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Chironomus zealandicus, commonly known by its Common midge or Non-biting Midge, is a insect of Chironomidae family.

Description
The Common New Zealand midge is a two winged non-biting Chironomus. These species are often confused with the biting mosquito as they look very similar. The males of this species have feathery antenna, and the females do not. The feathered antennas allow the insect to be able to walk in the water. The colouration of the species is black or dark segmented parts on the body (abdomen) with green or yellow stripping. Chironomus has three types of teeth in its mandible, one single strong apical tooth, three inner sub apical teeth and a single outer apicodorsal tooth. The mentum of Chironomus also has 15 darker pigmented teeth on outer sides and either sides of the teeth. The adult is approximately 5mm in length. The larvae form is blood red and has elongated blood gills on its penultimate abdominal segments

Natural global range
Chironomus are located in almost any fresh water environment globally, although normally in lakes and still water; these environments are preferred. They are especially found in great numbers in areas which are man made.

New Zealand range
Chironomus zealandicus is a native flying insect species of Chironomid that is only found in New Zealand. It was first reported by Hudson in 1892 and later was described taxonomically by Hutton in 1902 an Kieffer in 1921 with the name Chironomus novae zealandiae. In New Zealand, this species is mostly found in freshwater and lake areas in North Island and South Island, such as in Lake Ngaroto Hamilton, Lake Rotoroa, Lake Ellesmere Canterbury and other parts of South Island lakes and freshwaters.

Habitat preferences
Habit varies for this Midge species as it can handle several environments that are common in most areas. In New Zealand, the species is common in the lower reaches of the West Coast glaciers, geothermal waters and seashores. They also can be found in swarms in lake areas, swamps and stagnant waters where they breed. Futhermore fresh water rivers where there is side waters, pools and flow of a slow enough level they can be found as this can support life for all levels of reproduction. Overall the preffered habitat for the midge is slow staganant water such as lakes or ponds.

Life cycle/Phenology
The New Zealand midge Chironomidae, has 4 stages in its life cycle. This ranges from egg, larva, pupa and adult. The midge often breeds in swarms in areas of lakes and stagnent water which suits pupae and larvae to breed. Eggs are often laid in numbers up to 3000 and are contained in a gelatanous susbstance which helps it to attach to objects in the water such as sticks or to river or lake banks. The eggs which are not attatched to any material sink to the bottom but this does not stop the eggs ability to hatch instead it hatches on the bottom. The first stage (the egg) usually has a 2 to 7 days in which it hatches and then feed on the gelatanous material for a couple of days then burrowing into the substrate or the material availble for it to make its home. Most of the larval state is spent in tube constructed from the silt, they take on a red colour which is where they get the name blood worm from. They spend 2-7 weeks in this form which can be faster or slower due to current water temperatures caused by season weather. After they reach the end of this cycle they pupate which and the pupa atge lasts for up to 3 days where they emerge to the surface by actively swimming and stay on the surface for several hours until the adult form emerges. They then spend a maximum of 5 days as an adult as a result of not eatting at this stage, where they breed in swarms at night and then die. In the right conditions with regards to water temp and season in perfect condition the full life cycle can be completed within 2 weeks.

Diet and foraging
The New Zealand midge prefers stagnant slow water (swamps, lakes) and makes burrow in the sediment layer where as a pupa its lives in constructed tubes. The adult stage does not eat and this contributes to its short life; it is known as a non-biter unlike other mosquito’s type insects so does not feed. In undulations that it causes by using their 2-elongated blood gills this filter oxygen and nutrients past them in the water layer through the undulations. In New Zealand there is a wide range of strategies the midge uses as the fauna is so diverse. With this diversity in food selection it is able to get sources of nutirents from algae, detritus, associated microorganism, macrophytes, woody debri and invertabrites

Predators, Parasites, and Diseases
The midge from the larva, pupa and adult form is predated on by river fish and other aquatic vertebrates such as indigenous minnows. Examples of this are small trout which will come up and feed on the swarms above and on the surface of the water on warm nights. Other invertribrates such as anthropods are known to prey on midges, this is usually through chance due to swarms landing/ getting caught in their webs. Chironomus suffer deforming in the head capsules. According a recent study conducted by Jeyasingham & Ling has shown that the incidence of deformity increased during summer in Larvae, the cause to this incidence is season, genetic factors and sediment chemistry which may have caused problems to the deformity of the Chironomus capsule heads.

Other information
The worm like larvae known to fisherman and a common name as “blood worm” is red in colour due to the hemoglobin in the blood. The myoglobin that the worms has which is an iron and oxygen binding protein which helps them survive in habitats they are abundant in such as stagnent water; which has low oxygen. Blood worms often live in areas that suffer from pollution and as a result of its make up it can with stand these conditions unlike other midge species such as a green midge larvae related to it.