Rhabdocalyptus mirabilis Schulze. We 1899

• Main Authors: Reiswig, Henry M., Stone, Robert P.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2013
• Subjects: Biodiversity; Taxonomy; Animalia; Porifera; Hexactinellida; Lyssacinosida; Rossellidae; Rhabdocalyptus; Rhabdocalyptus mirabilis; Amchitka; Amchitka Pass; Alaska; Aleutian Islands
• Online Access: https://zenodo.org/record/5261630; https://doi.org/10.5281/zenodo.5261630

Rhabdocalyptus mirabilis Schulze, 1899 (Figs. 27 & 28, Table 14) Synonymy. Rhabdocalyptus mirabilis Schulze, 1899: 61. Acanthascus (Rhabdocalyptus) mirabilis Stone et al., 2011: 28. Material examined. USNM# 1196563, ROV ' Jason II' from RV ' Roger Revelle', dive J2105, 06 August 2004, Amchitka Pass, 11.4 km WNW of Cape Sajaka, Tanaga Island, Aleutian Islands, Alaska, 51º54.253'N, 178º23.235'W, 2311 m, dry & ethanol, base not collected. Comparative material. Rhabdocalyptus mirabilis, holotype, USNM 07574, USFS 'Albatross', stn 3338, 28 Aug. 1890, S of Shumagen Bank, Alaska, 54º19'N, 159º40'W, 1143 m, ethanol; Rhabdocalyptus sp., USNM 07573, USFS 'Albatross', stn 3008, 18 Mar. 1891, Gulf of California, 26º00'N, 111º06'W, 560 m, ethanol & dry. Description. The specimen in situ (Fig. 27A) was a curved, white, tubular sponge, 15.5 cm long by 10.1 cm diameter, with well-developed spicule veil and large terminal osculum. The major part of the specimen, but not the basal attachment, was collected, and after drying (Fig. 27B) is 14.0 cm long by 6.8 cm in flattened width and wall thickness to 6.0 mm. Prostal diactins project 10–15 mm only from the oscular margin (Fig. 27C) and a narrow 12 mm wide band of lateral surface below it; they are not found on most of the lateral surface. Raised hypodermal pentactins forming the veil, all paratropal and thorned, project nearly continuously to 3.4 mm in the diactin zone around the oscular margin and as small groups of 3–8 pentactins to 7.3 mm from the tips of low conules over most of the lateral body surface (Fig. 27D). Conules are 4.2–6.5–9.2 (n = 36) mm apart and 0.8–1.2–1.5 (n = 16) mm high. Short extremely paratropal pentactins with all four tangential rays emanating as a tight bundle within 15° (Fig. 27E) occur in the dense veil near the oscular margin but not over the general lateral body veil. The dermal surface is turned in ca 2 mm at the osculum margin forming a narrow diaphragm. The lateral dermal surface (Fig. 27F) is covered by conspicuous inhalant canals, ...