SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '728053f193c95e36a12865b43356b075ff3926ed184a2ca9673dc1840cb70a8d' 
  AND token = 'NtXb85f2ujOqhybw+qO7iw0wyjvWgFmJ6Itd5zX/3Rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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