Overview

Distribution

Geographic Range

Corydalus_cornutus is found in or near the rivers and streams of eastern North America.

Biogeographic Regions: nearctic (Native )

  • McCafferty, W. 1983. Aquatic Entomology: The Fishermen's and Ecologists' Illustrated Guide to Insects and Their Relatives. Boston, Massachusetts, USA: Jones and Bartlett Publishers, Inc..
  • Evans, E., H. Neunzig. 1996. Megaloptera and Aquatic Neuroptera. Pp. 298-308 in R Merritt, K Cummins, eds. An Introduction to the Aquatic Insects of North America. Dubuque, Iowa, USA: Kendall/Hunt Publishing Company.
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Geographic Range

Corydalus cornutus is found in or near the rivers and streams of eastern North America.

Biogeographic Regions: nearctic (Native )

  • McCafferty, W. 1983. Aquatic Entomology: The Fishermen's and Ecologists' Illustrated Guide to Insects and Their Relatives. Boston, Massachusetts, USA: Jones and Bartlett Publishers, Inc..
  • Evans, E., H. Neunzig. 1996. Megaloptera and Aquatic Neuroptera. Pp. 298-308 in R Merritt, K Cummins, eds. An Introduction to the Aquatic Insects of North America. Dubuque, Iowa, USA: Kendall/Hunt Publishing Company.
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occurs (regularly, as a native taxon) in multiple nations

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National Distribution

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

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Global Range: (200,000-2,500,000 square km (about 80,000-1,000,000 square miles)) It can be found throughout the southwestern portion of the United States west of the Rocky Mountains (Contreras-Ramos, 1998). Contreras-Ramos (2007) lists Guatemala, Mexico, and the United States.

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occurs (regularly, as a native taxon) in multiple nations

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National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

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Global Range: (200,000 to >2,500,000 square km (about 80,000 to >1,000,000 square miles)) It is widespread from Texas and New Mexico, north and east throughout the Midwest and eastern United States and into parts of southeastern Canada (Rasmussen and Pescador, 2002). It is generally widespread east of the Rocky Mountains. Although collected in Texas, close to the Mexican border, it has never been collected in Mexico (Contreras-Ramos, 2007).

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Physical Description

Morphology

Physical Description

Dobsonfly larvae, sometimes called hellgrammites, are flattened and elongate, dark brown in color, with a segmented body. They have a wide head with strong biting mouthparts, 3 pairs of thoracic legs, and a eight pairs lateral filaments, one to a segment, down each side of the body, each with a gill tuft at the base of the filament. They are distinguished from stonefly (Plecoptera) larvae by the pair of prolegs at the hind end of the abdomen, each of which has two terminal hooks. Fully-grown larvae may be as long as 90 mm.

Pupae and adults have large mandibles, also a wide head, and an elongate abdomen. Adults are tan or light brown, with darker mottling, and are up to 75 mm long. They have two pairs of large, strongly-veined wings. The forewings are translucent grey-brown, with darker markings, especially on the veins. At rest they are held folded over the back, in a roof-like arrangment. The mandibles of adult males are extremely long (up to half the body length, and horn-like.

Range length: 90 (high) mm.

Sexual Dimorphism: ornamentation

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Physical Description

Dobsonfly larvae, sometimes called hellgrammites, are flattened and elongate, dark brown in color, with a segmented body. They have a wide head with strong biting mouthparts, 3 pairs of thoracic legs, and a eight pairs lateral filaments, one to a segment, down each side of the body, each with a gill tuft at the base of the filament. They are distinguished from stonefly (Plecoptera) larvae by the pair of prolegs at the hind end of the abdomen, each of which has two terminal hooks. Fully-grown larvae may be as long as 90 mm.

Pupae and adults have large mandibles, also a wide head, and an elongate abdomen. Adults are tan or light brown, with darker mottling, and are up to 75 mm long. They have two pairs of large, strongly-veined wings. The forewings are translucent grey-brown, with darker markings, especially on the veins. At rest they are held folded over the back, in a roof-like arrangment. The mandibles of adult males are extremely long (up to half the body length, and horn-like.

Range length: 90 (high) mm.

