The Hemipterans (Order Hemiptera), commonly known as True Bugs, are a diverse order of insects recognized by their distinctive piercing or sucking mouthparts. They have hemimetabolous development – meaning newly hatched nymphs look like miniature wingless versions of the adults. They grow in size, normally moulting five times, with wings beginning to develop after the third or fourth moult. Adult hemipterans are usually equipped with two pairs of fully developed wings but, as with all of nature, there are exceptions and several species, including some found in the NWT, have half-developed wings (brachypterous) or no wings at all (apterous). The front wings are modified in different ways across the order from clear membranous to half-hardened to completely hardened and fused together.

Geographically, the NWT has an interesting composition of hemipteran fauna. Although there are no known endemic species, many reach the northern limits of their ranges in the southern quarter of the NWT whereas several others are only found in tundra or high arctic environments. Additionally, there are a number of species with primarily Palearctic distributions with ranges extending across Alaska, Yukon, and the NWT. This is a result of migration across the Bering land bridge.

Currently the order Hemiptera is separated into four suborders, of which three are found in North America and the NWT: Auchenorrhyncha (free-living hemipterans), Heteroptera (true bugs),  and Sternorrhyncha (phytophagous aphids and relatives). The Ternorrhyncha (plant-parasitic hemipterans) are not found here.

Sternorrhynchans are phytophagous and include aphids, whiteflies, and scale insects. The life histories of these species are diverse with many being complex, containing different forms and potentially multiple hosts while others are parthenogenic generalists. The aphids (Family Aphididae) are the most diverse family currently recorded in the NWT, representing about 20% of the currently known hemipteran species, with several more likely to be found. They also contain all the alien species of hemipterans reported from the NWT. Many of these species, as well as several native species, are known plant pests. We do not know yet what ecological impact their presence has on the NWT’s forests.

Auchenorrhynchans are also exclusively phytophagous and include leafhoppers, spittle bugs, tree hoppers, and the remarkable Canadian Cicada (Okanagana canadensis). Not only is this species the second-largest hemipteran found in the NWT, but where it has been spotted, in Sambah Deh Territorial Park is the farthest north a cicada has been recorded anywhere in the world.

The most diverse and numerous family of Hemipterans in the NWT is Cicadellidae, known as leafhoppers, representing about a quarter of the known NWT hemipteran species.

Heteropterans, known by their half hardened and half membranous forewings, vary the most in ecology out of the three hemipteran groups. The majority are phytophagous but several groups are omnivorous, predacious, or even parasitic. The plant bugs (Family Miridae) are the most diverse group. The NWT’s largest species of hemipteran is the adult giant water bug (Lethocerus americanus). This species is easy to spot as it can grow to over 5 cm long and will fly to new ponds in later summer. They are fierce predators of aquatic animals, including small fish and tadpoles. It is common in the extreme southern NWT and in the last 15 years this species been spotted further and further north as far as Yellowknife. This northward dispersal may be due to a warming climate.

Another interesting taxa are the shore bugs in the family Saldidae. They are predatory, hunting small arthropods largely on the shores of water bodies, including oceans. Several species have adapted to living along the coast of the Arctic Ocean including the Arctic shore bug (Chiloxanthus arcticus), which, in Canada, has only been recorded from the NWT.

There is still a great deal to learn about the hemipteran fauna of the NWT. Distribution data are lacking for many species, most of which only have a handful of records. There are likely many more hemipteran species yet to be found.

There are 391 species of hemipterans confirmed present in the NWT and at least two more species are expected to be present.