SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '573e309e94de2849b5dcbea8aead3a3ca25aa9303620a7b950373407e27b0f5f' 
  AND token = 'yEAnQd6TO/PgITYmlxaWMEUahyRyLOkfbS3E3wKEBTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00078

JSON explain

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