SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '944d7b9d443a7897b367139b03fd567f836ae961ae03697c3c96aed7acece08a' 
  AND token = 'FYxEEoaK2XMaztCsxUqoWcfQd7EuPO35dddCKATDAog=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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