Try for Free
tab list
Picture Insect
English
arrow
English
繁體中文
日本語
Español
Français
Deutsch
Pусский
Português
Italiano
한국어
Nederlands
العربية
Home Application Download FAQ
English
English
繁體中文
日本語
Español
Français
Deutsch
Pусский
Português
Italiano
한국어
Nederlands
العربية
Icon about
About
Icon about
General Info
Icon about
Search Tips
Icon about
Harmful or Not
Icon about
Common FAQs
Icon about
Similar Insects
Icon about
Popular Insects
Eastern Dobsonfly

Eastern Dobsonfly

Corydalus cornutus

A species of Dobsonflies, Also known as Dobson, Grampus, Hellgrammite Fly, Toe biter

The eastern Dobsonfly (Corydalus cornutus) is best known for its large, sickle-like mandibles. They are also prized as bait for fish like smallmouth bass (Micropterus dolomieu). They are considered beneficial insects, so their usage as bait has been restricted in many states.

General Info About Eastern Dobsonfly
Instantly identify insects with a snap
Snap a photo for instant insect ID and risk assessment, gaining quick insights on bite assessment, toxicity, pest control, behavior, habitat, and safe interaction tips, etc.
Download the App for Free
Rectangle
Attributes of Eastern Dobsonfly
Colors
Brown
Habitat
river; stream; riparian
Adult Food Sources
Adult probably eats nothing.
Larva Food Source
Small invertebrates, tadpoles, larval fish, aquatic insects, worms
Biting/stinging
Not reported
Allergy-causing
Not reported
Defensive attack
The Eastern Dobsonfly has special defensive behaviors that can trigger an allergic reaction. If there are serious reactions, seek IMMEDIATE medical attention.
Pest-Eating Predatory
Not reported
Phytophagous
Not reported
Predatory
The Eastern Dobsonfly typically preys on other arthropods and does not directly affect plants.
Biting animal or pet
Yes
Mouthparts Type
Chewing mouthparts
qrcode
Img download isoImg download android
Rectangle
Species Status of Eastern Dobsonfly
It is found in most of eastern North America.
Rectangle
Distribution Area of Eastern Dobsonfly
Eastern North America
Rectangle
Appearance of Eastern Dobsonfly
The eggs are grey and cylindrical. The larvae are light brown with a covering of tiny dark brown microspines. The pupae are orange in colour with dark patches on the upper side of the abdomen and are covered with minute bristles. The adult dobsonfly is a large insect up to 14 cm long with a wingspan of up to 13 cm. The female has short powerful mandibles of a similar size to those of the larva while the mandibles of the male are sickle-shaped and up to 4 cm long, half as long as the body.
ImageImageImageImageImage

How to Identify Eastern Dobsonfly?

