Conservation-concern
Guides
Cybistrinae
Cybistrinae is a subfamily of predaceous diving beetles within Dytiscidae, comprising 12 genera and approximately 130 described extant species. Members are large-bodied aquatic beetles distributed across multiple continents, with notable diversity in the Neotropical region and Japan. The subfamily is characterized by distinctive larval and adult morphological features, including specialized tarsal structures and genitalia. Several species are of conservation concern, including critically endangered populations in Japan.
Dichagyris acclivis
Inclined Dart
Dichagyris acclivis, commonly known as the Inclined Dart, is a noctuid moth native to central and eastern North America. The species is of conservation concern in parts of its range, notably listed as a species of special concern in Connecticut. Adults are active in late summer and early autumn, with larvae specializing on seeds of switchgrass (Panicum virgatum).
Digrammia equivocata
equivocal looper
Digrammia equivocata, the equivocal looper, is a moth species in the family Geometridae. It was described by Douglas C. Ferguson in 2008 and is native to North America. The species is listed as historic in Massachusetts and as a species of special concern in Connecticut. Its larval host plant is Tephrosia virginiana.
Dinacoma sanfelipe
Dinacoma sanfelipe is a melolonthine scarab beetle endemic to southern California, described in 2020 as the first new species in the genus in 90 years. The genus Dinacoma is restricted to California and contains cryptic species that are difficult to distinguish. One congener (D. caseyi) is federally listed under the U.S. Endangered Species Act, and all known species in the genus may be of conservation concern.
Drasteria occulta
occult drasteria moth, Occult Graphic
Drasteria occulta is a small erebid moth first described by Henry Edwards in 1881. It is known from coastal areas in the eastern and southern United States, with scattered records from Maine to Texas. The species has experienced significant regional decline and is considered extirpated in Connecticut. Larvae are specialized feeders on Vaccinium species.
Eacles imperialis nobilis
Texas Imperial Moth
Eacles imperialis nobilis is a variety of the Imperial moth, commonly known as the Texas Imperial Moth. As a member of the giant silk moth family Saturniidae, it is a large, nocturnal species with vestigial adult mouthparts and larvae that feed on diverse woody vegetation. The variety designation suggests geographic differentiation within the broader Eacles imperialis complex, which ranges from Canada to Argentina. Like other Imperial moth populations, this variety faces threats from light pollution, habitat destruction, pesticides, and introduced parasitoid flies.
Efferia coulei
Northwestern Hammertail
Efferia coulei is a robber fly (family Asilidae) described by Wilcox in 1966. It occurs in the grasslands of southern British Columbia, Canada, particularly the Okanagan Valley, where it is sympatric with its closest relative Efferia okanagana. The two species are genetically distinct, with approximately 7.0% divergence in cytochrome oxidase I (COI) DNA barcode sequences. As a member of the Efferia arida species group, it shares morphological affinities with E. arida and E. pinali.
Efferia okanagana
Okanagan Hammertail
Efferia okanagana is a species of robber fly (family Asilidae) described in 2012 from the grasslands of southern British Columbia, Canada. It belongs to the E. arida species group and is most closely related to E. arida and E. pinali. The species has a restricted distribution centered on the Okanagan Valley and is considered potentially at risk by COSEWIC.
Elachista
grass-miner moths, typical grass miner moths
Elachista is a large genus of very small gelechioid moths, the type genus of the family Elachistidae. These grass-miner moths are characterized by reduced, "feathery" hindwings and typically display one to three light transverse bands on the forewing uppersides. The genus has a near-cosmopolitan distribution, being absent only from very cold regions and some oceanic islands, with highest diversity in the Palearctic. Taxonomic complexity includes numerous undescribed species, cryptic species complexes, and disputed subgeneric classifications.
