Vitrumanthus schrieri, Kise & Montenegro & Santos & Hoeksema & Ekins & Ise & Higashiji & Fernandez-Silva & Reimer, 2022

Kise, Hiroki, Montenegro, Javier, Santos, Maria E. A., Hoeksema, Bert W., Ekins, Merrick, Ise, Yuji, Higashiji, Takuo, Fernandez-Silva, Iria & Reimer, James D., 2022, Evolution and phylogeny of glass-sponge-associated zoantharians, with a description of two new genera and three new species, Zoological Journal of the Linnean Society 194, pp. 323-347 : 337-339

VITRUMANTHUS SCHRIERI SP. NOV.

( FIG. 6A–F )

Synonymy: Parazoanthidae sp. – Montenegro et al., 2020: 7–8, fig. 2; ‘zoanthid symbionts’, ‘zoanthids’ – Reiswig & Dohrmann, 2014: 241–242, fig. 4A, B; ‘white zoanthids’ – Van Soest et al., 2014: 438.

Z o o b a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org:act: D326729E-6617-4C5F-8F43-31C5C7133EF4.

Material examined: Holotype: RMNH.COEL.42429, SubStation , Curaçao, 12°14 ′ 01 ″ N, 68°53 ′ 32 ″ W, depth range 161–243 m, manned submarine Curasub, coll. B. W. Hoeksema, 31 Mar 2014, fixed in 99.5% ethanol.

Paratype: RMNH.COEL.42430, SubStation , Curaçao, 12°05 ′ 04 ″ N, 68°53 ′ 54 ″ W, c. 200 m deep, manned submarine Curasub, coll. B. W. Hoeksema, 21 Apr 2014, fixed in 99.5% ethanol .

Other material examined: RMNH.COEL.42620, Cargill Pier, Bonaire, Caribbean Netherlands, 12°04 ′ 47.9 ″ N, 68°17 ′ 37.7 ″ W, depth 223 m, manned submarine Curasub based on RV Chapman, coll. L. Becking and E. Meesters, 1 Jun 2013, fixed in 99.5% ethanol . RMNH.COEL.42621, Cargill Pier, Bonaire, Caribbean Netherlands, 12°04 ′ 47.9 ″ N, 68°17 ′ 37.7 ″ W, depth 248 m, manned submarine Curasub based on RV Chapman, coll. L. Becking and E. Meesters, 1 Jun 2013, fixed in 99.5% ethanol . RMNH.COEL.42622, Kralendijk Pier, Bonaire, Caribbean Netherlands, 12°08 ′ 48.9 ″ N, 68°16 ′ 55.6 ″ W, depth 140 m, manned submarine Curasub based on RV Chapman, coll. L. Becking and E. Meesters, 30 May 2013, fixed in 99.5% ethanol .

Etymology: The species is named for Adriaan ‘Dutch’ Schrier, owner of the manned submersible Curasub and RV Chapman, operated from Substation Curaçao, for his generosity in allowing BWH to sample specimens. The Japanese name is 'Amime-ruri-sunaginchaku'.

Description: External morphology. Circa 50 cylindrical polyps in preserved specimen. Solitary or colonial polyps rise irregularly from the hexactinellid sponge Verrucocoeloidea liberatoriii Reswig & Dohrmann, 2014 . Living polyps white and tentacle transparent in coloration. Preserved polyps dark beige. Surface of column rough and ectoderm continuous. Ectoderm and mesoglea of polyps encrusted with numerous and various sizes of sand and silica particles. The living expanded oral disks c. up to 8.0 mm in diameter, expanded polyps c. up to 10 mm in height, 1.0–5.0 mm in diameter. Preserved contracted preserved polyps 0.3–2.1 mm in height, 0.8–2.8 mm in diameter. Capitulary ridges indiscernible. Tentacles 20–24 in number.

Internal morphology. Zooxanthellae absent. Cyclically transitional marginal musculature. Encircling sinus present and basal canals of mesenteries absent. Mesenteries thin. Mesoglea thickness c. 0.6 mm. Mesoglea thicker than ectoderm and endoderm. Siphonoglyph distinct and V-shaped. Mesenterial filaments present.

Cnidae. Basitrichs and microbasic b-mastigophores, microbasic p-mastigophores, holotrichs and spirocysts ( Fig. 5B ; Table 2 ).

Distribution and habitats: Caribbean Netherlands: known from Curaçao and Bonaire at depths of 140– 248 m.

Associated hosts: Verrucocoeloidea liberatorii Reswig & Dohrmann, 2014 , Parahigginsia strongylifera Van Soest, Meesters & Becking, 2014 and Cyrtaulon sigsbeei ( Schmidt, 1880) .

Remarks: In terms of host hexactinellid sponges, Vitrumanthus schrieri can be distinguished from V. vanderlandi and V. oligomyarius ( Wassilieff, 1908) because only V. schrieri is associated with Verrucocoeloidea sponges. Vitrumanthus schrieri is not only associated with hexactinellid sponges, but also with Demospongiae species in the genus Parahigginsia ( Van Soest et al., 2014) . On the other hand, V. vanderlandi and V. oligomyarius are associated with Tretochone duplicata ( Topsent, 1928) . In addition, the column of V. schrieri is rough, due to heavy encrustation, while columns of V. vanderlandi and V. oligomyarius are smooth with almost no encrustations. Vitrumanthus sp. (NSMT-Co 1755) and V. vanderlandi are associated with Cyrtaulon species.

Reiswig & Dohrmann (2014) reported zoantharians were found on Verrucocoeloidea liberatorii , and we judge that these are likely V. schrieri based on external morphology and the host hexactinellid sponge species.

Figures

Figure 5. Cnidae in the tentacles, column, actinopharynx and mesenterial filaments of holotypes of new species in this study. A, cnidae of Churabana kuroshioae; B, cnidae of Vitrumanthus schrieri; C, cnidae of Vitrumanthus vanderlandi; D, cnidae of Vitrumanthus oligomyarius. Abbreviations: Hl, holotrichs large; Hm, holotrichs medium; Hs, holotrich small; O, basitrichs and microbasic b-mastigophores; Pm, microbasic p-mastigophores; S, spirocysts.

Figure 6. Images of external and internal morphology of Vitrumanthus schrieri (A, photographic record: image was taken at the entrance of Piscadera Bay, 12°07’06”N, 68°58’34”W; B–F, holotype: RMNH.COEL.42429). A, living polyps on Verrucocoeloidea liberatorii in situ; B, preserved polyps; C, close-up image of preserved polyp; D, close-up image of tentacle musculature; E, close-up image of cyclically transitional marginal musculature; F, drawing of cyclically transitional marginal musculature. Abbreviations: A, actinopharynx; Tem, tentacle musculature; Ctmm, cyclically transitional marginal musculature. Scale bars: 10 mm (A), 25 mm (B), 5 mm (C), 0.5 mm (D, E).