Insects are reportedly experiencing widespread declines, but we generally have sparse data on their abundance. Correcting this shortfall will take more effort than professional entomologists alone can manage. Volunteer nature enthusiasts can greatly help to monitor the abundance of dragonflies and damselflies (Odonata), iconic freshwater sentinels and one of the few nonpollinator insect groups appreciated by the public and amenable to citizen science. Although counting individual odonates is common in some locations, current data will not enable a global perspective on odonate abundance patterns and trends. Borrowing insight from butterfly monitoring efforts, we outline basic plans for a global volunteer network to count odonates, including organizational structure, advertising and recruiting, and data collection, submission, and synthesis. We hope our proposal serves as a catalyst for richer coordinated efforts to understand population trends of odonates and other insects in the Anthropocene.

Collections of chironomid larvae, pupae, and adults were taken from the 1-m depth zone of 15 lakes of varying salinities in central British Columbia. Thirty-four species were identified.The littoral chironomid fauna of the lake series is divided into predominant associations whose existence seems to depend on salinity and productivity levels. A Cricotopus abanus – Procladius bellus association prevails in the lowest salinities (40 to 80 μmho/cm (1 mho = 1 S) conductivity) while in conductivities between 400 and 2800 μmho/cm a Glyptotendipes barbipes – Einfeldia pagana association predominates. In the most saline lakes (conductivity 4100 to 12 000 μmho/cm) a Tanytarsus gracilentus – Cryptotendipes ariel association is characteristic.Using these three chironomid associations it is possible to divide the 15 lakes into three groups. Waters with conductivities from 40 to 80 μmho/cm have chemical characteristics and a chironomid fauna distinct from those of higher salinities. The 10 lakes showing increasing conductivity (400 to 2800 μmho/cm) have physical, chemical, and biotic characters related to high productivity. In the particular case of this saline lake series, lakes with salinities about 3‰ (conductivity above 4000 μmho/cm) have a reduced productivity and a chironomid fauna characteristic of high salinities.

We describe the first dragonflies (Odonata: Anisoptera) from the early Eocene Okanagan Highlands of far-western North America from nine fossils. Six are assigned to five species in four new, named genera of Aeshnidae: Antiquiala snyderaenew genus and species, Idemlinea versatilisnew genus and species, Ypshna brownleeinew genus and species, Ypshna latipennatanew genus and species, and Eoshna thompsonensisnew genus and species; we treat one as Aeshnidae genus A, species A; one is assigned to Gomphidae: Auroradraco eosnew genus and species; and we treat a ninth, fragmentary fossil of unknown family affinity as Anisoptera indeterminate genus A, species A, which represents a seventh genus and eighth species. The dominance of Aeshnidae is consistent with other Paleocene and Eocene fossil localities. Auroradraco eos is the only fossil Gomphidae in the roughly 66-million-year gap between occurrences in mid-Cretaceous Burmese amber and the early Oligocene of France. Ypshna appears close to Parabaissaeshna ejerslevense from the early Eocene Fur Formation of Denmark; this is not surprising given Holarctic intercontinental connections at this time and a growing list of insect taxa shared between the Okanagan Highlands and the Fur Formation.

We describe the Cephalozygoptera, a new, extinct suborder of Odonata, composed of the families Dysagrionidae and Sieblosiidae, previously assigned to the Zygoptera, and possibly the Whetwhetaksidae n. fam. The Cephalozygoptera is close to the Zygoptera, but differs most notably by distinctive head morphology. It includes 59 to 64 species in at least 19 genera and one genus-level parataxon. One species is known from the Early Cretaceous (Congqingia rhora Zhang), possibly three from the Paleocene, and the rest from the early Eocene through late Miocene. We describe new taxa from the Ypresian Okanagan Highlands of British Columbia, Canada and Washington, United States of America: 16 new species of Dysagrionidae of the existing genus Dysagrion (D. pruettae); the new genera Okanagrion (O. threadgillae, O. hobani, O. beardi, O. lochmum, O. angustum, O. dorrellae, O. liquetoalatum, O. worleyae, all new species); Okanopteryx (O. jeppesenorum, O. fraseri, O. macabeensis, all new species); Stenodiafanus (S. westersidei, new species); the new genus-level parataxon Dysagrionites (D. delinei new species, D. sp. A, D. sp. B, both new); and one new genus and species of the new family Whetwhetaksidae (Whetwhetaksa millerae).

While climate change severely affects some aquatic ecosystems, it may also interact with anthropogenic factors and exacerbate their impact. In dry climates, dams can cause hydrological drought during dry periods following a great reduction in dam water discharge. However, impact of these severe hydrological droughts on lotic fauna is poorly documented, despite climate change expected to increase drought duration and intensity. We document here how dam water discharge was affected by climate variability during 2011–2018 in a highly modified watershed in northeastern Algeria, and how an endemic endangered lotic damselfly, Calopteryx exul Selys, 1853 (Odonata: Calopterygidae), responded to hydrological drought episodes. Analysis was based on a compilation of data on climate (temperature, precipitation, and drought index), water dam management (water depth and discharge volume and frequency), survey data on C. exul occurrence, and capture–mark–recapture (CMR) of adults. The study period was characterized by a severe drought between 2014 and 2017, which led to a lowering of dam water depth and reduction of discharge into the river, with associated changes in water chemistry, particularly during 2017 and 2018. These events could have led to the extirpation of several populations of C. exul in the Seybouse River (Algeria). CMR surveys showed that the species was sensitive to water depth fluctuations, avoiding low and high water levels (drought and flooding). The study shows that climate change interacts with human water requirements and affects river flow regimes, water chemistry and aquatic fauna. As drought events are likely to increase in the future, the current study highlights the need for urgent new management plans for lotic habitats to maintain this species and possible others.

