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Rhopalosiphum maidis

What do they look like?

Like all aphids, corn leaf aphids are oval-shaped; they have soft bodies and a pair of tubes, known as cornicles, sticking out of the end of their abdomen. They are olive blue to bluish-green, and have short antennae and dark legs. Some corn leaf aphids have wings, although others do not. On average, they are 2.56 mm long. In the nymph stage, corn leaf aphids look like adults, only smaller. Members of this species can have many different shapes and sizes. (Bhardwaj, 2012; Woehrmann and Hales, 1989; van Emden and Harrington, 2007)

  • Average length
    2.56 mm
    0.10 in

Where do they live?

Corn leaf aphids (Rhopalosiphum maidis) are native to Asia, although they have spread almost worldwide. They are now found in the Nearctic, Ethiopian, Australian, and Neotropical regions, as well as some Oceanic islands, such as Hawaii. They are widespread across the United States, Mexico, the Middle East, and Europe, as well as the southern half of Canada and Asia, and parts of Africa. (Helmi, 2011; Jarasova, et al., 2013; Messing, et al., 2007; Mushtaq, et al., 2013; Parry, et al., 2012; Razmjou and Golizadeh, 2010; van Emden and Harrington, 2007)

What kind of habitat do they need?

Corn leaf aphids are found wherever their host plants grow, which includes cereals and grasses. Their habitats include agricultural fields and grasslands. They are one of the biggest cereal pests, although their range is restricted because they cannot survive in extremely cold winters. (Parry, et al., 2012; Razmjou and Golizadeh, 2010)

How do they grow?

Corn leaf aphids are hemimetabolous, meaning that they go through an egg, nymph, and adult stage. Females give birth to live young via parthenogenesis, which is a method of reproducing that does not involve mating. Offspring go through 4 development stages, known as instars, each instar lasts about two days, and then the aphids become adults. They may become adults as quickly as 7 to 8 days after being born. They develop fastest in warmer temperatures. (Kuo, et al., 2006; Park and Obrycki, 2004; Razmjou and Golizadeh, 2010; Sharma and Bhatnagar, 2002)

How do they reproduce?

Corn leaf aphids only reproduce by parthenogenesis; this asexual method of breeding involves no mating or fertilization by males, and produces identical young. A few populations of mating corn leaf aphids have been found in Pakistan among groups that only feed on Himalayan prune cherries (Prunus cornuta). In other colonies, males are sometimes produced, but they do not mate. (van Emden and Harrington, 2007)

Corn leaf aphids produce live young by parthenogenesis, which is asexual reproduction without mating. This means that females produce genetically-identical clones, without being fertilized by males. Females produce the most offspring when the temperature is around 20 to 25 degrees Celsius. A female can have anywhere from 5 to 75 offspring in her lifetime. Corn leaf aphids can reach maturity in about 7 to 8 days. The colony is largest and the most offspring are produced during July, or later in their host plant's growing season, depending on where they are found. (Kuo, et al., 2006; Park and Obrycki, 2004; Sharma and Bhatnagar, 2002; van Emden and Harrington, 2007)

  • How often does reproduction occur?
    This species is parthenogenic and does not breed.
  • Breeding season
    Colony size and parthenogenesis typically peaks in mid-summer.
  • Range eggs per season
    5 to 75
  • Range age at sexual or reproductive maturity (female)
    7 (low) days

Females give birth to live offspring, which likely takes a large amount of energy. Since corn leaf aphids live in large colonies, their offspring immediately join the colony. Female parents may come in contact with their offspring, but they do not offer any parental care. (van Emden and Harrington, 2007)

  • Parental Investment
  • pre-hatching/birth
    • provisioning
      • female

How long do they live?

Adult corn leaf aphids generally live for a few weeks to a little over a month. Their lifespan tends to be longer at warmer temperatures. (Kuo, et al., 2006; Sharma and Bhatnagar, 2002)

  • Typical lifespan
    Status: wild
    12 to 35 days

How do they behave?

