SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    277, 245, 267, 228, 275, 219, 196, 223, 
    968, 166, 374, 378, 509, 270, 823, 269, 
    278, 483, 375, 487, 250, 376, 1025, 309, 
    203, 319, 377, 241
  ) 
  AND category_id != 264

Query time 0.00069

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "38.09"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "parent",
        "p_category_id"
      ],
      "key": "parent",
      "used_key_parts": [
        "parent_id",
        "category_id"
      ],
      "key_length": "6",
      "rows_examined_per_scan": 189,
      "rows_produced_per_join": 189,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "19.19",
        "eval_cost": "18.90",
        "prefix_cost": "38.09",
        "data_read_per_join": "493K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "((`aomnia_com`.`cscart_categories`.`parent_id` in (277,245,267,228,275,219,196,223,968,166,374,378,509,270,823,269,278,483,375,487,250,376,1025,309,203,319,377,241)) and (`aomnia_com`.`cscart_categories`.`category_id` <> 264))"
    }
  }
}