SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24aba1296a3ea4be7503535793dd907f4d96d472895a8e887f3ebf2434007fd7' 
  AND token = 'YPmf6bY6BZbnQXBJQVfI3jqEr4qU2BszkUR/rFx4w9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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