SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e86d73890757362d93881ff25b661e0fc75d27db2685127bf34e7547854e18c4' 
  AND token = '/epwCg/7loLQrR59IqFP5Rg7wnnGSutyFknLO1JOuYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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