SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4afc3816a84a8741b82bbac67e1d5b6143b0e82d78b16dbe901f7b305c757e1' 
  AND token = 'iPU4T15SAjk0y2JNffh/yZMXx4ZCo/yuHqB/GyaAAs8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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