Elachistinae
grass-miner moths
Elachistinae is a subfamily of small moths in the family Elachistidae, superfamily Gelechioidea. The subfamily contains approximately 805 valid species placed in 10 genera, with the genus Elachista being the most diverse. Species are predominantly leaf miners, with larvae feeding on monocotyledonous plants, especially sedges (Cyperaceae) and grasses (Poaceae). The subfamily has a worldwide distribution with significant diversity in the Holarctic region. Many species show narrow host plant associations and some exhibit vicariant distribution patterns.
Ellipes
pygmy mole crickets
Ellipes is a genus of pygmy mole crickets (Orthoptera: Tridactylidae) containing small, fossorial insects. Most tridactylids inhabit moist margins of ponds and streams, but some Ellipes species have independently evolved to occupy xeric scrub and sandhill habitats. The genus includes at least six described species distributed across North and South America, with several Florida endemics exhibiting restricted ranges and limited study due to their minute size and cryptic habits.
Ellipes deyrupi
Deyrup's Pygmy Mole Cricket
Ellipes deyrupi is a recently described species of pygmy mole cricket endemic to the northern Lake Wales Ridge of Florida. It represents one of at least two independent lineages of tridactylids that have adapted to xeric scrub and sandhill habitats, diverging from the ancestral aquatic or semi-aquatic lifestyle typical of the family. The species is sympatric with Neotridactylus archboldi at all known locations but has not been found co-occurring with its congener Ellipes eisneri. Its restricted geographic range and specialized habitat requirements raise conservation concerns.
Ellipes eisneri
Eisner's Pygmy Mole Cricket
Ellipes eisneri is a pygmy mole cricket endemic to Florida, described by Deyrup in 2005. Unlike most tridactylids, which inhabit moist edges of ponds and streams, this species has adapted to xeric scrub and sandhill habitats in sandy uplands. It has a restricted geographic range and has not been found co-occurring with its close relative Ellipes deyrupi, despite both species sharing convergent ecological habits. The species is poorly studied and difficult to collect due to its small size.
Ellipsoptera lepida
Ghost Tiger Beetle, Little White Tiger Beetle
Ellipsoptera lepida, known as the ghost tiger beetle or little white tiger beetle, is a small tiger beetle notable for its almost pure white dorsal coloration that provides exceptional camouflage on pale sandy substrates. Adults measure 9–11 mm and are active during summer months. The species occupies a specialized niche in deep, dry sand habitats and has a two-year life cycle. Populations are localized and patchy across its range, and it has disappeared from many historical sites due to habitat succession and revegetation. It is listed as a state threatened species in Minnesota.
Enallagma recurvatum
Pine Barrens Bluet, Pale Barrens Bluet
Enallagma recurvatum is a small damselfly endemic to the United States. It inhabits freshwater lakes, particularly in pine barrens and similar sandy, acidic lake systems. The species is considered threatened due to habitat loss from development, water quality degradation, and shoreline alteration. Its restricted range and specialized habitat requirements make it vulnerable to environmental changes.
Ephyriades brunnea
Florida Duskywing, Florida duskywing skipper
Ephyriades brunnea is a skipper butterfly endemic to South Florida, restricted to pine rockland habitats. The species has experienced noticeable population declines in recent years and is listed as a Species of Greatest Conservation Need in Florida. Adults have a wingspan of approximately 48 mm and exhibit sexual dimorphism in wing pattern. Larvae feed exclusively on Barbados cherry (Malpighia emarginata), while adults nectar on wild coffee and other flowering plants.
Eristalis cryptarum
Bog-dwelling Drone Fly, Bog Hoverfly
Eristalis cryptarum is a Holarctic hoverfly species specializing in bog and wetland habitats. It is notable for its restricted distribution and significant population declines across Europe, with extirpation from much of its former English range and critical endangerment in Denmark. The species exhibits classic Eristalis morphology with distinctive coloration and is a member of the drone fly group, though it is not a bee mimic to the same degree as some congeners. Its larvae are assumed to be aquatic filter-feeders in saturated peat, though they remain undescribed.
