Grasshoppers: The Family Acrididae

Grasshoppers: The Family Acrididae

Their Life Cycle, Mating Habits, and Place in Folklore

  • B.A., Political Science, Rutgers University

Most grasshoppers that you find in your garden, along the side of the road, or perhaps while walking through a summer meadow belong to the family Acrididae. The group is subdivided into several subfamilies that include slant-faced grasshoppers, stridulating grasshoppers, Band-winged grasshoppers, and some of the better-known locusts. Most of the 11,000 or so species grasshoppers are medium to large in relation to other insects but members of this huge family vary greatly in size, ranging from less than half-an-inch to more than three inches in length. Since many are gray or brown in color, they are easily camouflaged by the vegetation in their natural habitats.

In the Acrididae family, the «ears,» or auditory organs, are located on the sides of the first abdominal segments and are covered by the wings (when present). Their antennae are short, typically extending less than half the grasshopper’s body length. A plate-like structure called the pronotum covers the grasshopper’s thorax, or chest, never extending beyond the base of the wings. The tarsi, or back legs, have three segments.

Classification

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Orthoptera
  • Family: Acrididae

The Grasshopper Diet: Eating and Eaten

Grasshoppers commonly feed on plant foliage, with a particular fondness for grasses and spurges. When grasshopper populations become large, swarms of them can defoliate grasslands and agricultural crops over large areas.

In addition to natural predators, grasshoppers are consumed as human food in many countries, including Mexico, China, and nations in Africa and the Middle East.

Life Cycle

Grasshoppers, like all members of the order Orthoptera, undergo simple or incomplete metamorphosis with three life stages: egg, nymph, and adult.

  • Egg: Female grasshoppers lay fertilized eggs in midsummer, covering them with a sticky substance that dries to create an egg pod. Pods contain between 15 to 150 eggs, depending on the species. One female grasshopper may lay up to 25 pods. The eggs remain buried beneath one to two inches of sand or leaf litter for about 10 months over autumn and winter, hatching into nymphs in spring or early summer.
  • Nymph: Grasshopper nymphs, a.k.a. molts, resemble adult grasshoppers, except they lack wings and reproductive organs. Nymphs begin feeding on plant foliage as soon as one day after hatching from the egg and undergo five substages of development, known as instars before reaching full maturity. During each instar, nymphs shed their skin cuticles (molt) and their wings continue to grow. It takes five to six weeks for a nymph to mature into an adult grasshopper.
  • Adult: After the final molt, it may still take a month before an adult grasshopper’s wings are fully developed. While their reproductive organs are fully grown, female grasshoppers do not lay eggs until they’re about a week or two into adulthood. This allows lets them gain enough bodyweight to accommodate egg-laying. Once a female begins laying eggs, she continues to do so every three to four days until she dies. The lifespan of an adult grasshopper is about two months, depending on the weather and other factors such as predation.

Interesting Behaviors

  • Many male grasshoppers in the family Acrididae employ courtship calls to attract mates. Most of them use a form of stridulation, in which they rub pegs on the inside of their hind legs against a thickened edge of the wing to create their familiar songs.
  • Band-winged grasshoppers snap their wings while in flight, making an audible crackle.
  • In some species, the male may continue to guard the female after mating, riding on her back for a day or more to discourage her from mating with other males.

Range and Distribution:

Most Acridid grasshoppers inhabit grasslands, although some live in forests or even habitats that feature aquatic vegetation. More than 11,000 species have been described worldwide, with more than 600 of them living in North America.

Grasshoppers in Folklore

The ancient Greek storyteller Aesop is credited with «The Ant and the Grasshopper,» a tale in which an ant works hard preparing for winter while the grasshopper plays. When winter comes, the grasshopper asks for shelter and food from the ant, who refuses, leaving the grasshopper to starve.

