SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba2b02c66c7e416a1a28c4d570e7d04cab89e7c968d63fd190167be183688322' 
  AND token = 'EX5XDlX4xnzdMGjgxi7WsIpEiEZWpx+AuehHIn2fPkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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