Great-lakes
Guides
Agrilus pseudocoryli
hazel stem borer
Agrilus pseudocoryli is a metallic wood-boring beetle in the family Buprestidae, commonly known as the hazel stem borer. It develops within stems of hazelnut plants (Corylus spp.), where larval tunneling causes dieback. The species has been documented as a pest of hybrid hazelnut cultivars in the Great Lakes region, with damage severity varying by cultivar. Adult activity occurs from early June to mid-July.
Agrilus subcinctus
Native Ash Borer
Agrilus subcinctus, commonly known as the native ash borer, is a North American jewel beetle (Buprestidae) that develops in ash (Fraxinus) trees. Unlike the invasive emerald ash borer (A. planipennis), this species is restricted to dead ash twigs for larval development. Adults are active from late May through mid-August, with peak flight in June. The species serves as host for multiple hymenopteran parasitoids and has been studied for its distinct mating behavior, which involves visual aerial orientation followed by contact chemical signal evaluation.
Bythotrephes longimanus
Spiny Water Flea, Spiny Waterflea
Bythotrephes longimanus is a predatory planktonic cladoceran crustacean native to northern Europe and Asia that has become a significant invasive species in North America since its introduction to the Great Lakes in the 1980s. Adults reach up to 15 mm in length, with females growing substantially larger than males. The species exhibits cyclic parthenogenesis and produces distinctive morphological forms depending on reproductive mode and season. Its invasion has caused substantial ecological disruption through direct predation on native zooplankton and non-lethal effects that alter prey behavior and population dynamics.
Capnura manitoba
Manitoba snowfly
Capnura manitoba, commonly known as the Manitoba snowfly, is a small winter stonefly in the family Capniidae. It is one of several species in the genus Capnura, which are characterized by their cold-season activity patterns. The species was first described by Claassen in 1924 from Manitoba. Like other members of the Capniidae, it is adapted to cold-water environments and exhibits winter-emergence behavior typical of this stonefly family.
Drasteria graphica
Graphic Moth, Coastal Graphic
Drasteria graphica is a day-flying moth in the family Erebidae, found in coastal dune habitats along the Atlantic seaboard and Great Lakes shores. Adults have a wingspan of 30–35 mm and are active from May to August. The subspecies D. g. atlantica is listed as threatened in Connecticut.
Epischura lacustris
Epischura lacustris is a predatory calanoid copepod in the family Temoridae. It inhabits freshwater lakes across northeastern North America, including all five Great Lakes. The species exhibits size-selective predation on small zooplankton, particularly Bosmina longirostris, and has been observed to consume both phytoplankton and animal prey. It can be distinguished from other Great Lakes calanoids by three stout caudal setae on each caudal ramus and a noticeably bent urosome in mature specimens.
Hexagenia atrocaudata
Lake Hex
Hexagenia atrocaudata is a burrowing mayfly species in the family Ephemeridae, known from North American lakes and rivers. As a member of the common burrower mayflies, it spends the vast majority of its life as an aquatic nymph in bottom sediments, emerging as a short-lived winged adult for reproduction. Adults lack functional mouthparts and do not feed. Mass synchronous emergences can occur, producing swarms that attract fish and anglers alike. The species serves as an important indicator of clean freshwater ecosystems and provides substantial food resources for aquatic and terrestrial predators.
Hexagenia limbata
Giant Mayfly, Golden Mayfly, Big Michigan Mayfly, Great Leadwing Drake, Fishfly
Hexagenia limbata is a large burrowing mayfly native to North America, widely distributed across lakes and slow-moving rivers. Nymphs construct U-shaped burrows in muddy substrates and serve as important prey for fish and other aquatic predators. Adults emerge in synchronized mass events known as "hatches," living only 1–3 days without feeding, solely to mate and reproduce. The species is economically significant to sport fishing and serves as a bioindicator of clean freshwater ecosystems.
Hexagenia rigida
Great Olive-winged Drake
Hexagenia rigida is a burrowing mayfly (Ephemeroptera: Ephemeridae) native to North America. As a member of the common burrower mayfly genus, it spends most of its life as an aquatic nymph in lake and reservoir sediments, with adults emerging synchronously in large swarms. The species has a multi-year life cycle, typically requiring 3-4 years to complete development from egg to adult in northern climates. Laboratory studies indicate that larval growth and mortality are significantly influenced by food availability and density, with food limitation increasing size variation and mortality rates.
