Esperiopsis cimensis Soest, Beglinger & Voogd, 2012, sp. nov.

• Main Authors: Van Soest, Rob W. M., Beglinger, Elly J., de Voogd, Nicole J.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2012
• Subjects: Biodiversity; Taxonomy; Animalia; Porifera; Demospongiae; Poecilosclerida; Esperiopsidae; Esperiopsis; Esperiopsis cimensis; Van Veen; North Atlantic Deep Water; North Atlantic
• Online Access: https://zenodo.org/record/3858668; https://doi.org/10.5281/zenodo.3858668

Esperiopsis cimensis sp. nov. Fig. 6 Etymology Named after the type locality, Ilheu de Cima. Material examined Holotype ZMA Por. 07282, Cape Verde Islands, SW of Ilheu Rombos, SE of Ilheu de Cima, depth 165 m, hard bottom with yellow calcareous sand, coll. R. W.M. Van Soest, CANCAP 7 Expedition stat. 030/05, 14.95°N 24.65°W, Van Veen grab, 23 Aug. 1986. Description Thinly encrusting on a large volcanic stone (Fig. 6A, arrow), alongside a specimen of Aplysilla Schulze, 1878. Size of crust 3.5 x 2 cm, thickness 1-2 mm. Colour: yellow alive, beige in alcohol. Surface optically smooth. Consistency soft. SKELETON. (Fig. 6B) Plumose, with strongly developed spicule bundles traversing the sponge at right angles to the surface, where they fan out. Few if any connecting spicules. No special ectosomal skeleton. There is a ‘groundmass’ of microscleres crowding the space between the spicule bundles and adhering to it, mostly consisting of sigmas and small isochelae. Scattered larger chelae, rather rare, mostly occurring at the surface. SPICULES. (Fig. 6 C-E) Styles, sigmas, palmate isochelae. STYLES. (Fig. 6C, C 1) Long and thin, straight or slightly curved, 396- 431.4 -461 x 5- 6.4- 8 µm. SIGMAS. (Fig. 6D) In two distinct non-overlapping size categories, both thin and strongly curved: (I) 76- 85.8 - 96 µm (Fig. 6D 1), and (II) 36- 45.4 - 56 µm (Fig. 6D 2). PALMATE ISOCHELAE. (Fig. 6E) In two distinct, non-overlapping size categories, the larger (I) ‘normal’ in shape (Fig. 6E 1), 56- 69.4 - 84 µm, the smaller (II) with incurved median alae (Fig. 6E 2), 14- 16.9 - 21 µm. Distribution and ecology Only known from the type locality S of Ilheu de Cima, Cape Verde Islands (Fig. 1, loc. 5), on volcanic bottom with yellow sand, at 165 m depth. Remarks The new species appears to be a member of a group of morphologically similar North Atlantic deep-water species (see Table 1), sharing the encrusting habit, the size and shape of megascleres and two categories of both sigmas and chelae. Probably closest is Esperiopsis flagellum ...