Pirenella microptera (Kiener, 1842)

Figs 5 E–F

Cerithium microptera Kiener, 1842: 93 .

Cerithideopsilla microptera: Lozouet & Plaziat 2008: 110 –111, pl. 19, figs 8–10; Poppe 2008a: 284 –287, pl. 87, fig. 5. Cerithidea microptera: Thach 2005: 48, pl. 10 (in parts includes Pirenella incisa), figs 12, 16; Zvonareva et al. 2015: 8. Pirenella microptera: Reid & Ozawa 2016: 24 –27, figs 1, 2C, D, 6B, 7 (full synonymy).

Material examined. Nha Phu Bay, about 10 specimens.

Abundance. Uncommon.

Measurements. Up to 30 mm (Lozouet & Plaziat 2008).

Ecological notes. Development with planktonic phase of 10 to 12 days (Ozawa et al. 2015).

Dwells on bare mud bottom associated with outer to mid estuarine mangroves (Lozouet & Plaziat 2008). Appears to be generally rare over its wide range (Reid & Ozawa 2016).

In studied sites it was found on the mud surface under mangrove trees and on roots.

Relation to mangroves. Predominantly mangrove-associated.

Distribution in Vietnam. Northern-east coast, central coast, southern delta (Thach 2005; Reid & Ozawa 2016).

General distribution. From South China to Indo-Malayan area (Reid & Ozawa 2016).