Rectangle
Life Cycle of Eastern Dobsonfly
Egg The eggs of eastern Dobsonfly are laid in clusters and are typically oval-shaped. This stage is brief, with eggs often attached to a substrate near water, as eastern Dobsonfly is aquatic in its early stages.
Larva Upon hatching, the larvae of eastern Dobsonfly are elongated with prominent mandibles for feeding. They are typically aquatic predators, with a mottled brown color for camouflage. Their size increases with each molt.
Pupal The eastern Dobsonfly enters the pupal stage in a cocoon-like structure in a terrestrial habitat. During this stage, massive reorganization occurs as eastern Dobsonfly transforms, developing wings and adult structures in a static state.
Adult Emerging from the pupa, the adult eastern Dobsonfly’s development is marked by the presence of wings and functional reproductive organs. The body is fully formed and hardened, and the adult is mobile, focusing on reproduction.
Rectangle
Adult Size of Eastern Dobsonfly
5 cm
Rectangle
Predators of Eastern Dobsonfly Larvae
Anura (frogs and toads), aves (birds), arachnida (spiders), mantodea (mantises), odonata (dragonflies, in nymph form)
Rectangle
Predators of Adult Eastern Dobsonfly
Aves (birds), chiroptera (bats), arachnida (spiders)
Rectangle
Scientific Classification of Eastern Dobsonfly
Tips for Finding Eastern Dobsonfly
Your ultimate guide to understanding insects
Unlock the secrets of insect life cycles, habitats, behaviors and observation tips!!
Download the App for Free
Rectangle
How Can You Attract Eastern Dobsonfly
Adult eastern Dobsonfly are attracted to light sources at night, making them easier to find when using light traps. Larvae, also known as hellgrammites, are not attracted to food baits but are found near aquatic environments.
Rectangle
Habitat Preferences of Eastern Dobsonfly Through Different Life Stages
In their aquatic larval stage, eastern Dobsonfly are primarily found under rocks in streams and riverbeds, where the flowing water is rich in oxygen. These habitats provide ample prey for their carnivorous diet. The pupal stage of eastern Dobsonfly occurs in the soil or under debris near water bodies where they have greater protection during this vulnerable period. Adult eastern Dobsonfly, often observed near the same streams and rivers, are typically found resting on nearby vegetation or flying in the vicinity during mating season. Consequently, to observe the distinct stages of eastern Dobsonfly, one must explore the aquatic environment for larvae, sift through the riparian soil or debris for pupae, and scan surrounding terrestrial habitats for adults.
Rectangle
When is the Best Time to Observe Eastern Dobsonfly
Adult eastern Dobsonfly are typically active at night, especially soon after dusk, making this the optimal time to observe or capture them. Larvae are available year-round in their aquatic habitats but are easier to find during the daylight hours when thoroughly searching under rocks and debris in streams.
Rectangle
What is the Best Weather to Observe Eastern Dobsonfly
Mild to warm weather without heavy winds or rain is most suitable for finding adult eastern Dobsonfly. Larvae require consistent aquatic environments and therefore can be searched for regardless of weather, as long as water bodies are not frozen or in flood.
Rectangle
How and Where Can You Find Eastern Dobsonfly at Different Life Stages
Egg Eastern Dobsonfly eggs are laid on vegetation near water sources. Search for clusters of eggs on the undersides of leaves or stems hanging close to the water.
Larva Eastern Dobsonfly larvae, known as hellgrammites, reside in streams and rivers. Look for them under rocks, leaves, and debris within the water. Gently turn over stones and examine the undersides for these aquatic creatures.
Pupal Eastern Dobsonfly pupae can be found in the soil near stream banks. Identify areas with loose, damp soil and carefully excavate to discover the pupating specimens.
Adult Adult eastern Dobsonfly are nocturnal and can be found near bodies of water or attracted to lights at night. Utilize a light source after dusk to draw them in or search for resting individuals on vegetation near water during early morning.
Are Eastern Dobsonfly harmful?
Your Complete Pest Control Guide
Discover effective tips for preventing and eliminating pest infestations to keep bugs away from your home.
Download the App for Free
Common Questions People Also Ask
Get Quick Insect Answers with a Snap
Snap a photo for instant insect ID and answers on bites, toxicity, pest control, behavior, habitat, and safety tips!
Download the App for Free
More Insects that are Similar to Eastern Dobsonfly
Toe biter
Toe biter

The larval form of Archichauliodes diversus is commonly known by the name toe biter, which refers to its pincer-like powerful jaws. The larvae and adults have totally different lifestyles. The larvae live in streams and feed on aquatic invertebrates while adults can only survive on lands and would die soon after spawning.

Read More
Arrow
Protohermes grandis
Protohermes grandis

Protohermes grandis is a large, colorful species of dobsonfly occurring in China, Japan, Korea, and Taiwan. “The TDF for P.grandis larvae suggests that their low TPs in nature were caused by incorporation of vascular plant-derived amino acids (with a different N-15 profile from that of algae) and not by an unusually low TDF or by the effects of the satiation/starvation on amino acid metabolism.

Read More
Arrow
Dark fishfly
Dark fishfly

Nigronia serricornis is an insect from the family Corydalidae, which belongs to the order of large-winged species (Megaloptera). The species is found in the mid-south of Canada and the east of the United States.