Erynnis brizo
Sleepy Duskywing, Banded Oak Duskywing
Erynnis brizo is a skipper butterfly in the family Hesperiidae, found throughout North America. Adults are commonly confused with E. juvenalis and E. lucilius. The species is listed as threatened in Connecticut and Maine. Larvae feed on scrub oaks, while adults nectar from heath family flowers and other sources.
Erynnis martialis
Mottled Duskywing
Erynnis martialis, the mottled duskywing, is a small skipper butterfly in the family Hesperiidae. It occurs across much of the eastern United States and parts of southern Canada. The species is closely associated with oak savanna habitats and has experienced significant population declines due to habitat loss and fragmentation. It is listed as a species of special concern in Connecticut, where it is believed extirpated.
Euchloe
Dappled Whites, Marbles
Euchloe is a genus of pierid butterflies in the tribe Anthocharini with a Holarctic distribution spanning Europe, Central Asia, and North America. Old World species are commonly called dappled whites, while New World species are known as marbles. The genus includes approximately 30 described species, with several exhibiting narrow endemic ranges and conservation concern. Some species demonstrate remarkable camouflage abilities through background matching and wing-folding behavior.
Euctenizidae
Wafer-lid Trapdoor Spiders
Euctenizidae is a family of mygalomorph spiders elevated from subfamily status in 2012. The family contains approximately 79 described species across eight genera, including Aptostichus, Myrmekiaphila, and Promyrmekiaphila. Members are characterized by their fossorial lifestyle and construction of silk-lined burrows with distinctive trapdoors. The family is now considered more closely related to Idiopidae than to other trapdoor spider families.
Eunota fulgoris erronea
Willcox Tiger Beetle
Eunota fulgoris erronea is a subspecies of tiger beetle endemic to the Willcox Playa area of the Sulphur Springs Valley in southeastern Arizona. Formerly placed in the genus Habroscelimorpha, this taxon is now classified under Eunota following molecular phylogenetic revisions. It is considered a classic example of a geographically restricted tiger beetle with striking coloration and intricate white elytral markings. The subspecies name 'erronea' reflects its historical taxonomic confusion.
Euphydryas anicia capella
Euphydryas anicia capella is a subspecies of checkerspot butterfly in the family Nymphalidae, originally described by W. Barnes in 1897. It is currently recognized as a synonym of Occidryas anicia capella in some taxonomic databases, reflecting ongoing taxonomic revision within the Euphydryas complex. The species belongs to a group of fritillary butterflies known for their distinctive orange and black checkered wing patterns and association with specific host plants.
Euphydryas chalcedona wallacensis
Euphydryas chalcedona wallacensis is a subspecies of the Variable Checkerspot butterfly, endemic to the Sierra Nevada mountains of California. It represents a geographically isolated population of Euphydryas chalcedona that has adapted to high-elevation habitats. The subspecies is of conservation concern due to its restricted range and vulnerability to climate change impacts on montane ecosystems.
Euphyes
grass skippers
Euphyes is a genus of grass skippers (Hesperiidae: Hesperiinae) comprising approximately 22 species distributed across North America, the Caribbean, and parts of Central America. Species are typically associated with wetland and grassland habitats, with larvae feeding on sedges (Cyperaceae) and other monocots. The genus includes several regional endemics and habitat specialists, some of conservation concern.
Euphyes arpa
Palmetto Skipper
Euphyes arpa, commonly known as the Palmetto Skipper, is a butterfly in the family Hesperiidae. The species is endemic to the southeastern United States, with its range centered on Florida and extending into adjacent states. It is closely associated with saw palmetto (Serenoa repens) habitats, where larvae feed exclusively on fronds and adults nectar at flowers. Despite having an abundant food source, the species is declining for reasons that remain unclear, and it has been assessed as vulnerable by NatureServe.