Like all aphid species, corn leaf aphids live in large colonies on their host plants. These colonies typically only include females and their identical offspring. Colonies can become large very fast because they reproduce without mating and they mature quickly. Some corn leaf aphids have wings, although some do not. The movement pattern of corn leaf aphids varies by population and region. Many colonies overwinter in warmer, southern areas, then migrate north in the spring when temperatures warm up. In India, some populations migrate at night using the wind, which shows they are sometimes active at night. Some populations also use a secondary host when their primary sources are not available. (Hesler and Dagel, 2010; Kuo, et al., 2006; Reynolds and Wilson, 1989; van Emden and Harrington, 2007)

Home Range

The exact home range size of corn leaf aphids is unknown. Since many of their colony members are wingless, their home range is probably limited to their host plants and the nearby areas. Some colonies move from primary to secondary host plants throughout the year, while other colonies overwinter in warmer regions and move to colder regions when the temperature warms up. Winged aphids are not usually strong fliers, and do not fly long distances except on air currents. Their home range is likely different in different regions. (Hesler and Dagel, 2010; Kuo, et al., 2006; van Emden and Harrington, 2007)

How do they communicate with each other?

Aphids view their environment visually, and prefer yellow surfaces. When a predator is nearby, aphids produce an alarm pheromone that alerts other aphids that danger is present. The release of their alarm pheromone usually causes the aphids to try and escape by walking away or falling off of the plant. Aphids can also detect chemicals specific to their host plants. Corn leaf aphids can detect when a plant is damaged, and will avoid feeding. When it is damaged, corn releases the same chemicals as the aphid alarm pheromone, which keeps aphids away and prevents further damage to the plant. (Bernasconi, et al., 1998; van Emden and Harrington, 2007)

What do they eat?

Like all aphids, corn leaf aphids feed on a plant tissue known as phloem. They use their mouthparts to pierce the plant vessels and suck out the sap. Corn leaf aphids have many possible host plants. They are a significant cereal and grass pest. They often use corn as their host plant (Zea mays), which gives corn leaf aphids their common name. They also feed on sorghum (Sorghum bicolor), barley (Hordeum vulgare), oats (Avena), wheat (Triticum), and plants from the families Gramineae, Cyperaceae, and Typhaceae, as well as many other grasses and cereals. They feed on the seedlings and leaves of these plants. These aphids may damage the plants on which they feed. (Razmjou and Golizadeh, 2010; van Emden and Harrington, 2007)

  • Primary Diet
  • herbivore
    • eats sap or other plant foods
  • Plant Foods
  • sap or other plant fluids

What eats them and how do they avoid being eaten?

Corn leaf aphids are preyed on by both larvae and adult lady beetles, including Propylea japonica, Propylea quatuordecimpunctata, Anegleis cardoni, Cheilomenes sexmaculata, members of genus Hippodamia, and many members of genus Coccinella. Many other insect species also prey on corn leaf aphids, including green lacewings, such as Chrysoperla nipponensis and larvae of Chrysoperla carnea, as well as several species of Syrphidae flies. Other predators include spiders and some bird species. Corn leaf aphids have very few ways to defend themselves. Having a large colony size decreases the threat to individual aphids. When attacked, aphids produce alarm pheromones to alert other individuals, in response, they try to escape. They are often hidden inside of corn while they feed, which keeps them protected. Red imported fire ants tend colonies of corn leaf aphids and protect them from predators and parasitoids, in return for feeding on the honeydew they produce. (Bunker and Ameta, 2009; Greenstone and Shufran, 2003; Khuhro, et al., 2012; Omkar, et al., 2011; Papanikolaou, et al., 2013; Park and Obrycki, 2004; Tremblay, et al., 2001; Vinson and Scarborough, 1991; Yan, et al., 2012; van Emden and Harrington, 2007)

What roles do they have in the ecosystem?

