Aconitum Used for Arrow Poison

Could you tell me which species of Monkshood has the most potent concentration of poison, and which was used to poison arrows?

The common aconite, known botanically as Aconitum napellus, is most often mentioned as a source of arrow poison used in former times. But other species were used also. For example, the Mu nationality of Yunnan, China, use Aconitum carmichaeli while the Aino of Japan use Aconitum japonicum. Aconitum ferox is the source of a Nepali poison called bikh, bish or nabee. It contains significant quantities of the alkaloid pseudaconitine, which has been called "the most deadly poison known". Aconitum palmatum yields another of the bikh poisons and Aconitum luridum, of the Himalayas, is said to be as virulent as that of A. ferox or A. napellus.
The roots typically were used to make arrow poison but all parts of the aconite plant are poisonous.
Which species of Aconitum is the most poisonous? I don't think that this question has been investigated because I was not able to find any scientific studies to answer your question.