Freshwater · Freshwater Molluscs · South Africa

Cape river mussel (Unio caffer)

Live Cape river mussel with hand for size. The Walsingham Farm, Kowie River, Eastern Cape (2022). Previously called Cafferia caffer. Large robust brown mussels. Posterior end of adult shell angular in outline. Juveniles show zigzag sculpture over the shell, as well as growth lines. Adults retain growth lines, but not sculpture. 87.3 x 46.6 mm.… Continue reading Cape river mussel (Unio caffer)

Bivalves · Marine Life

Sun oyster (Saccostrea cuccullata)

Sun oyster bed on a Natal rocky shore. Port St Johns, Wild Coast, Eastern Cape (2021) - iNaturalist Previously known as Crassostrea cuccullata. Also referred to as the Natal rock oyster. Lower valve deeply hollowed below the hinge and cemented to the rock. Upper valve relatively flat. Margins of both valves form a series of neatly… Continue reading Sun oyster (Saccostrea cuccullata)

Bivalves · Marine Life

Brown mussel (Perna perna)

Eroded and less eroded brown mussels in a bed. Old Woman's River, Eastern Cape (2018). Shell smooth and yellow-brown, sometimes tinged with green or with a chevron pattern. Specimens from crowded intertidal beds often very elongated and almost rectangular in cross-section. Submerged, fast-growing specimens are taller and narrower. Up to 125 mm. The dominant mussel… Continue reading Brown mussel (Perna perna)

Anemones · Cnidarians · Marine Life · South Africa

Crevice anemone (Anthopleura michaelseni)

Details of the spherules, and the long tentacles of the crevice anemone. Fishhoek, Western Cape (2020) - iNaturalist Also called long-tentacled anemone. Column with large sticky pads, to which shells and gravel adhere. Dark stripes usually radiate from mouth to the 96 long pink-to-brownish tentacles. Spherules present. Up to 150 mm in diameter, but commonly… Continue reading Crevice anemone (Anthopleura michaelseni)

Bivalves · Marine Life · South Africa

Mediterranean mussel (Mytilus galloprovincialis)

Mediterranean mussel bed surrounded by algae of all sorts. Yzerfontein, Western Cape (2020). Shell smooth, typically black or blue, shading to brown on the lower surface, but rarely light brown. Broad in cross-section and usually widest at base. Distinguished from Choromytilus meridionalis by pits in the resilial ridge. Up to 140 mm. Thought to be… Continue reading Mediterranean mussel (Mytilus galloprovincialis)

Bivalves · Marine Life

Ribbed mussel (Aulacomya atra)

Lone eroded mussel in a rock crevice. Hondeklipbaai, Northern Cape (2020) - iNaturalist Easily recognised by the strong wavy ridges running the length of the shell. Shell brown in juvenile, but becomes blue-black in larger individuals. Eroded areas are white. Up to 90 mm. Forms extensive beds low in the intertidal and on rocky reefs… Continue reading Ribbed mussel (Aulacomya atra)