SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    2375, 2379, 2382, 2386, 2423, 2427, 2437, 
    2438, 2444, 2457, 2461, 2467, 2484, 
    2502, 2599, 2624, 2637, 2650, 2654, 
    2672, 2674, 2676
  ) 
  AND category_id != 414

Query time 0.00077

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "47.36"
    },
    "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": 93,
      "rows_produced_per_join": 93,
      "filtered": "100.00",
      "index_condition": "(`s2cart`.`cscart_categories`.`parent_id` in (2375,2379,2382,2386,2423,2427,2437,2438,2444,2457,2461,2467,2484,2502,2599,2624,2637,2650,2654,2672,2674,2676))",
      "cost_info": {
        "read_cost": "38.06",
        "eval_cost": "9.30",
        "prefix_cost": "47.36",
        "data_read_per_join": "329K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`s2cart`.`cscart_categories`.`category_id` <> 414)"
    }
  }
}