SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    235, 198, 176, 178, 190, 255, 182, 175, 
    197, 236, 185, 191, 193, 199, 240, 179, 
    186, 174, 234, 194, 200, 180, 238, 202, 
    187, 181, 195, 177, 237, 196, 188, 254, 
    189, 263
  ) 
  AND category_id != 264

Query time 0.00149

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "36.67"
    },
    "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": 89,
      "rows_produced_per_join": 89,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "18.87",
        "eval_cost": "17.80",
        "prefix_cost": "36.67",
        "data_read_per_join": "232K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "((`twebezli_Commercemodalpopup`.`cscart_categories`.`parent_id` in (235,198,176,178,190,255,182,175,197,236,185,191,193,199,240,179,186,174,234,194,200,180,238,202,187,181,195,177,237,196,188,254,189,263)) and (`twebezli_Commercemodalpopup`.`cscart_categories`.`category_id` <> 264))"
    }
  }
}