SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    457584, 458201, 432833, 453787, 443833, 
    415427, 446646, 427548, 448483, 459978, 
    456225, 448572
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00085

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.050171963,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_prices",
          "access_type": "range",
          "possible_keys": [
            "usergroup",
            "product_id",
            "lower_limit",
            "usergroup_id"
          ],
          "key": "usergroup",
          "key_length": "9",
          "used_key_parts": ["product_id", "usergroup_id", "lower_limit"],
          "loops": 1,
          "rows": 24,
          "cost": 0.04252208,
          "filtered": 50,
          "attached_condition": "cscart_product_prices.lower_limit = 1 and cscart_product_prices.product_id in (457584,458201,432833,453787,443833,415427,446646,427548,448483,459978,456225,448572) and cscart_product_prices.usergroup_id in (0,1)"
        }
      }
    ]
  }
}

Result

product_id price
415427 98.66000000
427548 1166.54000000
432833 604.64000000
443833 1640.04000000
446646 1003.10000000
448483 1691.53000000
448572 1418.58000000
453787 1943.68000000
456225 1995.30000000
457584 168.25000000
458201 1374.15000000
459978 622.29000000