Ibn al-Qasim led an Alid rebellion in Talaqan[1][2] in the year 219 AH (834 CE), during the days of the Abbasid Caliphate of Al-Mu'tasim.
However, Al-Asili Fi Ansab At-Talibiyeen mentions that the descendants of Qasim(whose only son was Muhammad Al-Sufi) continue up to this day.
Here is the text from Al-Asili Fi Ansab At-Talibiyeen: Ali al-Asghar bin Umar al-Ashraf had offspring from three of his children: 1.
In al-Mabsoot it is stated that "his lineage descended from three men: al-Qasim, Umar al-Shajari and Abu Muhammad al-Hasan.".
[5] Also Ibn Inabah, perhaps the most famous scholar in the field of Talibid genealogy finds a clan from amongst his descendants in Al-Faiz in Karbala and he mentions their ancestry.