The Elongated Mussel (Modiolus elongatus) is a marine bivalve found in the warm, coastal waters of the northwest Pacific, especially around China and Hong Kong. It lives partly buried in soft sea floor sediments and anchors itself using strong threads called byssus.

Location:
Coastal waters of China, Hong Kong, and nearby areas in the northwest Pacific. Lives on soft seabeds, often in groups.

Average Size:
Adults usually grow to several centimetres in length, with long, narrow shells—although exact maximum size is not well known.

Family:
Mytilidae (the mussel family)

Species:
Modiolus elongatus

Ecological Role:
This mussel filters plankton and tiny particles from the water, helping to keep the environment clean. Its byssal “nest” also creates shelter for other sea creatures living in the seabed.

Movement and Sensory Features:
Elongated Mussels are mostly still. They don’t move around but stay fixed in place by their threads. They have very basic senses, mostly detecting changes in water through touch and chemical signals.

Reproduction:
Males and females release eggs and sperm into the water, where fertilisation happens. The young float in the sea as tiny larvae before settling on the seabed and growing into adult mussels.

Conservation Status:
Not currently listed as threatened. However, seabed damage from dredging or development may affect their habitats in some areas.

Collection Date:
Date unknown, collected in Salcombe.