Sexual Dimorphism: ornamentation

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Ecology

Habitat

The eggs of Corydalus_cornutus are laid tree branches, rocks, or other structures that are over or immediately adjacent to moving water. The larvae live on the bottoms of fast-moving (well-oxygenated) streams and rivers, climbing over gravel, cobbles, sand, soft sediments, and organic debris. They are not usually found on living aquatic plants. Dobsonflies pupate on land, usually hidden in muddy soil or decaying wood near a streambank. Adults tend to stay near to streams, mating occurs on the ground or on vegetation.

Habitat Regions: temperate ; freshwater

Aquatic Biomes: benthic ; rivers and streams

Other Habitat Features: riparian

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The eggs of Corydalus cornutus are laid tree branches, rocks, or other structures that are over or immediately adjacent to moving water. The larvae live on the bottoms of fast-moving (well-oxygenated) streams and rivers, climbing over gravel, cobbles, sand, soft sediments, and organic debris. They are not usually found on living aquatic plants. Dobsonflies pupate on land, usually hidden in muddy soil or decaying wood near a streambank. Adults tend to stay near to streams, mating occurs on the ground or on vegetation.

Habitat Regions: temperate ; freshwater

Aquatic Biomes: benthic ; rivers and streams

Other Habitat Features: riparian

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Trophic Strategy

Food Habits

Hellgrammites, the larvae of Corydalus_cornutus and other Corydalidae, are active predators that feed on a wide variety of small stream invertebrates, including insects and other arthropods, small worms, and small molluscs. They are generalists, whose diet choices probably reflect relative abundance of different prey types rather than specialization. They are known to particularly feed on blackfly larvae (Simuliidae) and the larvae of net-spinning caddisflies (several familiies in the Trichoptera) and mayflies (Ephemeroptera).

Adults are not believed to take solid food. Females are reported to feed on nectar from flowers, males are not believed to eat at all.

Animal Foods: insects; mollusks; aquatic or marine worms; aquatic crustaceans

Plant Foods: nectar

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Food Habits

Hellgrammites, the larvae of Corydalus cornutus and other corydalids, are active predators that feed on a wide variety of small stream invertebrates, including insects and other arthropods, small worms, and small molluscs. They are generalists, whose diet choices probably reflect relative abundance of different prey types rather than specialization. They are known to particularly feed on blackfly larvae (Simuliidae) and the larvae of net-spinning caddisflies (several familiies in the Trichoptera) and mayflies (Ephemeroptera).

Adults are not believed to take solid food. Females are reported to feed on nectar from flowers, males are not believed to eat at all.

Animal Foods: insects; mollusks; aquatic or marine worms; aquatic crustaceans

Plant Foods: nectar

Primary Diet: carnivore (Insectivore )

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Associations

Ecosystem Roles

This species is a mid-level predator, feeding on smaller animals, but also fed upon by larger predators. In small stream where fish are small or rare, large hellgrammites may be some of the largest predators in the water.

Some very small parasitoid wasp species in the genus Trichogramma are known to lay their eggs in the eggs of Corydalus_cornutus. The wasp larvae consume the host egg, and emerge as adult wasps.

Commensal/Parasitic Species:

  • parasitoid wasp species in Trichogramma 

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Predation

Corydalus_cornutus avoids predators by limiting its activity in daylight, by hiding, and by biting in self-defense if necessary. Adults and larvae are cryptically colored. We have no information on specific predator species. Stream fish eat them, and probably some crayfish. Birds and bats are probably natural enemies of adult dobsonflies.

Anti-predator Adaptations: cryptic

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Ecosystem Roles

This species is a mid-level predator, feeding on smaller animals, but also fed upon by larger predators. In small stream where fish are small or rare, large hellgrammites may be some of the largest predators in the water.

Some very small parasitoid wasp species in the genus Trichogramma are known to lay their eggs in the eggs of Corydalus cornutus. The wasp larvae consume the host egg, and emerge as adult wasps.

