SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81c4225d60d173da1d6bee96c5ac5bf9c24fc7f513194cc88cc11fa2c520f479' 
  AND token = 'aoQQc4QCqpUNIeAdKyEPHUqLuJMFR55ZTXRQ4KO/ktw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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