Answer:
valved ostia
Explanation:
In insects body fluids are drawn into the valved ostia. There are usually 13 pairs of ostia present. These are arranged with ostial valves. The valved ostia are  the openings located with the length of heart and aorta organ. The circulating fluid is known as haemolymph. The peristaltic movement causes haemolymph pumping. These originates from the posterior side of the insect body.