Commensal/Parasitic Species:

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Predation

Corydalus cornutus avoids predators by limiting its activity in daylight, by hiding, and by biting in self-defense if necessary. Adults and larvae are cryptically colored. We have no information on specific predator species. Stream fish eat them, and probably some crayfish. Birds and bats are probably natural enemies of adult dobsonflies.

Anti-predator Adaptations: cryptic

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Life History and Behavior

Behavior

Communication and Perception

Hellgrammites, the larval stage of Corydalus_cornutus, probably rely mainly on touch and chemical sensing to locate prey. They do have eyes though and can at least detect motion and shadow.

Adult male dobsonflies have scent glands on their abdomen that apparently play some role in mating. They also lay their mandibles over females when courting them, so touch is relevant too.

Communication Channels: tactile ; chemical

Other Communication Modes: pheromones

Perception Channels: visual ; tactile ; chemical

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Communication and Perception

Hellgrammites, the larval stage of Corydalus cornutus, probably rely mainly on touch and chemical sensing to locate prey. They do have eyes though and can at least detect motion and shadow.

Adult male dobsonflies have scent glands on their abdomen that apparently play some role in mating. They also lay their mandibles over females when courting them, so touch is relevant too.

Communication Channels: tactile ; chemical

Other Communication Modes: pheromones

Perception Channels: visual ; tactile ; chemical

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Life Cycle

Development

This is a holometabolous species, with four life stages: egg, larva, pupa, and adult. The eggs, pupae, and adults breath air and live on land. The larvae are aquatic, and take their oxygen from the water. Nearly all feeding and growth occurs in the larval stage, which may molt as many as 10 times as it grows. Larval development is strongly affected by temperature: larvae in colder climates and colder streams take longer to grow (sometimes spending two winters in the larval stage before) and may be larger when they transform.

Development - Life Cycle: metamorphosis

  • Anderson, N. 2003. Megaloptera (Alderflies, Dobsonflies). Pp. 700-703 in V Resh, R Cardé, eds. Encyclopedia of Insects. New York City, New York, USA: Academic Press.
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Development

This is a holometabolous species, with four life stages: egg, larva, pupa, and adult. The eggs, pupae, and adults breath air and live on land. The larvae are aquatic, and take their oxygen from the water. Nearly all feeding and growth occurs in the larval stage, which may molt as many as 10 times as it grows. Larval development is strongly affected by temperature: larvae in colder climates and colder streams take longer to grow (sometimes spending two winters in the larval stage before) and may be larger when they transform.

Development - Life Cycle: metamorphosis

  • Anderson, N. 2003. Megaloptera (Alderflies, Dobsonflies). Pp. 700-703 in V Resh, R Cardé, eds. Encyclopedia of Insects. New York City, New York, USA: Academic Press.
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Life Expectancy

Lifespan/Longevity

Corydalus_cornutus takes one to three years to complete its life-cycle.

Range lifespan

Status: wild:
3 (high) years.

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Lifespan/Longevity

Corydalus cornutus takes one to three years to complete its life-cycle.

Range lifespan

Status: wild:
3 (high) years.

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Reproduction

Adults mate within days of emergence, in late spring or summer. Mating occurs near streams, on the ground or on vegetation. Males may use their elongate mandibles in contests with other males. They also use them in courtship and mating behavior with females.

Female dobsonflies lay eggs very soon after mating. They produce up to three masses of eggs, usually on the undersides of leaves, branches, or other structures over-hanging a stream. Each mass may contain as many as 1000 eggs, laid in 1-5 layers and covered with a white protective material. Eggs incubate for 2-3 weeks before the new larvae hatch and drop or crawl to water.

The life-cycle of this species is strongly affected by temperature -- in the southern part of the range they can complete a generation in less than a year, but further north it may take 2-3 years. Adults only live for a few days -- females die after laying their eggs.

Breeding season: Dobsonflies mate and lay eggs in spring and summer.

Range eggs per season: 3000 (high) .

Range age at sexual or reproductive maturity (female): 1 to 3 years.

Range age at sexual or reproductive maturity (male): 1 to 3 years.

Key Reproductive Features: semelparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous

Only parental investment is in choosing egg-laying site, and provisioning eggs.

