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 (
    94625, 94624, 94623, 94622, 94621, 94620, 
    94619, 94618, 94617, 94616, 94615, 
    94614, 94613, 94612, 94611, 94610, 
    94609, 94608, 94607, 94606, 94605, 
    94604, 94603, 94602, 94601, 94600, 
    94599, 94598, 94597, 94596, 94595, 
    94594, 94593, 95222, 95221, 95220, 
    95219, 94863, 94862, 94697
  ) 
  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 0.00119

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_prices range usergroup,product_id,lower_limit,usergroup_id usergroup 9 80 Using where

Result

product_id price
94593 1.69000000
94594 1.69000000
94595 1.69000000
94596 1.69000000
94597 1.69000000
94598 1.69000000
94599 1.69000000
94600 1.69000000
94601 1.69000000
94602 1.69000000
94603 1.69000000
94604 1.69000000
94605 1.69000000
94606 1.69000000
94607 1.69000000
94608 1.69000000
94609 1.69000000
94610 1.69000000
94611 1.69000000
94612 1.69000000
94613 1.69000000
94614 1.69000000
94615 1.69000000
94616 1.69000000
94617 1.69000000
94618 1.69000000
94619 1.69000000
94620 1.69000000
94621 1.69000000
94622 1.69000000
94623 1.69000000
94624 1.69000000
94625 1.69000000
94697 1.69000000
94862 1.69000000
94863 1.69000000
95219 1.69000000
95220 1.69000000
95221 1.69000000
95222 1.69000000