Cupuladria biporosa Canu & Bassler, 1923

Judith L Winston, 2016, Bryozoa of Floridan Oculina reefs, Zootaxa 4071 (1), pp. 1-81 : 21-24

Cupuladria biporosa Canu & Bassler, 1923

( Fig. 11 , Table 10 )

Membranipora canariensis: Smitt 1873: 10 , pl. 2, figs 69–71.

Cupuladria biporosa Canu & Bassler, 1923: 29 , pl. 47, figs 1–2; Cook 1965: 203, pl. 1, figs 2A, B, 3A, B, 4A, B, 5, 6 A, B, text-fig. 1, g-j; Winston 2005: 13, figs 30, 37.

Cupuladria canariensis: Canu & Bassler 1928a: 16 (part), text-fig. 2; Marcus & Marcus 1962: 285, pl. 1, figs 1–2; Lagaaij 1963b: 225 (part), pl. 26, figs 4, 5.

Cupuladria sp. Cheetham & Sandberg 1964: 1021.

Material examined. VMNH no. 70611, 70612; USNM no. 1283236.

Description. Saucer-shaped colonies, free-living on surface of sandy substrata, up to 16 mm diameter; many colonies broken through predation or physical disturbance; irregular fragments regenerating to repair missing areas and continuing to grow. Convex upper surface of the colony consisting of rows of radially arranged zooids ( Fig. 11 A–D). Autozooids rhomboidal, with frontal membrane underlain laterally and proximally by granular cryptocyst. At distal end of each zooid an interzooecial vibraculum with an ear-shaped chamber ( Fig. 11 C, D) and a mandible in the form of a long curved seta. Large vicarious vibracula, with scimitar-shaped setae occur in ancestrular region at apex of colony or in areas of regeneration. Lower surface of the colony consisting of extrazooidal calcification, which forms concentric rings, divided into small square sectors, each with 1-6, mostly 2- 4, round pores ( Fig. 11 E, F). No ooecia. Embryos brooded in zooids.

Remarks. Three cupuladriid species are common along the continental shelf from Cape Hatteras to Florida according to the study of Maturo (1968). The two smaller species, Cupuladria doma and Discoporella depressa , occur across the entire shelf, but Cupuladria biporosa was found only on the outer part of the shelf. Their occurrence in Oculina rubble may represent a death assemblage as no colonies found had been alive when collected, but sediment samples from the Florida shelf generally contain a large number of dead, relative to living, colonies of cupuladriids, so the species may well be part of the Oculina reef community.

Distribution. Cape Hatteras to Brazil, Caribbean, Gulf of Mexico.

Figures

FIGURE 11. Cupuladria biporosa Canu & Bassler, 1923: A, frontal and basal views of colony fragments; B, growing edge of colony; C, autozooids and vibracula; D, close-up showing vibracular chambers; E, basal view of colony fragment, showing patterning of square sectors with round pores; F, close-up of several sectors with 4 pores. Scale bars: A, E, 1 mm; B, C, 0.5 mm; D, F, 0.3 mm.

Tables

TABLE 10. Measurements in mm of Cupuladria biporosa Canu & Bassler, 1923.

	Lz	Wz	Lop	Wop	Lav	Wav
N	18	18	18	18	18	18
Mean	0.538	0.313	0.315	0.190	0.220	0.133
SD	0.029	0.023	0.032	0.021	0.012	0.021
Min	0.450	0.288	0.252	0.162	0.198	0.090
Max	0.576	0.378	0.396	0.234	0.234	0.162