everywhere but filaments. Styles 3 occur everywhere. Strongyles are present mainly in the root and less commonly in antenna stalks. Anisochelae cover all surfaces except the root and sigmancistras occur only in the antennae and antenna stalks. Paratype spicules: Large style 1 length 4 867.2 ± 891 µm, n=49, width 67.8 ± 17.8 µm, n=49; large style 2 length 2567.4 ± 565.2 µm, n=42, width 50.3 ± 19.6 µm, n=39; large style 3 length 902 ± 319.3 µm, n=48, width 22.5 ± 12.7 µm, n=46; strongyle length 539.3 ± 135.9 µm, n=55, width 17.1 ± 3.8 µm, n=55; tridentate unguiferate anisochelae 37.8 ± 1.5 µm n=27; sigmancistra 52.2 ± 6.6 µm, n=30. Additional non-type specimen spicule measurements are listed in Supplemental Table 1.

Habitat and associated fauna. Station M is an abyssal long-term research study area located at 4100 m off central California (Smith and Druffel 1998). It is characterized as a low-relief, silty-clay sedimented habitat with no evidence of sedimentary input from turbidity currents or slumping from the continental shelf. It has been shown to have strong, seasonally variable surface productivity. Long-term studies at this station have demonstrated rapid seafloor community composition changes in response to surface productivity ( Kuhnz et al. 2014). Video transects revealed that Cladorhiza kensmithi sp. nov. had variable densities of 0.022–0.097/m -2 between 2006 and 2012. Distribution tended to be patchy, with apparent juvenile specimens clumped and attached to plate sponges ( Bathydorus laniger and Docosaccus maculatus ). This change in density over the sampling interval was attributed to increased surface productivity, which also accompanied a shift in community structure from a suspension-feeder to a deposit-feeder dominated community. Kuhnz et al. (2014) should be consulted for a detailed review of community constituents, structure, and changes over time at Station M.

Remarks. Of the parasol morphology Cladorhiza species, C. kensmithi sp. nov. differs from previously described species in morphology and spiculation, but most closely resembles C. corona , C. similis , and C. longipinna . Cladorhiza kensmithi sp. nov. differs from all of these species in its external morphology, specifically in its adult reproductive form, in having long apical extensions terminating in flattened discs. Although desilicification and thin sectioning was performed on one disc, we were unable to determine if the spermatocysts were organized into spermatophores before release.

Figures

FIGURE 2. Cladorhiza kensmithi sp. nov. A, B) holotype in situ, C) preserved paratype, D) spermatocysts in apical disc of holotype, E) wide and close images of holotype oocyte swelling.

FIGURE 3. Cladorhiza kensmithi sp. nov. holotype SEM images of spicules A) tridentate unguiferate anisochelae, B) sigmancistra, C) strongyles and large styles of three size classes.