SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    7348, 7156, 7158, 7225, 7207, 7163, 7149, 
    7266, 7313
  ) 
  AND category_id != 1

Query time 0.00064

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "6.46"
    },
    "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": 31,
      "rows_produced_per_join": 31,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "3.37",
        "eval_cost": "3.10",
        "prefix_cost": "6.47",
        "data_read_per_join": "80K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_categories`.`parent_id` in (7348,7156,7158,7225,7207,7163,7149,7266,7313)) and (`nuie_scalesta_net`.`cscart_categories`.`category_id` <> 1))"
    }
  }
}

Result

category_id parent_id
7150 7149
7151 7149
7152 7149
7160 7149
7161 7149
7162 7149
7227 7149
7157 7156
7194 7156
7218 7156
7159 7158
7247 7158
7263 7158
7164 7163
7208 7207
7224 7207
7243 7207
7283 7225
7267 7266
7314 7313
7342 7313