SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2773ac45daf6359eb0f24a45358007ba3fbd445cae6ca60b11eeff510eb56d4' 
  AND token = '9a+ofnDYfVyWpE6ylKXuyF6vOgUWzkGVjub73/F1BhE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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