Celleporaria firmispinosa
Creators: name: Martino, Emanuela Di
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Bryozoa
Gymnolaemata
Cheilostomatida
Celleporidae
Celleporaria
Celleporaria firmispinosa

description: Celleporaria firmispinosa (Silén, 1954)
(Fig. 35; Table 32)
Holoporella firmispinosa Silén, 1954: 38, figs 18, 19.
Material examined. Holotype by original designation LUZM 56.2 (Fig. 35A–E), south-western region of Western Australia, 7 miles NE of Cape Naturaliste. Leg. Prof. T. Gislén, Australia Expedition 1951–1952, collected 4.1.1952. Additional material: LUZM 56.1 (Fig. 35F–I), Warnbro beach, Perth, Western Australia; depth 18 m. Leg. Prof. T. Gislén, Australia Expedition 1951–1952, collected 30.11.1951. Both specimens encrusting algae.
Description. Colony encrusting, mounded multilayered (Fig. 35A, F, G).
Autozooids distinct, with deep interzooidal furrows, erect and chaotically arranged in the central area of the colony, rectangular along the growing edge, longer than wide (mean L/ W 1.38); frontal shield convex, coarsely granular (granules about 20 µm in diameter), imperforate except for a few, circular marginal areolar pores scattered along the zooidal outline, 10–25 µm in diameter (Fig. 35A).
Orifice transversely D-shaped with straight proximal margin lacking any structures, surrounded by a band of smooth calcification, more extensive proximally (about 30 µm wide), sloping steeply laterally placing the opening at a lower level than the frontal (Fig. 35B, D); two robust distolateral spines 30–60 µm in diameter, 120–250 µm long (Fig. 35A, B).
Adventitious avicularium suboral, placed parallel to the proximal margin of the orifice, medially or on one side, oval with raised rostrum directed laterally and outwards at about 45° in respect to the frontal plane (Fig. 35B–D); mandible semielliptical (Fig. 35B, C); some zooids developing a robust, ridged, conical suboral mucro bearing the avicularium, 110–150 µm long (Fig. 35G, I). Interzooidal avicularia absent.
Ovicells hood-shaped, not closed by the operculum (Fig. 35E, H); ooecium granular as the frontal shield, imperforate, sometimes with a blunt umbo centrally; no spines visible in ovicellate zooids.
Remarks. As seen in Amphiblestrum crassispinosum, another species growing on algae, this species also shows long oral spines, a stout suboral mucro and sometimes an umbo on the ooecium, which can be interpreted as an adaptation to the flexible substrate (i.e. algae) they encrust (see also Di Martino & Rosso 2021).
More than 30 species of Celleporaria are known from Australian waters (Cook et al. 2018). Celleporaria bispinata (Busk, 1854), recorded from south-western Australia and Tasmania, is the most similar to C. firmispinosa. Both species lack interzooidal avicularia and have a simple orifice devoid of any structures on the proximal margin, two robust and long distolateral spines, and a suboral avicularium that in some zooids is lodged on a well developed mucro (see Cook et al. 2018, fig. 3.130A for C. bispinata). Also, Celleporaria bispinata has two large, rounded oral condyles and avicularium with denticulate rostrum, features not observed in C. firmispinosa.
description: Published as part of Martino, Emanuela Di, 2023, Scanning electron microscopy study of Lars Silén's cheilostome bryozoan type specimens in the historical collections of natural history museums in Sweden, pp. 1-106 in Zootaxa 5379 (1) on pages 65-67, DOI: 10.11646/zootaxa.5379.1.1, http://zenodo.org/record/10209083