National Museum of Natural Science

Silkworms can have many types of markings, which are easy to identify, making them good subjects for studying the genetics of domestic silkworms. The colors of silkworm markings mainly depend on the nature and distribution of pigments in the dermal cells and upper epidermis of silkworms. Before the 3^rd instar stage, there are no obvious markings. Markings do not become identifiable until after the 4^th instar stage.
Normal markings: These are the standard silkworm markings. In general, there are eye-shaped markings on the 2^nd thoracic segment and crescent-shaped markings on the 2^nd abdominal segment, as well as star-shaped markings on the 5^th abdominal segment.
Plain silkworms: The entire body is bluish white without markings.

The markings of silkworms～normal markings and plain silkworms