SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2addfefabaa36f2847bb94ced6778afb417e7a4fbb1acc53c8025571ae19af05' 
  AND token = 'qCRzYHKiU/6+K+oMmyRU0t6kYWuSacK0BYgxdNZPO1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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