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 (
    11285, 11284, 11283, 11282, 11254, 11242, 
    11227, 11226, 11210, 11208, 11198, 
    11193, 11105, 11103, 11101, 11100, 
    11096, 11083, 10538, 4303, 11070, 11196, 
    11197, 11190, 11191, 11192, 11194, 
    11187, 11188, 11189
  ) 
  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 0.00060

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "76.21"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "range",
        "possible_keys": [
          "membership",
          "product_id",
          "lower_limit",
          "membership_id"
        ],
        "key": "product_id",
        "used_key_parts": [
          "product_id"
        ],
        "key_length": "3",
        "rows_examined_per_scan": 33,
        "rows_produced_per_join": 6,
        "filtered": "19.99",
        "index_condition": "(`ea201_francemaqu`.`cscart_product_prices`.`product_id` in (11285,11284,11283,11282,11254,11242,11227,11226,11210,11208,11198,11193,11105,11103,11101,11100,11096,11083,10538,4303,11070,11196,11197,11190,11191,11192,11194,11187,11188,11189))",
        "cost_info": {
          "read_cost": "74.89",
          "eval_cost": "1.32",
          "prefix_cost": "76.21",
          "data_read_per_join": "158"
        },
        "used_columns": [
          "product_id",
          "price",
          "lower_limit",
          "usergroup_id",
          "percentage_discount"
        ],
        "attached_condition": "((`ea201_francemaqu`.`cscart_product_prices`.`lower_limit` = 1) and (`ea201_francemaqu`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}