Cliona flavifodina Rützler 1974

Cliona flavifodina

DIAGNOSIS.—Papillae yellow-brown, circular, discrete, 2.8 mm (mean diameter). Excavations irregular, tunnel shaped, confluent; filled by yellow, tough tissue. Tylostyles straight, with droplet-shaped or elongate heads, 318.1 × 7.4 μm (mean length × width). Spirasters with thin shaft, average 3–4 bends, 36.9 × 1.6 μm (mean length × width of shaft), and discrete slender spines, 4.5 μm (mean length).

DESCRIPTION.—Ectosome: The color of the papillae varies from bright yellow to grayish yellow and chestnut brown. In alcohol and upon drying, it fades to pale gray or grayish brown. The papillae are inconspicuous, level with the surface of the substratum, and well spaced (Figure 5a). Not more than ten could ever be observed in any one specimen. Their shape is circular, rarely elongate; their diameters are 1.5 × 1.5 mm-5 × 3 mm (2.8 × 2.2 mm). Papillary fusion is an exception. The surface of the papillae is irregularly porous. Oscula are rare; they open to about 3 mm diameter and have a slightly raised rim. The ectosome contains an abundance of granular cells, ovoid to irregularly elongate, 16 × 16 μm-38 × 8 μm, with granules of 1 μm. A small amount of zooxanthellae was observed in one specimen.

Choanosome: Grayish yellow tissue lines the papillary canals. These open into large, irregular spaces filled with a tough cavernous tissue (Figure 5b). The color of the choanosome is bright yellow to deep ocher, occasionally with an orange tinge. In alcohol or when dried, it becomes pale gray. In addition to the granular cells mentioned above, there are numerous cells of a second kind. They are more or less spherical, 18–22 μm in diameter, with a small anucleolate nucleus (like the gray cells), and packed with large spheroid basophilic granules of 1.5–2 μm (Figure 5f).

Excavation: The size of the circular papillary perforations (Figure 5c) corresponds to that of the papillae, although in the macerated specimens measured, it only ranged from 0.5 × 0.5 mm-3.2 × 2.2 mm (1.7 × 1.1 mm); one double perforation was 4.8 × 4.3 mm. The papillary canals are 1.1–7.0 mm (3.1 mm) long, until they widen and reach the choanosomal portion of the sponge. No chambers are developed, at least in the present material. There are large irregular spaces (Figure 5d) with tapering tunnels radiating into the substratum to a depth of 20 mm. Horizontal extension of the excavations reaches 25 mm.

Spicules: The papillae are armed with perpendicular typostyles (Figure 5e). The choanosome contains tylostyles and large numbers of spirasters. The tylostyles (Figures 6a–d) are mostly straight; occasionally they are bent shortly behind the head. The heads are droplet shaped or elongate ovoid; most of them show a central dark spot in transmitted light. Secondary swellings produce characteristic violin-shaped and almost rectangular heads, with an opaque spot close to the neck. The spirasters (Figures 6b–d, 7) are uniform in appearance, with a thin shaft and a moderate number of slender but prominent spines. Most of them have four bends, but some are straight with reduced spines (amphiasters).

Spicule dimensions (in μm): Tylostyles, length × width: 178.0–409.4 × 0.7–11.1 (318.1 × 7.4). Neck width: 2.2–10.4 (5.8). Head length × width: 5.9–24.1 × 3.7–17.8 (15.5 × 11.5). Spirasters, length × width (shaft only): 14.4–65.6 × 0.5–3.2 (36.9 × 1.6). Spine length × width (at base): 1.4–7.7 × 0.6–1.9 (4.5 × 1.5). Number of spines: 8–27 (17.4). Number of bends: 1–5 (3.3). Amphiasters, length × width (shaft only): 9.6–38.4 × 0.6–2.5 (22.9 × 2.3). Spine length × width (at base): 1.8–3.2 × 0.5–1.6 (2.7 × 1.1). Number of spines: 5–14 (9.3).

DISTRIBUTION.—Bermuda.