Lasiopogon tetragrammus
Great Lakes Sandpirate
Lasiopogon tetragrammus is a species of robber fly (Diptera: Asilidae) first described by Loew in 1874. The species was transferred from the bivittatus section to the tetragrammus group of the opaculus section in a 2020 molecular phylogenetic revision by Cannings. It is known by the common name Great Lakes Sandpirate, reflecting its geographic association with the Great Lakes region.
Melanoplus islandicus
island short-wing grasshopper, forest locust, island locust
Melanoplus islandicus is a spur-throated grasshopper in the family Acrididae, found in coastal regions of Alaska, Canada, and the Great Lakes area. Populations have declined due to habitat loss and invasive species, prompting conservation concern. The United States Fish and Wildlife Service proposed it for Endangered Species Act listing in 2003, though it remains unlisted.
Nannaria terricola
Loam-dwelling Twisted-Claw
Nannaria terricola is a flat-backed millipede in the family Xystodesmida, characterized by its loam-dwelling habits and the distinctive twisted, flattened claws on the anterior legs of males. The species is found in the Great Lakes region of the United States. Like other members of the genus Nannaria, it plays a role as a decomposer in forest ecosystems. The species was originally described as Fontaria terricola by Williams & Hefner in 1928 before being transferred to Nannaria.
Oecanthus laricis
Tamarack Tree Cricket, Laricis Tree Cricket
A small tree cricket endemic to the Great Lakes region of North America. Adults measure 13–15 mm with green forewings. The species produces one generation annually and is closely associated with tamarack (Larix laricina) and other coniferous trees.
Papaipema cerina
golden borer moth
Papaipema cerina, the golden borer moth, is a bright yellow noctuid moth found in the Great Lakes region of North America. Adults are active from September through mid-October. The species is uncommon to rare and is associated with diverse wetland and forest habitats. Larvae are borers that feed on lilies, May apple, and certain grass species.
Photinus indictus
Silent Firefly
Photinus indictus, commonly known as the silent firefly, is a diurnal firefly species in the beetle family Lampyridae. Adults are active during daylight hours and lack the bioluminescent lanterns characteristic of most fireflies, earning both its common name and specific epithet (Latin for "unspoken"). The species is found in eastern North America, particularly the Great Lakes region. Adults communicate through airborne pheromones rather than light signals.
Rhacognathus americanus
Rhacognathus americanus is a large predatory stink bug in the subfamily Asopinae, first described by Carl Stål in 1870. Adults measure 9–11 mm and exhibit dark brown to black coloration mottled with dull yellow. The species is native to North America but has not been collected or observed since 1966, with fewer than 40 verifiable sightings recorded throughout the entire 20th century. It is considered likely extirpated from Ontario and may be extinct across its range.
Scaphoideus lacyi
Scaphoideus lacyi is a leafhopper species in the family Cicadellidae, described by Barnett in 1977. It is native to eastern North America and has been recorded from Michigan, New York, Ohio, Ontario, and Québec. The species belongs to a genus that includes economically significant grapevine pests, though specific information about S. lacyi's biology and ecology remains limited in available sources.
Schizocosa aulonia
Schizocosa aulonia is a wolf spider species described by Dondale in 1969 from the Great Lakes region. It is closely associated with beach and sand dune habitats in northeastern Illinois. The species resembles S. retrorsa, with which it shares morphological similarities.
Trimerotropis huroniana
Lake Huron Locust, Great Lakes Grasshopper
A band-winged grasshopper endemic to the Great Lakes region, restricted to open dune habitats along the shores of Lakes Huron, Michigan, and Superior. Body length ranges from 24–40 mm with females larger than males. Adults are active from late July through August. Federally listed as Threatened in Canada under the Species At Risk Act, with approximately 10 known sites remaining in Ontario.
Xylesthia
Xylesthia is a genus of wall spiders in the family Oecobiidae, a group of small arachnids known for constructing flat, tangled webs on vertical surfaces such as walls, rocks, and tree trunks. These spiders are characterized by their compact bodies, relatively long legs, and distinctive spinneret arrangement. The genus is poorly documented in North American faunal surveys, with most species described from other regions. The 'n-sp' designation indicates an undescribed or unidentified species within the genus.