The folklore of many Native American tribes includes grasshoppers. The insects’ roles in these stories vary greatly, depending on whether the tribe is an agrarian or hunter-gatherer society. In agrarian cultures, grasshoppers are viewed in a negative context, since swarms of them often decimated crops. They’re often portrayed as lazy, shiftless, or greedy characters, and they’re also associated with bad luck or discord. (Amongst the Hopi, grasshoppers are said to nip the noses of children who disobey elders or violate tribal taboos.)

Grasshoppers fare much better in the folk traditions of hunter-gather tribes, who imbued them with the powers not only to predict the weather—but to change it outright—bringing rain to end a drought, or causing rain to cease during a deluge.

www.thoughtco.com

Grasshoppers, Crickets, and Katydids, Order Orthoptera

Habits and Traits of Grasshoppers and Crickets

  • B.A., Political Science, Rutgers University

If you’ve walked through the grass on a warm summer day, you’ve likely encountered members of the order Orthoptera—the grasshoppers, crickets, and katydids. Orthoptera means «straight wings,» but these insects would be better named for their characteristic jumping legs.

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Description

Crickets, grasshoppers, and katydids undergo incomplete or gradual metamorphosis. Nymphs look similar to mature adults but lack fully-developed wings.

Powerful hind legs, built for jumping, characterize the Orthopteran insects. The muscular legs propel grasshoppers and other members of the order for distances up to 20 times their body lengths.

Insects in the order Orthoptera are known for more than their jumping skills, however. Many are accomplished singers as well. Males of some species attract mates by producing sounds with their legs or wings. This form of sound production is called stridulation and involves rubbing the upper and lower wings or the hind leg and wing together to create a vibration.

When males call for mates using sounds, those species must also have «ears.» Don’t look at the head to find them, however. Grasshoppers have auditory organs on the abdomen, while crickets and katydids listen using their front legs.

Orthopterans are usually described as herbivores, but in truth, many species will scavenge other dead insects in addition to feeding on plants. The order Orthoptera is subdivided into two groups—Ensifera, the long-horned insects (with long antennae), and Caelifera, the short-horned insects.

Habitat and Distribution

Members of the order Orthoptera exist in terrestrial habitats throughout the world. Though often associated with fields and meadows, there are Orthopteran species that prefer caves, deserts, bogs, and seashores. Worldwide, scientists have described over 20,000 species in this group.

www.thoughtco.com

Entomology Today

Brought to you by the Entomological Society of America

Rise of the Grasshoppers: New Analysis Redraws Evolutionary Tree for Acrididae Family

For the first time ever, scientists have used molecular genetics to build a phylogeny—roughly akin to a family tree—for Acrididae, the largest taxonomic family of grasshoppers, offering new, more nuanced understanding of how grasshoppers have evolved. The family Acrididae comprises more than 6,700 species, including Adimantus ornatissimus. (Photo credit: Maria Marta Cigliano)

Grasshoppers are one of the most ubiquitous groups of insects in the world, found everywhere from grasslands to tropical rainforests to isolated mountain ranges to sandy deserts. And now, thanks to a decade-long analysis of grasshoppers’ genetic relationships, scientists have the clearest picture yet of the evolutionary pathways grasshoppers have followed to attain such diversity—and the findings put the birthplace of the broadest lineage of grasshoppers in South America, not Africa, as previously thought.

To conduct the study, a team of researchers at Texas A&M University and the Museo de La Plata in Argentina gathered grasshopper specimens from 22 countries and extracted DNA samples. Drawing from 142 grasshopper species, the researchers analyzed nucleotide sequences of both nuclear and mitochondrial genomes from those samples to learn how the various grasshopper species from around the world are related. The findings from study, the first-ever such genetic analysis of Acrididae as a whole, are published today in Insect Systematics and Diversity.

“We used the differences in nucleotides among different species to infer the relationships,” says Hojun Song, Ph.D., associate professor of entomology at Texas A&M and lead author on the study. “For example, closely related species will share similar stretches of nucleotides because they share a common ancestor, but distantly related species will have more different nucleotides between them.”

