SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    656, 658, 636, 657, 635, 596, 592, 519, 
    581, 458, 561, 425, 510, 424, 480, 360, 
    430, 395, 351, 289, 255, 242, 240, 30, 
    212, 194, 160, 159, 152, 429, 102, 34, 
    91, 90, 80, 31, 46, 428, 35, 488, 50, 51
  )

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "43.36"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": [
        "parent"
      ],
      "key": "parent",
      "used_key_parts": [
        "parent_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 73,
      "rows_produced_per_join": 73,
      "filtered": "100.00",
      "index_condition": "(`dbggbern`.`cscart_categories`.`parent_id` in (656,658,636,657,635,596,592,519,581,458,561,425,510,424,480,360,430,395,351,289,255,242,240,30,212,194,160,159,152,429,102,34,91,90,80,31,46,428,35,488,50,51))",
      "cost_info": {
        "read_cost": "36.06",
        "eval_cost": "7.30",
        "prefix_cost": "43.36",
        "data_read_per_join": "292K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ]
    }
  }
}