SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bfad5e0ce96f71de200c732097a84d802882ec9b5170ce4f08c8844469d3e69' 
  AND token = 'JmeYCeLSSp1PaDsaAjQh61PghpmxnHGrZOqU89YtKos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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