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 (
    60749, 60748, 60739, 60745, 60753, 60746, 
    60736, 60731, 60726, 60750, 60734, 
    61388, 60741, 60747, 60730, 60740, 
    61387, 60742, 61171, 60732, 60733, 
    60737, 61385, 60751
  ) 
  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 0.00149

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_prices",
      "access_type": "range",
      "possible_keys": ["usergroup", "product_id", "lower_limit", "usergroup_id"],
      "key": "product_id",
      "key_length": "9",
      "used_key_parts": ["product_id", "usergroup_id", "lower_limit"],
      "rowid_filter": {
        "range": {
          "key": "lower_limit",
          "used_key_parts": ["lower_limit", "product_id", "usergroup_id"]
        },
        "rows": 48,
        "selectivity_pct": 1.779095626
      },
      "rows": 48,
      "filtered": 100,
      "index_condition": "cscart_product_prices.lower_limit = 1 and cscart_product_prices.product_id in (60749,60748,60739,60745,60753,60746,60736,60731,60726,60750,60734,61388,60741,60747,60730,60740,61387,60742,61171,60732,60733,60737,61385,60751) and cscart_product_prices.usergroup_id in (0,1)"
    }
  }
}

Result