SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d11666611cc641be804a0507522c1432a0a24cbc1cdbcd3d3f722206ce31fe8' 
  AND token = 'UAjG7pEZpKjodyXNISnS5Vpe4xaSP8gU2L5nwgfpU/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}