The buttocks (Nitimba) and the elevating marmas (Utkṣepa) are classified as those that cause death after some time; the Stapanī is also indicated as a Vishalyaghna marma.
english translation
नितम्ब और उत्क्षेप ये कालान्तरप्राणहर होते हैं; स्थपनी भी विशल्यघ्न मर्म हैं।