Read More
Arrow
A hellgrammite
A hellgrammite

Neohermes concolor is an insect from the family Corydalidae, which belongs to the order large-winged (Megaloptera). The species is found in the eastern United States.

Read More
Arrow
Neohermes filicornis
Neohermes filicornis

Neohermes filicornis is a species of fishfly in the family Corydalidae. It is found in North America.

Read More
Arrow
Summer fishfly
Summer fishfly

The summer fishfly (Chauliodes pectinicornis) looks strange, but is not dangerous. Unlike many other insects, its naiads have gills and live in water for 2 or 3 years before emerging in the hottest days of summer. The adult is usually observed by the water in the summer.

Read More
Arrow
Spring Fishfly
Spring Fishfly

The spring Fishfly (Chauliodes rastricornis) spends most of its time near calm bodies of water. Living a simple life, their main oddity is laying their eggs in a v-shaped pattern so that they may easily enter the water. They spend their time for three weeks in the water, usually around water-soaked logs. Adults usually do not feed, but they may be attracted to moth bait.

Read More
Arrow
Other Popular Insects
Western honey bee
Western honey bee

Western honey bee(Apis mellifera) is the most common species of honeybee in the world. Among the first domesticated insects, its cultural and economic impact on humanity has been vast and far-reaching, providing honey, wax and its services as a pollinator. Western honey bee faces challenges worldwide, such as colony collapse disorder, and populations are thought to be decreasing.

Read More
Arrow
Monarch butterfly
Monarch butterfly

The monarch butterfly (Danaus plexippus) is the most recognizable butterfly in North America. It is best known for its appearance, but should be better known for the fact that it has a 3000-mile migration that takes the butterfly 4 generations to complete. Their diet is also a natural deterrent for predators, as they eat milkweed, a poison that induces vomiting.

Read More
Arrow
Japanese rhinoceros beetle
Japanese rhinoceros beetle

The japanese rhinoceros beetle (Trypoxylus dichotomus) is a massive beetle about the size of the palm of a hand. It's distinguished by its long Y-shaped horn, which it uses to fight other males with. It's a nocturnal bug that feeds on sap and sweet fruits. This species is sometimes kept as a pet due to its unique appearance and simple care requirements.

Read More
Arrow
Silkworm
Silkworm

The silken threads produced by silkworm during its larval stage have been highly coveted for millennia, manifesting as a luxurious fabric in human society. Remarkably, this creature has a singular diet, feeding exclusively on the leaves of its primary host plant from which it extracts the necessary nutrients to facilitate its transition into a non-feeding, winged adult.

Read More
Arrow
Menelaus blue morpho
Menelaus blue morpho

Menelaus blue morpho (Morpho menelaus) is a gorgeous butterfly with large, royal blue wings. Linnaeus named the genus Morpho the Aphrodite-Ancient Greek goddess of love and beauty for its extreme beauty. It is native to tropical rainforests. Though many butterfly gardens now cultivate them in captivity, there are still many people who never get a chance to see them.

Read More
Arrow
Atlas moth
Atlas moth

While the atlas moth (Attacus atlas) can't tell you where to find your country on the map, it does earn its name through other means. It is one of the largest moths in the world, with a wingspan that is far larger than its body, creating an abnormal comparison. In India, their silk is gathered in a non-commercial capacity and is considered to be more durable than the domestic silkworm.

Read More
Arrow
Flying peacock spider
Flying peacock spider

Both sexes reach about 5 mm in body length. Females and immatures of both sexes are brown but have color patterns by which they can be distinguished from related species. Also, the males dance to attract females.

Read More
Arrow
Multicolored asian ladybeetle
Multicolored asian ladybeetle

Often confused for the ladybug, multicolored asian ladybeetle (Harmonia axyridis) is a separate species that, unlike the ladybug, is a household pest. It is considered particularly annoying for its habit of returning to places from which it is removed. One of the most variable species in the world, there are many different colors and patterns multicolored asian ladybeetle may display, making identification potentially difficult.

Read More
Arrow