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.