SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b53d759198b74ace18612597e48e8d4bfa58b7c1f36ae8df349751f7145b1da' 
  AND token = 'P+HZvRYVaZngvltwBFKwGOMc7QWjcvCU2n6Z4foZhGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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