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 (
    431698, 431699, 431700, 431701, 431702, 
    431703, 431704, 431705, 431706, 431707, 
    431708, 431709, 431710, 431711, 431712, 
    431713, 431714, 431715, 431716, 431717, 
    431718, 431719, 431720, 431721, 431722, 
    431723, 431724, 431725, 431726, 431727, 
    431728, 431729, 431730, 431731, 431732, 
    431733
  ) 
  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 0.00226

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "100.92"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "range",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "key": "usergroup",
        "used_key_parts": [
          "product_id",
          "usergroup_id",
          "lower_limit"
        ],
        "key_length": "9",
        "rows_examined_per_scan": 72,
        "rows_produced_per_join": 72,
        "filtered": "100.00",
        "cost_info": {
          "read_cost": "86.52",
          "eval_cost": "14.40",
          "prefix_cost": "100.92",
          "data_read_per_join": "4K"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`webmarco`.`cscart_product_prices`.`lower_limit` = 1) and (`webmarco`.`cscart_product_prices`.`product_id` in (431698,431699,431700,431701,431702,431703,431704,431705,431706,431707,431708,431709,431710,431711,431712,431713,431714,431715,431716,431717,431718,431719,431720,431721,431722,431723,431724,431725,431726,431727,431728,431729,431730,431731,431732,431733)) and (`webmarco`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}