Seal member, turbine, and gas turbine

A seal member installed at a vane row constituted of a plurality of vanes disposed side by side in the circumferential direction of the axis of a turbine,

• wherein,
• the plurality of vanes comprises:
• a vane main body extending in the radial direction of the axis;
• an outer shroud installed at an outer end section in the radial direction of the vane main body;
• an inner shroud installed at an inner end section in the radial direction of the vane main body to form a main flow path of a combustion gas between the outer shroud and the inner shroud;
• and
• a retainer protruding from an inner surface in the radial direction of the inner shroud inward in the radial direction,
• the inner shrouds in the vanes which are adjacent to each other in the circumferential direction are adjacent to each other in the circumferential direction via a first gap,
• the vane main bodies in the vanes which are adjacent to each other in the circumferential direction are adjacent to each other in the circumferential direction via a second gap,
• the retainers in the vanes which are adjacent to each other in the circumferential direction are adjacent to each other in the circumferential direction via a third gap, and
• relative to one end of the seal member, the other end is positioned downstream in a direction along the axis in a direction of the combustion gas in the turbine, and thereby the seal member closes the third gap.