The resulting phylogeny—roughly akin to a family tree, but in this case for Acrididae, the largest taxonomic family of grasshoppers—gives science a new, more nuanced understanding of how grasshoppers have evolved. It shows that grasshoppers within Acrididae descended and diversified from one common ancestor, but many of the currently recognized subfamilies are deemed “paraphyletic,” meaning they couldn’t be narrowed down to their own single common ancestor on the Acrididae family tree.

By analyzing nucleotide sequences of both nuclear and mitochondrial genomes of grasshoppers, a team of researchers has built a phylogeny for Acrididae, the largest taxonomic family of grasshoppers. This new “family tree” for Acrididae suggests the lineage originated in South America, and it also finds that many subfamilies within Acrididae as currently classified need revision. Grasshopper taxonomy long been difficult due to physical similarities between species, but genetic analysis offers a new tool for enhanced taxonomists to improve their understanding of how grasshoppers’ broad diversity evolved. (Image originally published in Song et al 2018, Insect Systematics and Diversity)

Historically, grasshopper taxonomy has been difficult due to convergent evolution, in which organisms that are not closely related evolve similar external features and appearance as they adapt to similar environments. Thus, taxonomists commonly grouped unrelated species into the same groupings due to their similar convergent body forms. Meanwhile, often only minute physical differences exist between species, leading taxonomists to rely on male grasshopper genitalia as the leading identifier to differentiate species. But Song and colleagues say their genetic analysis offers a new lens through which taxonomists may look to revisit grasshopper classification.

“There are some subfamilies, such as Catantopinae and Hemiacridinae, that have been considered taxonomic dumping ground for many decades,” Song says. “This means that a lot of unrelated groups have accumulated in these artificial groupings. Showing the paraphyletic nature of these groups is the first step to reclassify taxonomy, and we foresee that there would be some major shifts in grasshopper classification in the near future.”

Perhaps the most significant of those shifts is the determination that the common ancestor of grasshoppers in the Acrididae family lived in South America, not Africa. Scientists used to think that Acrididae originated from Africa because many other related families exist in Africa and because the South American grasshoppers had not been fully explored. The genetic analysis included samples from eight species outside but related to those in Acrididae. Among those “outgroup” species sampled, the ones deemed most closely related in the genetic analysis are all native to South America. The researchers also studied fossil specimens to calibrate the age of certain grasshopper subfamilies, and they found that the earliest diverging lineage within the Acrididae family is also primarily found in South America.

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“These relationships collectively point to the South American origin of this cosmopolitan family,” Song says. “Our time-calibrated tree shows that Acrididae originated in the Paleocene of the Cenozoic period, 59.3 million years ago.”

At that point in history, the continents of South America and Africa were already separated but closer compared to their current positions, and northern Africa was covered in tropical rainforests, much like the Amazonian region in South America. Song and colleagues propose that Acrididae’s single ancestor first branched off from its relatives in South America and then traversed the Atlantic sometime around 57 million years ago. Those grasshopper “colonists” found suitable habitat in Africa and then rapidly radiated and diversified across Africa and into Europe and Asia. After that, the genetic analysis points to at least three subsequent recolonization events in which grasshoppers traversed back to North America, furthering their global spread and diversification.

Diversity of Acrididae: (A) Anacridium aegyptium, (B) Dactylotum bicolor, (C) Kosciuscola tristis, (D) Adimantus ornatissimus, (E) Calliptamus italicus, (F) Proctolabus mexicanus, (G) Marellia remipes, (H) Paulinia acuminata, (I) Acrida sp., (J) Hylopedetes surdus, (K) Trimerotropis pallidipennis, (L) Stenopola puncticeps, (M) Rhammatocerus pictus, (N) Abracris flavolineata, (O) Hemiacris fervens. (Photo credits. A, E, I, N: Ruben Foquet; B, O: Ricardo Mariño-Pérez; C, J: Hojun Song; D, L, M: Maria Marta Cigliano; F, K: Paolo Fontana; G, H: Juan Manuel Cardona. Originally published in Song et al 2018, Insect Systematics and Diversity)

Given grasshoppers’ iconic status in the insect realm, Song says he was surprised that no one had previously attempted to build a phylogeny of Acrididae through molecular genetic techniques. The new effort was made possible by grants, dating back to 2008, from the National Science Foundation for Song’s research into the evolution of Orthoptera, the insect order comprising grasshoppers and their relatives such as locusts, crickets, and katydids. Before such a phylogenetic project can even begin, years of field work is necessary to collect the broad range of sample species needed, aided by contributions from international collaborators, as well.

