Pteria penguin – Winged Pearl Oyster with Blister Pearl - Height: 140 cm - Width: 90 cm- 61 g - (1)

Pteria penguin – the winged oyster and its pearl

Specimen of Pteria penguin (Röding, 1798), a bivalve mollusk belonging to the family Pteriidae, known as the winged pearl oyster for the particular shape of its shell. The specimen, indicated as originating from Japan, preserves a valve with an intensely nacreous inner surface, on which develops a hemispherical nacreous formation, commonly called a blister pearl or mabé.

The most evident characteristic of Pteria penguin is the strongly asymmetric shape of the shell. One end develops into a wide rounded expansion, while the other narrows, forming an elongated structure that resembles a wing. This geometry distinguishes the species from the winged pearl oysters of the genus Pinctada, generally characterized by more rounded valves.

The inner surface presents a broad area of mother-of-pearl in silver, ivory and gold tones, pierced by pink, green and blue reflections that change according to the angle of observation. A dark, almost black, band follows the margin of the valve and creates a clear contrast with the central nacreous region.

In the upper part of the shell there is a rounded formation, with a smooth and glossy surface and a warm coloration, ranging between honey, bronze and golden brown. Its shape is that of a small dome that emerges directly from the inner surface of the valve.

This structure belongs to the category of nacreous formations adherent to the shell, different from free pearls that develop in the soft tissues of the animal. The term blister pearl indicates a nacreous formation attached to the inner surface of the shell; mabé is instead used mainly for hemispherical pearls obtained through specific cultivation techniques.