The vector of the malarial parasite is the female Anopheles mosquito. This is because female Anopheles mosquitoes feed on the blood of humans and animals, and when they bite an infected person, they can transmit the malaria parasite from that person's blood to their own. The parasite then multiplies inside the mosquito, and when the mosquito bites another person, it can transmit the parasite to them, thus spreading the disease. It is important to note that male mosquitoes do not feed on blood, and therefore cannot transmit the malaria parasite.