Euphyes bimacula
Two-spotted Skipper
Euphyes bimacula, the two-spotted skipper, is a small butterfly in the family Hesperiidae found across eastern and central North America. It is distinguished by dark brown upperside wings and pale tawny orange undersides, with a wingspan of 25–30 mm. The species is listed as endangered in Connecticut. Larvae feed specifically on Carex trichocarpa, while adults nectar on several flowering plants including pickerelweed and common milkweed.
Euphyes dukesi
Dukes' skipper
Euphyes dukesi, known as Dukes' skipper, is a small wetland-associated skipper butterfly endemic to eastern North America. The species exhibits a fragmented distribution across three geographically isolated populations: the Atlantic coastal plain, the lower Mississippi Valley, and the Great Lakes region. It is strictly associated with shaded wetland habitats where sedges serve as larval host plants. The species was first described in 1923 from Alabama and named for collector W. C. Dukes. Two subspecies are recognized: the nominate form and the Florida-endemic E. d. calhouni, which occupies swamp habitats with distinct morphological differences.
Euproserpinus euterpe
Kern primrose sphinx moth, euterpe sphinx moth
Euproserpinus euterpe is a small, day-flying sphinx moth endemic to California and federally listed as threatened. Adults are active from mid-January to early April, with peak activity in February and March. The species has a highly restricted, disjunct distribution limited to two known locations in Kern and San Luis Obispo counties. Larvae are specialized feeders on evening primrose (Camissonia species), while adults nectar on diverse regional wildflowers. Population abundance fluctuates dramatically with climatic conditions, particularly rainfall.
federally-threatenedendemicdiurnalspecialist-herbivoreglacial-relictCalifornia-endemicevening-primrose-feedersandy-soil-pupationpopulation-fluctuationconservation-concerninsect-collecting-threathabitat-specialistdisjunct-distributionlate-winter-emergencemorning-eclosionagricultural-disturbance-toleranceBureau-of-Land-Managementrecovery-plan-speciespresumed-extinct-rediscoveryclimate-sensitive-population-dynamicsEuxoa pleuritica
fawn brown dart
Euxoa pleuritica is a noctuid moth known as the fawn brown dart, found across northern North America from southern Canada through the northern United States. The species is listed as a species of special concern in Connecticut. Adults are active during summer months, with one generation per year. Larvae have been documented feeding on Salsola kali.
Euxoa violaris
Violet Dart, violet dart moth
Euxoa violaris, the violet dart moth, is a species of noctuid moth native to North America. Described in 1868 by Grote and Robinson, it is listed as a species of special concern in Connecticut. As a member of the genus Euxoa, its larvae likely share characteristics with other cutworms in the genus, though species-specific biology remains poorly documented.
Exyra fax
Pitcher Plant Moth, Epauletted Pitcher Plant Moth
Exyra fax, commonly known as the Pitcher Plant Moth, is a small noctuid moth specialized on pitcher plants. It occurs in eastern North America from Manitoba through the Great Lakes region to the Atlantic Coastal Plain, with a range extending from Nova Scotia south to Georgia. The species is in decline due to habitat disruption and is listed as threatened in Connecticut. Adults are active during summer months, and larvae are obligate feeders on Sarracenia purpurea.
Fagitana littera
Marsh Fern Moth
Fagitana littera, commonly known as the marsh fern moth, is a noctuid moth described by Achille Guenée in 1852. The species is notable for its highly specialized larval ecology, with Thelypteris palustris (marsh fern) reported as its only known host plant. It is listed as a species of special concern in Connecticut, reflecting potential vulnerability due to habitat specificity. The species occurs in North America, though detailed distribution and life history information remain limited in published sources.
