SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54060c8dba1eb33bde9778f85785d0ace3690b6128b304617988432d0688b99b' 
  AND token = 'bn2ZAgaLxl9SGLBCGaqTKluWwe9lO5FcwY8iWqb3ITg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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