Reishia clavigera is a small, knobby rock snail from the rocky shores of East Asia, and it doesn't live in the United States. It is a predator that drills into or pries open barnacles, oysters, and other shellfish. Scientists know it well because ship-bottom paint made females grow male organs, so it became a warning sign of marine pollution.
Appearance
- Appearance
- A sturdy, spindle-shaped shell about 0.8–1.6 in (2–4 cm) tall, covered in rows of low knobs. Dark blotches around the knobs make most shells look blackish, and the opening is dark inside.
Where it lives
- Typical habitats
- Rocky shores
- Gravel shores
- Seawalls and breakwaters
- Range
- Coasts of Japan, Korea, China, and the Russian Far East, south to around the Malay Peninsula. It isn't found in the US.
- Preferred conditions
- Lives between the tides on rocks and stones, down to shallow water about 16 ft (5 m) deep.
Behavior
- Diet
- Barnacles, oysters, limpets, and other snails. It bores a hole with acid and its , or chips the edge of a shell and injects a toxin, which makes it a pest on oyster farms in Japan.
Life cycle
- Breeding season
- In early to midsummer, hundreds of snails may gather on shaded rock overhangs to lay eggs together.
- Clutch size
- Each small, stalked egg capsule holds roughly 130 eggs.
Name and classification
- About the name
- Older books and papers call it Thais clavigera.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
- Threats
- From the late 1900s, tin-based antifouling paint () on ships caused and population crashes in many areas of Japan and Korea. Some populations recovered after the paints were restricted.
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