Toothed belt and manufacturing method therefor

A toothed belt, comprising:

• a back portion in which a tension member extending along a belt circumferential direction is embedded;
• a plurality of tooth portions formed on an inner circumferential surface of the back portion at intervals in the belt circumferential direction;
• a back rubber layer formed on a belt outer circumferential side with respect to the tension member;
• and
• a first rubber layer and a second rubber layer that are formed on a belt inner circumferential side with respect to the tension member, wherein
• the back portion includes the back rubber layer,
• an elastic modulus of the first rubber layer is larger than an elastic modulus of the second rubber layer,
• the first rubber layer comprises a first crosslinked rubber composition comprising a first rubber component and a first short fiber,
• a proportion of the first short fiber is 5 parts by mass to 60 parts by mass with respect to 100 parts by mass of the first rubber component,
• the first short fiber is oriented in a belt longitudinal direction along a contour of the tooth portion, and
• the tooth portion includes the first rubber layer and the second rubber layer that is interposed between the first rubber layer and the tension member.