Alderina smitti Osburn, 1950

Judith L Winston, 2016, Bryozoa of Floridan Oculina reefs, Zootaxa 4071 (1), pp. 1-81 : 13-15

Alderina smitti Osburn, 1950

( Fig. 5 ; Table 4 )

Membranipora irregularis: Smitt 1873: 8 , pl. 2, fig. 63; Osburn 1914: 194.

Alderina irregularis: Canu & Bassler 1928a: 27 , pl. 3, fig. 3, pl. 32, fig. 4; Hastings 1930: 708, pl. 3, figs 11–12; Osburn 1940: 363; Marcus 1941: 15, pl. 1, fig. 2.

Alderina smitti Osburn, 1950: 59 , pl. 6, fig. 2; Winston & Håkansson 1986: 11, figs 17–18; Winston & Vieira 2013: 106, fig. 4.

Material examined. VMNH no. 70602; USNM no. 1283230.

Description. Colony encrusting, unilamellar ( Fig. 5 A). Zooids oval to pyriform, the oval frontal membrane underlain by a depressed cryptocyst with one or more rows of aligned beads of calcification on its rim and a gymnocyst with small tubercles just outside the rim ( Fig. 5 B, C). Orifice indicated on distal wall skeleton by indentations. Large pore chambers can be seen on lateral walls of skeletal colonies ( Fig. 5 E, F). No avicularia. Ooecium transversely broad and narrow, with thickened crescents of calcification ( Fig. 5 D).

Remarks. Although descriptions of Alderina smitti by various authors do not mention lateral spines, Fig. 5 shows small calcified projections on the lateral and proximal gymnocyst just outside the cryptocystal rim that appear to be the remains of ephemeral spines ( Fig. 5 B, C. These spine bases can also be seen in the illustrations of the species in Winston & Håkansson (1986) and Winston & Vieira (2013).

Distribution. Tropical western Atlantic, Gulf of Mexico, and eastern Pacific.

Figures

FIGURE 5. Alderina smitti Osburn, 1950: A, entire small colony; B, zooids near colony origin; C, enlarged view of zooid, showing hollow spines; D, group of zooids, two with ooecia; E, distal interior of zooid; F, zooids at growing edge, showing pore chambers. Scale bars: A, 1 mm; B, E, 0.3 mm; C, F, 0.2 mm.

Tables

TABLE 4. Measurements in mm of Alderina smitti Osburn, 1950.

	Lz	Wz	Lo	Wo	Lop Wop	Lov	Wov
N	18	18	12	12	18 18	11	11
Mean	0.379	0.265	0.070	0.093	0.254 0.181	0.151	0.242
S D	0.034	0.028	0.009	0.007	0.041 0.031	0.022	0.027
Min	0.306	0.216	0.054	0.081	0.198 0.126	0.126	0.216
Max	0.450	0.306	0.081	0.108	0.396 0.234	0.180	0.306