“It is not an overstatement to say that this study took 10 years to complete,” Song says. “This type of research requires extensive taxon sampling to appropriately represent the known diversity, which is probably the most challenging—but also the most exciting—aspect of any large-scale phylogenetic study.”

Acrididae is known to contain approximately 6,700 species. And so, while the new genetic analysis is the most detailed yet on the grasshopper family, the species it sampled constitute only 2 percent of Acrididae’s full diversity. Song says he and his colleagues are eager to further build out the grasshopper family tree.

“We plan to increase the taxon sampling in the future and use more phylogenetic markers to build a more comprehensive phylogeny. At the same time, we plan to reclassify major groups within the family so that the classification would reflect monophyletic groups,” he says.

Read More

Insect Systematics and Diversity

entomologytoday.org

Insects in the acrididae family

Grasshoppers or Locusts

Most commonly called grasshoppers, species in this family vary greatly in shape, size and colouring but all possess large hind legs well developed for jumping. They have short antennae, a short ovipositor and well-developed wings. Grasshoppers are active during the day and can produce sound by rubbing a row of pegs located on the hind legs against part of the forewings. Most species feed on grass (as their name suggest), but other vegetation is also consumed including leaves, stems and even dead eucalyptus leaves.

The name locust is given to those species that are known to build up in large numbers. Locust swarms then migrate across large areas causing almost complete destruction to all green vegetation, especially agricultural crops.

Female grasshoppers and locusts generally lay their eggs in a mass in the ground by extending their short ovipositors through the soil surface. On hatching the young resemble adult but are smaller and have no wings. Wings slowly develop over a series of moults.

Chortoicetes termifera (Australian plague locust)

The Australian plague locust is a native species of Australia and is one of the most economically important species in Australia. At times this species is known to build up in great numbers forming swarms that migrate across central and eastern Australia eating their way through almost anything green. This species can be recognised by the black patch on the tip of the hind wing and the red colouring on its hind leg. The body of female Australian plague locusts is usually green, but when swarming is brownish in colour.

Urnisa guttulosa (salt and pepper grasshopper)

Urnisa guttulosa is sometimes known as the salt and pepper grasshopper and its reddish colouring is a reflection of its preferred environment. This species is widespread across the arid to semiarid areas of the country and is usually found in sandy environments. This is an alert and quick-moving grasshopper that will take to the wing readily when disturbed.

Gastrimargus musicus (yellow winged locust)

For more grasshopper and locust species visit the A ustralian I nsect C ommon N amesAcrididae section found here.

www.ento.csiro.au

Study of genetic relationships in grasshopper family Acrididae points to South American origin

Grasshoppers are one of the most ubiquitous groups of insects in the world, found everywhere from grasslands to tropical rainforests to isolated mountain ranges to sandy deserts. And now, thanks to a decade-long analysis of grasshoppers’ genetic relationships, scientists have the clearest picture yet of the evolutionary pathways grasshoppers have followed to attain such diversity—and the findings put the birthplace of the broadest lineage of grasshoppers in South America, not Africa, as previously thought.

See also:  Beetle barbel insect

To conduct the study, a team of researchers at Texas A&M University and the Museo de La Plata in Argentina gathered grasshopper specimens from 22 countries and extracted DNA samples. Drawing from 142 grasshopper species, the researchers analyzed nucleotide sequences of both nuclear and mitochondrial genomes from those samples to learn how the various grasshopper species from around the world are related. The findings from study, the first-ever such genetic analysis of Acrididae as a whole, are published today in Insect Systematics and Diversity.

