Beania australis Busk, 1852

Vieira, Leandro M., Migotto, Alvaro E. & Winston, Judith E., 2010, Shallow-water species of Beania Johnston, 1840 (Bryozoa, Cheilostomata) from the tropical and subtropical Western Atlantic, Zootaxa 2550, pp. 1-20 : 3-6

Beania australis Busk, 1852 b

( Fig 2–4 , 18 ; Table 1 )

Beania australis Busk, 1852b: 32 , pl. 16, fig 1–3; Marcus 1937: 63, pl. 13, fig. 32; Marcus 1949: 2; Vieira et al. 2008: 17 (checklist).

Material examined. MZUSP 0 23, Santos, São Paulo state, Brazil, E. Marcus det. (1938) on rock; MZUSP 377–378.

Description. Colony uniserial, branched, white in color. Zooids oblong, suberect, with an erect boatshaped portion and a long and slender connective tube. Erect portion obliquely inclined, convex basally, with a flat wholly membranous frontal surface. Connective tube proximal, about 0.271–0.802 mm in length and 0.037–0.043 mm in width, joined to the basal part of zooid; each zooid with 1–3 basal tubes. Two pairs of short distal (oral) spines around operculum and 10–19 opesial spines on each side, overarching frontal membrane, sometimes overlapping. Opesial spines reaching or sometimes exceeding the midline of membrane. Tubular radicles with branched ends present proximal to boat-shaped portion of some zooids. Avicularia absent. Ovicells absent.

Remarks. Beania australis was described from Cape Horn by Busk (1852b), as characterized by autozooids with 18–20 spines on each side of the frontal membrane, reaching to midpoint of the opesia. Marcus (1937) recorded this species in Santos (São Paulo state, Brazil) and described zooids with 17–22 pairs of lateral spines. However, specimens identified by Ernst Marcus and deposited in the Museu de Zoologia (MZUSP 023) have only 10–15 pairs. In the Brazilian specimens, the number of opesial spines may increase with the size of the zooid.

Hayward and Ryland (1995) described a new species, Beania pectinata , collected on Sargassum sp. from Heron Island ( Australia). It resembles B. australis in several aspects – dimensions of autozooids, presence of four short distal spines, four basal connective tubes, peri-opesial spines forming a comb-like frontal shield, and lack of avicularia – but the 25 pairs of closely aligned lateral spines in B. pectinata are highly distinctive.

The frontal membrane of specimens of B. australis from Alagoas state ( Brazil) is about 0.5 mm long, whereas, according to a drawing by Marcus (1937) of specimens from Santos ( Brazil), the length of the frontal membrane is about 0.85 mm. We examined specimens from Santos in the Museu de Zoologia da Universidade de São Paulo (MZUSP 023) identified by Ernst Marcus and found that their length to be ca 0.60 mm, slightly longer than specimens from Alagoas.

The beaniid genus Stolonella , established monotypically for S. clausa Hincks, 1883 from the Australian region, resembles B. australis in autozooid appearance (with a comb-like frontal shield and lack of avicularia), but the zooids are borne directly on kenozooids (true stolons). The basal tubular processes in autozooids of Beania australis are similar to those in B. mirabilis , being formed by the slender proximal tube of the zooid rather than a kenozooid, indicating a closer relationship with Beania .

Biological notes. The colonies of B. australis studied were collected on rocky shores in shallow water, where it is epiphytic on red algae and epilithic on rocks ( Table 6). Some colonies were also found in shrimp bycatch in the south of Alagoas state, at ca 15 m deep on the bryozoan Celleporaria sp.

Distribution. Atlantic: Cape Horn and Patagonia ( Busk 1852b); Brazil: São Paulo ( Marcus 1937; present study), Espírito Santo ( Marcus 1949) and Alagoas (present study).

Beania cupulariensis Osburn, 1914: 190 , figs 6–7; 1940: 399; Marcus 1944: 1, figs 1–4; 1955: 291, pl. 4, figs 41–43; Fransen 1986: 80, figs 26a–d; Winston 1986: 5; Vieira et al. 2008: 17 (checklist).

Material examined. MZUSP 0 0 7, 1948, Ilhabela, São Paulo state, Brazil, E. Marcus det. on algae; MZUSP 379–381.

Description. Colony uniserial, rarely branched, white–translucent in color. Zooids oblong, boat-shaped, higher than wide, with lightly calcified walls; connective tubes short, the distal end of the zooid overlapping the proximal end of the subsequent zooid. Frontal membrane occupying the whole frontal surface. Marginal spines numbering 5–7 on each side, overarching the frontal membrane with only the most proximal pair directed outward; one pair of distal spines. One pair of pedunculate avicularia on distal corners of zooids, with rostrum hooked, mandible hard and curved. Ovicells absent.

