SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    1224, 1216, 1219, 1217, 1218, 1215, 1220, 
    1221, 1226, 1228, 1225, 1230, 1229, 
    1227, 1231, 1234, 1232, 1233, 1236, 
    1235, 1237, 1238, 1241, 1242, 1240, 
    1239, 1243
  ) 
  AND category_id != 414

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "18.91"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "parent",
        "p_category_id"
      ],
      "key": "parent",
      "used_key_parts": [
        "parent_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 27,
      "rows_produced_per_join": 27,
      "filtered": "100.00",
      "index_condition": "(`s2cart`.`cscart_categories`.`parent_id` in (1224,1216,1219,1217,1218,1215,1220,1221,1226,1228,1225,1230,1229,1227,1231,1234,1232,1233,1236,1235,1237,1238,1241,1242,1240,1239,1243))",
      "cost_info": {
        "read_cost": "16.21",
        "eval_cost": "2.70",
        "prefix_cost": "18.91",
        "data_read_per_join": "95K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`s2cart`.`cscart_categories`.`category_id` <> 414)"
    }
  }
}