SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    2350, 2351, 2354, 2366, 2465, 2505, 2506, 
    2507, 2535, 2548, 2550, 2559, 2558, 
    2583, 2584, 2613, 2645, 2646, 2649, 
    2652, 2653, 2678
  ) 
  AND category_id != 414

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "37.46"
    },
    "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": 71,
      "rows_produced_per_join": 71,
      "filtered": "100.00",
      "index_condition": "(`s2cart`.`cscart_categories`.`parent_id` in (2350,2351,2354,2366,2465,2505,2506,2507,2535,2548,2550,2559,2558,2583,2584,2613,2645,2646,2649,2652,2653,2678))",
      "cost_info": {
        "read_cost": "30.36",
        "eval_cost": "7.10",
        "prefix_cost": "37.46",
        "data_read_per_join": "251K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`s2cart`.`cscart_categories`.`category_id` <> 414)"
    }
  }
}

Result

category_id parent_id
2352 2351
2353 2351
2355 2354
2359 2354
2363 2354
2364 2354
2367 2366
2368 2366
2508 2507
2509 2507
2513 2507
2515 2507
2516 2507
2518 2507
2528 2507
2529 2507
2530 2507
2532 2507
2533 2507
2534 2507
2536 2535
2537 2535
2538 2535
2539 2535
2540 2535
2541 2535
2543 2535
2544 2535
2545 2535
2546 2535
2547 2535
2549 2548
2554 2548
2551 2550
2552 2550
2553 2550
2555 2550
2556 2550
2557 2550
2560 2559
2562 2559
2563 2559
2564 2559
2565 2559
2566 2559
2567 2559
2568 2559
2569 2559
2570 2559
2572 2559
2573 2559
2574 2559
2575 2559
2576 2559
2577 2559
2578 2559
2579 2559
2580 2559
2581 2559
2582 2559
2647 2646
2648 2646