«We used the differences in nucleotides among different species to infer the relationships,» says Hojun Song, Ph.D., associate professor of entomology at Texas A&M and lead author on the study. «For example, closely related species will share similar stretches of nucleotides because they share a common ancestor, but distantly related species will have more different nucleotides between them.»

The resulting phylogeny—roughly akin to a family tree, but in this case for Acrididae, the largest taxonomic family of grasshoppers—gives science a new, more nuanced understanding of how grasshoppers have evolved. It shows that grasshoppers within Acrididae descended and diversified from one common ancestor, but many of the currently recognized subfamilies are deemed «paraphyletic,» meaning they couldn’t be narrowed down to their own single common ancestor on the Acrididae family tree.

Historically, grasshopper taxonomy has been difficult due to convergent evolution, in which organisms that are not closely related evolve similar external features and appearance as they adapt to similar environments. Thus, taxonomists commonly grouped unrelated species into the same groupings due to their similar convergent body forms. Meanwhile, often only minute physical differences exist between species, leading taxonomists to rely on male grasshopper genitalia as the leading identifier to differentiate species. But Song and colleagues say their genetic analysis offers a new lens through which taxonomists may look to revisit grasshopper classification.

«There are some subfamilies, such as Catantopinae and Hemiacridinae, that have been considered taxonomic dumping ground for many decades,» Song says. «This means that a lot of unrelated groups have accumulated in these artificial groupings. Showing the paraphyletic nature of these groups is the first step to reclassify taxonomy, and we foresee that there would be some major shifts in grasshopper classification in the near future.»

Perhaps the most significant of those shifts is the determination that the common ancestor of grasshoppers in the Acrididae family lived in South America, not Africa. Scientists used to think that Acrididae originated from Africa because many other related families exist in Africa and because the South American grasshoppers had not been fully explored. The genetic analysis included samples from eight species outside but related to those in Acrididae. Among those «outgroup» species sampled, the ones deemed most closely related in the genetic analysis are all native to South America. The researchers also studied fossil specimens to calibrate the age of certain grasshopper subfamilies, and they found that the earliest diverging lineage within the Acrididae family is also primarily found in South America.

«These relationships collectively point to the South American origin of this cosmopolitan family,» Song says. «Our time-calibrated tree shows that Acrididae originated in the Paleocene of the Cenozoic period, 59.3 million years ago.»

At that point in history, the continents of South America and Africa were already separated but closer compared to their current positions, and northern Africa was covered in tropical rainforests, much like the Amazonian region in South America. Song and colleagues propose that Acrididae’s single ancestor first branched off from its relatives in South America and then traversed the Atlantic sometime around 57 million years ago. Those grasshopper «colonists» found suitable habitat in Africa and then rapidly radiated and diversified across Africa and into Europe and Asia. After that, the genetic analysis points to at least three subsequent recolonization events in which grasshoppers traversed back to North America, furthering their global spread and diversification.

Given grasshoppers’ iconic status in the insect realm, Song says he was surprised that no one had previously attempted to build a phylogeny of Acrididae through molecular genetic techniques. The new effort was made possible by grants, dating back to 2008, from the National Science Foundation for Song’s research into the evolution of Orthoptera, the insect order comprising grasshoppers and their relatives such as locusts, crickets, and katydids. Before such a phylogenetic project can even begin, years of field work is necessary to collect the broad range of sample species needed, aided by contributions from international collaborators, as well.

«It is not an overstatement to say that this study took 10 years to complete,» Song says. «This type of research requires extensive taxon sampling to appropriately represent the known diversity, which is probably the most challenging—but also the most exciting—aspect of any large-scale phylogenetic study.»

Acrididae is known to contain approximately 6,700 species. And so, while the new genetic analysis is the most detailed yet on the grasshopper family, the species it sampled constitute only 2 percent of Acrididae’s full diversity. Song says he and his colleagues are eager to further build out the grasshopper family tree.

«We plan to increase the taxon sampling in the future and use more phylogenetic markers to build a more comprehensive phylogeny. At the same time, we plan to reclassify major groups within the family so that the classification would reflect monophyletic groups,» he says.

phys.org

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