Parental Investment: pre-fertilization (Provisioning)

  • McCafferty, W. 1983. Aquatic Entomology: The Fishermen's and Ecologists' Illustrated Guide to Insects and Their Relatives. Boston, Massachusetts, USA: Jones and Bartlett Publishers, Inc..
  • Anderson, N. 2003. Megaloptera (Alderflies, Dobsonflies). Pp. 700-703 in V Resh, R Cardé, eds. Encyclopedia of Insects. New York City, New York, USA: Academic Press.
  • Evans, E., H. Neunzig. 1996. Megaloptera and Aquatic Neuroptera. Pp. 298-308 in R Merritt, K Cummins, eds. An Introduction to the Aquatic Insects of North America. Dubuque, Iowa, USA: Kendall/Hunt Publishing Company.
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Adults mate within days of emergence, in late spring or summer. Mating occurs near streams, on the ground or on vegetation. Males may use their elongate mandibles in contests with other males. They also use them in courtship and mating behavior with females.

Female dobsonflies lay eggs very soon after mating. They produce up to three masses of eggs, usually on the undersides of leaves, branches, or other structures over-hanging a stream. Each mass may contain as many as 1000 eggs, laid in 1-5 layers and covered with a white protective material. Eggs incubate for 2-3 weeks before the new larvae hatch and drop or crawl to water.

The life-cycle of this species is strongly affected by temperature -- in the southern part of the range they can complete a generation in less than a year, but further north it may take 2-3 years. Adults only live for a few days -- females die after laying their eggs.

Breeding season: Dobsonflies mate and lay eggs in spring and summer.

Range eggs per season: 3000 (high) .

Range age at sexual or reproductive maturity (female): 1 to 3 years.

Range age at sexual or reproductive maturity (male): 1 to 3 years.

Key Reproductive Features: semelparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous

Only parental investment is in choosing egg-laying site, and provisioning eggs.

Parental Investment: pre-fertilization (Provisioning)

  • McCafferty, W. 1983. Aquatic Entomology: The Fishermen's and Ecologists' Illustrated Guide to Insects and Their Relatives. Boston, Massachusetts, USA: Jones and Bartlett Publishers, Inc..
  • Anderson, N. 2003. Megaloptera (Alderflies, Dobsonflies). Pp. 700-703 in V Resh, R Cardé, eds. Encyclopedia of Insects. New York City, New York, USA: Academic Press.
  • Evans, E., H. Neunzig. 1996. Megaloptera and Aquatic Neuroptera. Pp. 298-308 in R Merritt, K Cummins, eds. An Introduction to the Aquatic Insects of North America. Dubuque, Iowa, USA: Kendall/Hunt Publishing Company.
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Molecular Biology and Genetics

Molecular Biology

Barcode data: Corydalus cornutus

The following is a representative barcode sequence, the centroid of all available sequences for this species.


There are 3 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.

