SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2ff3df21ca7a68f0f1339f526605a00ed22644fd32f00122a1d8a06c433655f' 
  AND token = 'Nqdwpg9IZxOx1xoWd9Ryr1WL6iGycC1HKAUAHn/FOHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}