Fitchiella robertsonii
ball-nosed planthopper
Fitchiella robertsonii is a rare, diminutive planthopper historically known from fewer than 20 collection sites across North America. The species was considered potentially extinct until its rediscovery in Iowa tallgrass prairie in 2008, with subsequent 12-year research yielding 219 specimens—representing 90% of all known collections. Adults measure less than 5 mm but can leap 35 inches in a single jump, roughly 250 times their body length. The species exhibits both brachypterous (short-winged, flightless) and macropterous (long-winged) forms.
Frenesia
Dot Wing Winter Sedges
Frenesia is a genus of northern caddisflies in the family Limnephilidae, commonly known as Dot Wing Winter Sedges. The genus contains at least two described species: Frenesia difficilis and Frenesia missa. Members of this genus are associated with cool-season activity patterns, as suggested by their common name. Frenesia missa is considered a rare species with documented vulnerability to anthropogenic stressors.
Glena cognataria
Blueberry Gray, blueberry gray moth
Glena cognataria, commonly known as the blueberry gray moth, is a small geometrid moth native to eastern North America. Adults have forewings measuring 13–15 mm. The species is associated with bogs and pine barrens habitats, with larvae feeding primarily on blueberry and various hardwood species. It is listed as a species of special concern in Connecticut, where it is believed extirpated.
Gomphurus ozarkensis
Ozark Clubtail
Gomphurus ozarkensis is a clubtail dragonfly endemic to the south-central United States. Described in 1975, it occupies a restricted four-state range spanning southeastern Kansas, eastern Oklahoma, western and northern Arkansas, and southern Missouri. The species exhibits geographic variation across three distinct subpopulations separated by watershed boundaries. Its limited distribution has prompted conservation concern.
Gracillariinae
Gracillariinae is a subfamily of leaf-mining moths within the family Gracillariidae, first described by Henry Tibbats Stainton in 1854. The subfamily contains diverse genera including Caloptilia, Gracillaria, and Sabulopteryx. Larvae are predominantly leaf miners, with most species exhibiting a characteristic life cycle involving an initial sap-feeding instar with modified mouthparts, though some species have been shown to deviate from this pattern. The subfamily has been subject to significant taxonomic revision, with phylogenetic studies in 2017 reorganizing generic placements among related subfamilies.
Grylloblatta campodeiformis
Northern Rock Crawler
Grylloblatta campodeiformis, the northern rock crawler, is a wingless, cold-adapted insect endemic to western North America. It was the first grylloblatid species described scientifically (Walker, 1914) and serves as the type species for both its genus and family. The species occupies a broader range of habitats than previously assumed, from high-altitude glacial margins to subalpine forests and even low-elevation dry zones. Four subspecies are currently recognized, distributed across the Canadian Rockies and adjacent mountain ranges in British Columbia, Alberta, Montana, and Washington.
Gryllotalpa major
prairie mole cricket
Gryllotalpa major, the prairie mole cricket, is the largest cricket species in North America, endemic to the tallgrass prairie ecosystems of the south-central United States. Males exhibit a classical lekking mating system, constructing specialized acoustic burrows that amplify their calling songs to attract flying females from distances up to 400 meters. The species is threatened by habitat loss due to prairie conversion, with current populations restricted to fragmented sites in Oklahoma, Kansas, Missouri, Nebraska, and Arkansas. Research has documented unique acoustic behaviors, including harmonic chirps rather than trills, and vibrational communication between neighboring males through the soil.
Hemaris gracilis
slender clearwing, graceful clearwing
Hemaris gracilis, commonly known as the slender clearwing or graceful clearwing, is a moth in the family Sphingidae. It is distinguished from related clearwing moths by red-brown bands on the thorax and a red abdomen. The species is considered the rarest of the three North American Hemaris species and is listed as threatened in Connecticut and of Special Concern in Massachusetts. Adults are active from March through August, with likely two generations per year in its range.