Remarks. Beania cupulariensis was described from the Tortugas, Florida ( USA) by Osburn (1914). This species is characterized by zooids connected by short tubes, the distal ends of zooids overlapping the proximal ends of subsequent zooids, the frontal membrane overarched by 5–7 pairs of spines, with the most proximal pair directed to the outside, and one pair of distal spines. Harmer (1926, p. 419, pl. 28, figs 13–14) recorded two forms of B. cupulariensis . The first form, collected from the Philippines, has broader zooids with 7–9 pairs of uniformly spaced spines directed to the outside. An Indonesia form has longer and narrower zoecia, with 3–4 shorter pairs of marginal spines. These forms probably represent two distinct, undescribed species.

The number of tentacles found in Beania cupulariensis is variable: the Brazilian specimens have 26 tentacles ( Marcus 1955), but Cook (1985) reported polypides with 20–22 tentacles in material from Ghana; a figured specimen (ibid., fig. 37) also differs in lacking the most proximal pair of spines directed to the outside. It too may represent a different species.

Biological notes. The colonies of B. cupulariensis studied by us were collected from rocks in shallow water about 5 m deep ( Table 6), where the current flow is strong. Colonies from São Paulo state were found on mollusk shells and algae. Vieira et al. (2007) noted the association of this species with the bryozoan Vasignyella ovicellata (Catenicellidae) in northeastern Brazil. Osburn (1914, 1940) found some colonies of B. cupulariensis on dorsal surfaces of Cupuladria sp. from 18–40 m depth while the colonies reported by Marcus (1955) from the Brazilian coast were epiphytic on algae.

Distribution. Atlantic. Brazil: São Paulo ( Marcus 1944, 1955; present study) and Alagoas ( Vieira et al. 2007; present study); Porto Rico ( Osburn 1940); Curaçao (Fransen 1985); USA: Tortugas Island ( Osburn 1914);? Ghana ( Cook 1985).

Figures

FIGURES 2 – 7. SEM of uniserial species of Beania from the Brazilian coast. 2 – 4. Beania australis Busk, 1852, MZUSP 377, Alagoas state; 2, colony with four zooids; 3, close-up of a zooid; 4, lateral view of a zooid, note the basal connective tubes. 5 – 6, Beania cupulariensis Osburn, 1914, MZUSP 379, Alagoas state; 5, colony with three zooids; 6, close-up of a zooid, note the most proximal spine directed to the outside. 7, Beania klugei Cook, 1968, MZUSP 391, São Paulo state, small colony with three zooids.

FIGURES 18 – 23. Light micrography of uniserial species of Beania from the Brazilian coast. 18. Beania australis Busk, 1852, MZUSP 377, Alagoas state; 19. Beania cupulariensis Osburn, 1914, MZUSP 381, São Paulo state; 20. Beania klugei Cook, 1968, MZUSP 391, São Paulo state; 21. Beania maxilladentata Ramalho, Muricy & Taylor, 2010, MZUSP 400, Rio de Janeiro state; 22 – 23. Beania mirabilissima n. sp., MZUSP 405 (Holotype), São Paulo state; 22, colony; 23, lateral view of a zooid.

Tables

TABLE 1. Measurements (mm) of uniserial Beania species.

Beania australis	Beania cupulariensis	Beania klugei	Beania maxilladentata	Beania mirabilissima
Zooid length* Mean (St Dev) 1.04 (0.26)	0.89 (0.05)	0.93 (0.04)	0.91 (0.07)	1.34 (0.19)
Min–Max 0.77–1.32	0.81–0.98	0.87–1.03	0.80–1.05	1.12–1.71
Zooid width Mean (St Dev) 0.17 (0.01)	0.34 (0.01)	0.31 (0.02)	0.22 (0.01)	0.24 (0.01)
Min–Max 0.16–0.19	0.32–0.36	0.28–0.33	0.21–0.23	0.23–0.26
Frontal membrane Mean (St Dev) 0.51 (0.02)	0.77 (0.03)	0.76 (0.05)	0.66 (0.04)	0.68 (0.06)
Min–Max 0.49–0.54	0.74–0.80	0.70–0.83	0.57–0.69	0.59–0.87
Avicularia length Mean (St Dev) -	0.14 (0.01)	0.12 (0.01)	0.14 (0.02)	-
Min–Max -	0.13–0.16	0.11–0.13	0.11–0.16	-
*Including slender proximal tube.
Beania cupulariensis Osburn, 1914 (Figs 5, 6, 19; Table 1)