SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '288324efb7d493abfb6035fa1727a903b8622daf12e428d17d4ccc074311523a' 
  AND token = 'gPprONqxoxotQFanBdt1pWXd80CQQNw+xc74816tzus=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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