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 (
    10517, 10518, 10519, 10520, 10521, 10522, 
    10523, 10524, 10525, 10526, 10527, 
    10528, 10529, 10530, 10531, 10532, 
    10533, 10534, 10535, 10536, 10537, 
    10538, 10539, 10659, 10660, 10661, 
    10662, 10663, 10664, 10665, 10666, 
    10667, 10668, 10691, 10692, 10693, 
    10694, 10695, 10696, 10697, 10698, 
    10699, 10700, 10701, 10702, 10703, 
    10704, 10705
  ) 
  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 0.00134

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "34.06"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "range",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "key": "product_id",
        "used_key_parts": [
          "product_id"
        ],
        "key_length": "3",
        "rows_examined_per_scan": 49,
        "rows_produced_per_join": 9,
        "filtered": "20.00",
        "index_condition": "(`gaseus`.`cscart_product_prices`.`product_id` in (10517,10518,10519,10520,10521,10522,10523,10524,10525,10526,10527,10528,10529,10530,10531,10532,10533,10534,10535,10536,10537,10538,10539,10659,10660,10661,10662,10663,10664,10665,10666,10667,10668,10691,10692,10693,10694,10695,10696,10697,10698,10699,10700,10701,10702,10703,10704,10705))",
        "cost_info": {
          "read_cost": "33.08",
          "eval_cost": "0.98",
          "prefix_cost": "34.06",
          "data_read_per_join": "235"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`gaseus`.`cscart_product_prices`.`lower_limit` = 1) and (`gaseus`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}