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 (
    3464, 3459, 6950, 3470, 3457, 3462, 3450, 
    3458, 3463, 3451, 3445, 3472, 3481, 
    3482, 3475, 3483, 3474, 3473, 3426, 
    6949, 3427, 3477, 3452, 3478, 3479, 
    3453, 3491, 3488, 3497, 3495, 3489, 
    3492, 3496, 3490, 3494, 6951, 3502, 
    3503, 3493, 3498, 3428, 22, 23, 24, 3933, 
    3934, 3935, 1334, 1335, 1336, 1337, 
    1338, 1339, 1340, 1341, 1342, 1343, 
    1344, 1355, 1356, 1357, 1358, 1359, 
    1360, 1361, 1362, 1363, 1364, 3688, 
    3689, 3690, 3691, 3692, 3693, 3694, 
    3695, 3696, 3697, 3709, 3710, 3711, 
    3712, 3713, 3714, 3715, 3716, 3717, 
    3718, 3708, 3152, 25, 1365, 3138, 3149, 
    6719, 3146
  ) 
  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 0.00179

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "67.21"
    },
    "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": 96,
        "rows_produced_per_join": 19,
        "filtered": "19.99",
        "index_condition": "(`test2_gaseus`.`cscart_product_prices`.`product_id` in (3464,3459,6950,3470,3457,3462,3450,3458,3463,3451,3445,3472,3481,3482,3475,3483,3474,3473,3426,6949,3427,3477,3452,3478,3479,3453,3491,3488,3497,3495,3489,3492,3496,3490,3494,6951,3502,3503,3493,3498,3428,22,23,24,3933,3934,3935,1334,1335,1336,1337,1338,1339,1340,1341,1342,1343,1344,1355,1356,1357,1358,1359,1360,1361,1362,1363,1364,3688,3689,3690,3691,3692,3693,3694,3695,3696,3697,3709,3710,3711,3712,3713,3714,3715,3716,3717,3718,3708,3152,25,1365,3138,3149,6719,3146))",
        "cost_info": {
          "read_cost": "65.29",
          "eval_cost": "1.92",
          "prefix_cost": "67.21",
          "data_read_per_join": "460"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`test2_gaseus`.`cscart_product_prices`.`lower_limit` = 1) and (`test2_gaseus`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}