SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '713b3baccd62dd2fab5a1436c84e1979fe6085fb642e8038045df4413b068967' 
  AND token = '7Mgxc7uAaGEJmwDxP9X2cVH6/ZqjQ2V3ufbTJcFZDEE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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