SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '252bb952ed5a97a3fd00b0e38721406eb50fc7f61d5300581307767c3efcb61b' 
  AND token = 'No+s7eZVUx4XFuDUxcXu4mGHTB8ILpzy9KpCLSHjA/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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