SELECT 
  product_prices.product_id, 
  MIN(
    IF(
      product_prices.percentage_discount = 0, 
      product_prices.price, 
      product_prices.price - (
        product_prices.price * product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  product_prices 
WHERE 
  product_prices.product_id IN (
    79101, 110786, 82833, 90455, 93376, 
    74090, 74149, 74085, 74088, 74067, 
    134857, 80049, 74070, 74092, 74133, 
    74118, 74075, 120752, 78989, 79406, 
    74072, 74073, 79483, 84003, 74131, 
    150621, 168902, 74127, 74077, 92925, 
    74116, 74120, 74102, 74148, 74071, 
    74097, 74093, 74076, 150705, 74105, 
    74130, 98283, 136372, 74084, 74100, 
    74139, 74086, 74135
  ) 
  AND product_prices.lower_limit = 1 
  AND product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  product_prices.product_id

Query time 0.00556

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "53.05"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "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": 75,
        "rows_produced_per_join": 7,
        "filtered": "10.00",
        "index_condition": "(`goimagine`.`product_prices`.`product_id` in (79101,110786,82833,90455,93376,74090,74149,74085,74088,74067,134857,80049,74070,74092,74133,74118,74075,120752,78989,79406,74072,74073,79483,84003,74131,150621,168902,74127,74077,92925,74116,74120,74102,74148,74071,74097,74093,74076,150705,74105,74130,98283,136372,74084,74100,74139,74086,74135))",
        "cost_info": {
          "read_cost": "52.30",
          "eval_cost": "0.75",
          "prefix_cost": "53.05",
          "data_read_per_join": "179"
        },
        "used_columns": [
          "id",
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`goimagine`.`product_prices`.`lower_limit` = 1) and (`goimagine`.`product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}