Hiatella rugosa. Ruby, red, and orange siphon tips protruding from limestone. Menai Strait, April 2011. Species Hiatella rugosa Photographer / copyright holder I.F. Smith
Hiatella rugosa. Siphon tips protruding from limestone. Specimen on right has siphons closed while they are expanded to brace against sides of hole during boring activity. Small burrows with mud tube extensions made by Polydora worms. Menai Strait Species Hiatella rugosa Photographer / copyright holder I.F. Smith
Hiatella rugosa. Dorsal (except smallest) view of specimens extracted from limestone borings. Menai Strait, April 2011. Species Hiatella rugosa Photographer / copyright holder I.F. Smith
H. rugosa. Mantle lobes sealed except for small opening for foot; sucker-like. Top left: tip of foot showing, and rounded anterior gape of shell resembles Zirfaea crispata. Bottom left; emitting milt as temperature rose during photography. Menai Strait. Species Hiatella rugosa Photographer / copyright holder I.F. Smith
Hiatella rugosa in situ in limestone boring, rock split open. b: lower face of narrow outer boring, bored when juvenile. s: siphon tip of neighbouring specimen projecting from rock surface. Menai Strait, April 2011. Species Hiatella rugosa Photographer / copyright holder I.F. Smith
Hiatella rugosa. Periostracum covers siphons, and much survives on valves; difficult to explain if boring action into solid limestone is by mechanical movement of valves unaided by chemical or muscular action of foot. Species Hiatella rugosa Photographer / copyright holder I.F. Smith