The peatlands of the northern Cordillera of North America (consisting of the mountain ranges and intermontane lowlands and plateaus of British Columbia, Alberta, the Northwest Territories, the Yukon, and Alaska) support a distinctive Odonata fauna. Forty species in six families and 12 genera are typical of northwestern peatlands and another 12 species are occasional inhabitants of these environments. Of the 40 species, eight (20%) are peatland obligates and four (10%) almost always occur in such habitats. The remaining 28 (70%) are generalists and live in a wide range of aquatic habitats; nevertheless, they often are common inhabitants of, or are even dominant in, peatland environments. The fauna is dominated by the genera Aeshna Fabricius and Somatochlora Selys, with 11 and 10 species, respectively. It is also dominated by species restricted to Boreal regions (25 species, 62.5%), six (15%) of which have Holarctic distributions. The remainder of the fauna consists of eight species (20%) ranging transcontinentally in Transition Zone forests south of the Boreal Forest, five (12.5%) restricted to the Cordillera, and two (5%) with wide distributions in North America. Notes and maps summarize our knowledge of biogeographical information and previously unpublished records are listed. Significant southerly range extensions for species such as Coenagrion interrogatum (Hagen), Aeshna septentrionalis Burmeister, A. sitchensis Hagen, A. subarctica Walker, Somatochlora septentrionalis (Hagen), and Leucorrhinia patricia Walker are reported. Ecological and natural history data are outlined for each species. There do not appear to be any clear differences between the faunas of bogs and fens; dragonflies seem to respond to the habitat's form and structure rather than to its acidity or nutrient levels. Distinctive species associations result. A better understanding of the preferences of these dragonflies for different peatland microhabitats must await detailed research on oviposition behaviour and larval ecology.

Morphological, biological, and distributional data are presented for the four Canadian species of Mantispidae. A key for the identification of these species is provided. Climaciella brunnea (Say) is the most frequently collected Canadian species, occurring in southern British Columbia, Alberta, Manitoba, Ontario, and Quebec. Dicromantispa interrupta (Say) comb. nov. is given as a new combination for Mantispa interrupta Say; it is recorded in southern Ontario and Quebec. Dicromantispa sayi (Banks) occurs only in extreme southwestern Ontario. Leptomantispa pulchella (Banks) inhabits the dry Okanagan Valley of British Columbia; it is also known from Ojibway Prairie, Windsor, Ontario. The presence of the latter two species in Canada is published for the first time.Résumé-Nous présentons des données sur la morphologie, la biologie et la répartition des quatre espèces canadiennes de Mantispidae, ainsi qu'une clef pour leur identification. Climaciella brunnea (Say) est l'espèce canadienne la plus fréquemment récoltée et elle se retrouve dans le sud de la Colombie-Britannique, de l'Alberta, du Manitoba, de l'Ontario et du Québec. Dicromantispa interrupta (Say) comb. nov. est une nouvelle combinaison pour désigner Mantispa interrupta Say; l'espèce habite le sud du Québec et de l'Ontario. Dicromantispa sayi (Banks) se rencontre seulement dans l'extrême sud-ouest de l'Ontario. Leptomantispa pulchella (Banks) se retrouve dans la vallée sèche de l'Okanagan en Colombie-Britannique; elle a été récoltée aussi à Ojibway Prairie, Windsor, Ontario. La présence de ces deux dernières espèces au Canada est signalée pour la première fois.[Traduit par la Rédaction] Cannings and Cannings 544Can. Entomol. 138: 531-544 (2006)

Since Corbet’s thorough 1979 overview of Canadian Odonata, hundreds of regional works on taxonomy, faunistics, distribution, life history, ecology and behaviour have been written. Canada records 214 species of Odonata, an increase of 20 since the 1979 assessment. Estimates of unrecorded species are small; this reflects the well-known nature of the fauna. A major impetus for surveys and analyses of the status of species is the work of the Committee on the Status of Endangered Wildlife in Canada which provides a scientifically sound classification of wildlife species potentially at risk. As of 2017, six species have been designated “Endangered” and two “Special Concern” (only five of which are officially listed under the Federal Species at Risk Act (SARA)). The Order provides a good example of molecular barcoding effort in insects, as many well-accepted morphological species in Canada have been barcoded to some degree. However, more barcoding of accurately identified specimens of many species is still required, especially in most of the larger families, which have less than 70% of their species barcoded. Corbet noted that the larvae of 15 Canadian species were unknown, but almost all larvae are now well, or cursorily, described. Extensive surveys have greatly improved our understanding of species’ geographical distributions, habitat requirements and conservation status but more research is required to better define occurrence, abundance and biological details for almost all species.