Hexurella
dwarf funnel web spiders
Hexurella is a genus of dwarf funnel web spiders (Mygalomorphae, Hexurellidae) comprising some of the smallest mygalomorph spiders in the world. Adults measure 2.5–5 mm in body size. The genus represents a phylogenetically ancient, relictual lineage that diverged from other atypoids approximately 300 million years ago. As of 2026, the genus contains eight species, with four described in a 2023 taxonomic revision. Several species have highly restricted geographic ranges and may warrant conservation attention.
Hybomitra lurida
Broad-headed Horse Fly
Hybomitra lurida is a large horse-fly species in the family Tabanidae, measuring 12–15 millimetres in length. It is distributed across central and northern Europe, Asia, and North America including Canada, Alaska, and portions of the contiguous United States. Adults are active during summer months and are frequently associated with cattle in open landscapes.
Hylaeus
Masked Bees, Yellow-faced Bees
Hylaeus is a large, diverse genus of solitary bees in the family Colletidae, commonly known as masked bees or yellow-faced bees. The genus contains over 500 species with cosmopolitan distribution, reaching peak diversity in subtropical Australia and the Hawaiian Islands. These bees are distinguished by their nearly hairless, wasp-like appearance and unique method of transporting nectar and pollen internally in a crop rather than externally on body hairs. Many species nest in pre-existing cavities such as hollow stems, beetle borings in wood, or abandoned galls.
Hypochilus coylei
lampshade weaver
Hypochilus coylei is a lampshade spider described by Platnick in 1987 from the southern Appalachian Mountains of western North Carolina. It belongs to a relictual genus of microhabitat specialists with disjunct distributions across three North American montane regions. The species is sister to H. thorelli and exhibits extreme genetic divergence coupled with morphological stasis, characteristic of short-range endemic taxa with limited dispersal ability.
Hypochilus petrunkevitchi
lampshade spider
Hypochilus petrunkevitchi is a lampshade spider endemic to the southern Sierra Nevada of California. It exhibits extreme intraspecific genetic divergence, with nuclear and mitochondrial lineages corresponding directly to drainage basins. Populations show >15% CO1 divergence between river basins despite striking male morphological stasis. The species is a textbook example of a short-range endemic with naturally limited dispersal ability.
Hypochilus pococki
Pocock's lampshade-web spider
Hypochilus pococki is a relictual lampshade spider endemic to the southern Appalachian Mountains. It belongs to a paleoendemic genus distributed disjunctly across three montane regions in North America. The species exhibits extreme genetic divergence over small geographic distances, with five identified mitochondrial haplogroups, yet shows striking morphological stasis in male reproductive structures. As a microhabitat specialist, it has extremely low dispersal ability, leading to pronounced population genetic structuring.
Larinus carlinae
Canada thistle bud weevil, thistle bud weevil, Canada thistle stem weevil
A small weevil native to Europe and western Asia introduced to North America as a biological control agent for invasive thistles. Adults emerge in spring and feed on developing thistle buds with their elongated snouts. Females drill into flower buds to deposit eggs; larvae hatch and consume reproductive tissues, destroying seeds and preventing plant reproduction. Populations can reduce target thistle species by 90% or more within a decade of establishment. The species has been observed feeding on native North American thistles, raising conservation concerns for endemic species.
Libellula jesseana
Purple Skimmer
Libellula jesseana, the purple skimmer, is a threatened dragonfly endemic to Florida, United States. Adults measure approximately 5 centimeters in length. The species is restricted to infertile, clear, sandy-bottomed lakes with specific shoreline vegetation, and is critically imperiled due to habitat degradation from human development.
Limnocoris moapensis
moapa warm springs naucorid, Warm Springs Naucorid
Limnocoris moapensis is a rare species of creeping water bug in the family Naucoridae. It is endemic to warm spring habitats in the Moapa Valley of Nevada, USA. The species is known from very few observations and is considered vulnerable due to its restricted range and dependence on thermal spring ecosystems. It belongs to the subfamily Limnocorinae, a group specialized for life in aquatic environments.