what is a blod worm?

Question

it lives in bottom of the stream, in mid its group is insect

Answer 1

Blood Worms or Black Worms? Blood worms are really the larval form of one of the chironomid midges -- insects rather than worms. You could compare them with the transparent glass worms. California blackworms, on the other hand, are a cousin to earthworm worms.

Origins: Blood worms grow wild in ponds, pools, and lakes. We even find their tubes in aquaria that have set unused for a period of time. Blood worms live in the mud. Glassworms swim in the water. Both can produce huge swarms.

Appeal: Fish love the taste of blood worms – even the pickiest eaters. The hemoglobin that colors them red is an excellent iron source.

Size: Full-grown blood worms grow to about an inch. Their size makes them ideal for two to six-inch fish. Once they pupate, the smaller fish sometimes have trouble eating them.

Adults. Looking very much like mosquitoes, the non-biting parents lay their eggs in water and flit off. Adults live three to five days.

Answer 2

You might have better luck in the science section.

But I feed my freshwater aquarium pals frozen bloodworms--mine are mosquito larvae. You can get them dried, too. Technically, mosquitoes are flies--family Diptera. But I don't know that every "bloodworm" is necessarily a mosquito larva. The term might refer to other stuff, like, say, parasites that live in blood inside mammals or something. But that's a whole 'nother group, not insects at all.