SELECT 
  q_product_prices.product_id, 
  MIN(
    IF(
      q_product_prices.percentage_discount = 0, 
      q_product_prices.price, 
      q_product_prices.price - (
        q_product_prices.price * q_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  q_product_prices 
WHERE 
  q_product_prices.product_id IN (
    37523, 37524, 37525, 37526, 37527, 37528, 
    37529, 37530, 37531, 37532, 37533, 
    37534, 37535, 37536, 37537, 37538, 
    37539, 37540, 37541, 37542, 37543, 
    37544, 37545, 37546, 37547, 37548, 
    37549, 37550, 37551, 37552
  ) 
  AND q_product_prices.lower_limit = 1 
  AND q_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  q_product_prices.product_id

Query time 0.00091

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "105.61"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "q_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": 54,
        "rows_produced_per_join": 10,
        "filtered": "19.99",
        "index_condition": "(`portal`.`q_product_prices`.`product_id` in (37523,37524,37525,37526,37527,37528,37529,37530,37531,37532,37533,37534,37535,37536,37537,37538,37539,37540,37541,37542,37543,37544,37545,37546,37547,37548,37549,37550,37551,37552))",
        "cost_info": {
          "read_cost": "103.45",
          "eval_cost": "2.16",
          "prefix_cost": "105.61",
          "data_read_per_join": "259"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`portal`.`q_product_prices`.`lower_limit` = 1) and (`portal`.`q_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}