CGAAAATGATTATTTTCTACGAATCACAAAGATATTGGAACTTTATACTTTCTTTTTGGAACTTGAGCCGGCATAGTCGGAACTTCTCTT---AGTCTTTTAATTCGAGCTGAATTAGGTCAACCAGGATCTTTAATTGGAGAT---GACCAAATTTATAATGTTATTGTAACTGCTCATGCTTTTGTAATAATTTTTTTCATGGTTATACCTATTATAATCGGAGGATTTGGAAATTGACTTGTTCCATTAATA---CTGGGGGCCCCAGATATAGCCTTTCCACGAATAAATAATATAAGTTTTTGACTTCTTCCTCCCTCACTAACTCTTCTTTTAGCCAGCTCTTTCGTAGAAAGAGGAGCTGGGACAGGATGAACGGTTTATCCCCCATTAGCATCAGGAATTGCCCATGCAGGGGCAGCCGTAGATTTA---GCTATTTTTAGTCTCCACCTTGCTGGGGTATCCTCAATTTTAGGTGCTGTAAATTTTATTACTACAGTAATTAATATGCGATCACCAGGTATAACTTTTGATCGAATACCTCTATTTGTTTGAGCTGTTGCTATTACTGCTCTCCTTCTTCTTCTCTCTTTACCAGTTTTAGCTGGA---GCTATTACTATACTTCTTACAGATCGTAATTTAAATACCTCATTCTTTGATCCAGCCGGAGGAGGAGACCCTATTTTATATCAACATTTATTCTGATTCTTTGGTCACCCTGAAGTCTATATTTTAATCCTTCCGGGATTCGGAATAATTTCACACATTATTAGTCAAGAAAGTGGAAAAAAG---GAAACTTTTGGATCTTTAGGAATAATTTATGCTATACTAGCCATTGGATTATTAGGATTTATTGTATGAGCACACCATATATTTACAGTAGGTATAGATGTTGATACCCGGGCCTACTTTACTTCAGCTACAATAATTATTGCTGTTCCTACAGGAATTAAAATTTTTAGTTGACTA---GCAACTCTCCACGGATCT---CAAATTAATTATAGCCCTGCTTTACTCTGAGCCTTAGGATTCATTTTCTTATTTACAGTCGGGGGTTTAACTGGTGTTGTACTAGCCAATTCTTCTATTGATATTATTCTTCACGACACATATTATGTAGTTGCCCACTTCCATTATGTT---TTATCAATAGGAGCAGTATTTGCTATCATGGGGGGATTCATTCATTGATACCCCTTATTTTCAGGATTATCTATAAACCCTAATTGATTAAAAATCCAATTCTTAATTATATTCATTGGGGTAAATCTTACCTTCTTTCCTCAACATTTTTTAGGATTAAGAGGTATGCCTCGA---CGATACTCAGATTACCCTGACGCCTATACT---TCTTGAAATGTTGTTTCTTCAATTGGATCTACAATTTCATTAGTAGGTGTTATTTTTTTCCTATTTATTGTATGAGAAAGAATGGTTTCTCATCGATCAATT---TTATTCCCAACTCATGCTCCTTCTTCT
-- end --

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Statistics of barcoding coverage: Corydalus cornutus

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 3
Specimens with Barcodes: 5
Species With Barcodes: 1
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Conservation

Conservation Status

This species is wide-spread. It is not generally considered in need of special conservation protection.

IUCN Red List of Threatened Species: not evaluated

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

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This species is wide-spread. It is not generally considered in need of special conservation protection.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

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National NatureServe Conservation Status

United States

Rounded National Status Rank: NNR - Unranked

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NatureServe Conservation Status

Rounded Global Status Rank: GNR - Not Yet Ranked

Reasons: It can be found throughout the southwestern portion of the United States west of the Rocky Mountains into Mexico and Guatemala.

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National NatureServe Conservation Status

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: NNR - Unranked

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NatureServe Conservation Status

Rounded Global Status Rank: GNR - Not Yet Ranked

Reasons: It is widespread from Texas and New Mexico, north and east throughout the Midwest and eastern United States and into parts of southeastern Canada.

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Relevance to Humans and Ecosystems

Benefits

Economic Importance for Humans: Negative

Though people are sometimes frightened by the large size and fierce appearance of adult dobsonflies, they are quite harmless. The larvae can deliver a painful bite in self-defense.

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Economic Importance for Humans: Positive

This species is sometimes used as bait by fishermen. It is also a natural enemy of some insects pests, especially Simuliidae.

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Economic Importance for Humans: Negative

Though people are sometimes frightened by the large size and fierce appearance of adult dobsonflies, they are quite harmless. The larvae can deliver a painful bite in self-defense.

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Economic Importance for Humans: Positive

This species is sometimes used as bait by fishermen. It is also a natural enemy of some insects pests, especially blackflies.

