SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'bca33e98e27823ec9b6c9e86d17548dd4300d98e3aa07ca95de5b56a4d9c65c6' 
  AND token = 'bX9OI1cfNrT0Y38sVacQTu+PWP+5l7KzzzsjO3IBVoU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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