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Wikipedia

Corydalus cornutus

Mounted female specimen from the entomological collection of Muséum de Toulouse

The eastern dobsonfly, Corydalus cornutus, is a large insect in the Corydalidae family. It is found in eastern North America in regions with fast-flowing streams where its aquatic larvae develop. These are known as hellgrammites and are among the top invertebrate predators in the streams in which they live. They are used by anglers as bait.[1]

Distribution[edit source | edit]

The dobsonfly is found in most of eastern North America. It is usually found near the swift flowing, unpolluted streams in which its larvae develop.[1]

Larva

Description[edit source | edit]

The eggs are grey and cylindrical, about 1.4 millimetres long and 0.5 millimetres wide. They are laid in groups of about 1,000, stacked in three layers. The pile of eggs is protected by a clear fluid which dries white and is applied by the female with the tip of her abdomen. The egg mass is said to look rather like a bird dropping.[2]

The larvae are light brown with a covering of tiny dark brown microspines. The thorax has three pairs of legs and each segment is covered by a tough, dark-coloured dorsal plate.[3] The first eight abdominal segments have lateral tactile filaments and the first seven have tracheal gills in tufts.[4] The larvae also have spiracles allowing them to breathe on land as well as in the water. At the tip of the abdomen there are two prolegs, each with a dorsal filament and a pair of terminal hooks which enables the larva to anchor itself in fast-flowing water. The mandibles are sclerotised and powerful.[1]

The pupae are orange in colour with dark patches on the upper side of the abdomen and are covered with minute bristles. The developing limbs, wings and antennae project outside the pupal covering.[1]

The adult dobsonfly is a large insect up to 140 millimetres long with a wingspan of up to 125 millimetres.[5] 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 40 millimetres long, half as long as the body.[1] The antennae are long and segmented and the greyish translucent, many veined wings are often mottled with white dots. When at rest the wings are folded flat over the insect's back and extend beyond the abdomen.[6]

Life cycle[edit source | edit]

Dobsonfly eggs are usually laid close to the water's edge on a rock or overhanging foliage and hatch at night one to two weeks later. The newly emerged larvae fall or crawl into the stream and make their way to a fast-flowing section with a stony bottom. They are called hellgrammites and they hide under stones, catching and eating soft-bodied invertebrates.[7] They grow slowly, shedding their skins ten to twelve times and reaching a length of up to ninety millimetres. The larger hellgrammites are fearsome predators with well-developed jaws. After one to three years and when ready to pupate, they emerge from the water and travel up to fifteen metres looking for a suitable location under a rock, log or leaf litter.[8] There may be a mass emergence of hellgrammites within a few days of each other.[9] Each one digs a hole in moist soil and prepares a small, smooth walled chamber, and after a prepupal stage of a few days, sheds their skin and pupates. In some areas the adults emerge in seven to fourteen days [1] but in other areas they overwinter as pupae.[10] On emerging, they dig their way to the surface. They are not thought to feed as adults but spend their time in dense vegetation near streams. They are most active at night and are attracted by lights. They mate and lay their eggs, usually dying within a week.[1]

References[edit source | edit]

  1. ^ a b c d e f g Featured Creatures
  2. ^ Baker, J. R. and H. H. Neunzig. 1968. The egg masses, eggs and first-instar larvae of the eastern North American Corydalidae. Annals of the Entomological Society of America 61: 1181-87.
  3. ^ Neunzig, H. H. and J. R. Baker. Order Megaloptera. 1991. In: Stehr, F. W., editor. Immature Insects, Vol. 2. Kendall/Hunt Publishing Company. Dubuque, Iowa. pp. 112-22.
  4. ^ Barclay, A., et al. 2005. Tracheal gills of the dobsonfly larvae, or hellgrammite Corydalus cornutus L. (Megaloptera: Corydalidae). Journal of the Kansas Entomological Society 78: 181-85.
  5. ^ BugGuide
  6. ^ Field Guide to Texas Insects
  7. ^ McCafferty, W. P. and A. V. Provonsha. 1983. Aquatic Entomology: The Fisherman's and Ecologist's Illustrated Guide to Insects and Their Relatives. Jones and Bartlett Publishers, Inc. Portola Valley, California. 448 pp.
  8. ^ Mangan, B. P. 1994. Pupation ecology of the dobsonfly Corydalus cornutus (Corydalidae: Megaloptera) along a large river. Journal of Freshwater Ecology 9: 57-62.
  9. ^ Voshell, J. R. 2002. A Guide to Common Freshwater Invertebrates of North America. The McDonald & Woodward Publishing Company. Blacksburg, Virginia. 442 pp.
  10. ^ Eastern Dobsonfly. Fairfax County Public Schools.
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