Corn leaf aphids are pests to cereals and grasses. They have many plant hosts, including corn, sorghum, barley, oats, and wheat, as well as plants of the families Gramineae, Cyperaceae, and Typhaceae. Their feeding habits and honeydew production can damage plants. These aphids also transmit many plant diseases. Corn leaf aphids have bacteria (Buchnera aphidicola) inside their bodies that produce the amino acids that they cannot get from their diet. Red imported fire ants tend colonies of corn leaf aphids, ants eat the honeydew produced by the aphids, while protecting and tending the colony from other predators. Red imported fire ants also remove and destroy parasitized aphids from the colony. Parasitoid wasps (Aphidius colemani) use these aphids as hosts. They lay their eggs inside the aphid's body, and after the aphid dies, the wasp hatches. These wasps can be used as a form of pest control to decrease crop damage. Other parasitoid wasps that use corn leaf aphids as hosts includes Lysiphlebus testaceipes, Lysiphlebia japonica, Aphidius colemani, and Lipolexis oregmae, along with many other wasp species. Parasitic fungi of order Entomophthorales also use corn leaf aphids as hosts. (Barta and Cagan, 2007; Dey and Akhtar, 2007; Rouhbakhsh, et al., 1996; Sampaio, et al., 2008; Vinson and Scarborough, 1991; van Emden and Harrington, 2007)

Species (or larger taxonomic groups) used as hosts by this species
  • corn (Zea mays)
  • sorghum (Sorghum bicolor)
  • barley (Hordeum vulgare)
  • oats (Avena)
  • wheat (Triticum)
  • grasses (Gramineae)
  • grasses (Typhaceae)
  • sedges (Cyperaceae)
Species (or larger taxonomic groups) that are mutualists with this species
Commensal or parasitic species (or larger taxonomic groups) that use this species as a host

Do they cause problems?

Corn leaf aphids are one of the biggest pests to cereals and grasses in mild and tropical areas. They feed on many important crops such as corn, wheat, barley, and oats. In large numbers, these aphids cause damage by feeding on plants and leaving large amounts of their honeydew behind. They also pass many plant diseases, including barley yellow dwarf virus (BYDV), sweet potato feathery mottle virus (SPFMV), millet red leaf virus (MRLV), sugarcane mosaic virus (SCMV), and maize dwarf mosaic virus (MDMV). There has been a lot of research on how to control their population and how to make crops resistant. (Jarasova, et al., 2013; Kuo, et al., 2006; Wosula, et al., 2013; van Emden and Harrington, 2007)

  • Ways that these animals might be a problem for humans
  • crop pest

How do they interact with us?

There are no known positive effects of corn leaf aphids on humans.

Are they endangered?

Corn leaf aphids have no special conservation status.


Angela Miner (author), Animal Diversity Web Staff, Leila Siciliano Martina (editor), Animal Diversity Web Staff.


Barta, M., L. Cagan. 2007. Natural control of Diuraphis noxia and Rhopalosiphum maidis (Aphidoidea) by parasitic entomophthorales (Zygomycota) in Slovakia. Cereal Research Communications, 35/1: 89-97.

Bernasconi, M., T. Turlings, L. Ambrosetti, P. Bassetti, S. Dorn. 1998. Herbivore-induced emissions of maize volatiles repel the corn leaf aphid, Rhopalosiphum maidis. Entomologia Experimentalis et Applicata, 87/2: 133-142.

Bhardwaj, M. 2012. Morphological studies on Aphid Fauna of Haryana as a tool for identification of different species. Journal of Entomological Research, 36/2: 251-254.

Bunker, G., O. Ameta. 2009. Predation potential of Coccinella septempunctata L., Cheilomenes sexmaculata F., and Chrysoperla carnea (Stephens) on different aphid species. Indian Journal of Entomology, 76/1: 76-79.

Dey, D., M. Akhtar. 2007. Diversity of natural enemies of aphids belonging to aphidiinae (Hymenoptera : Braconidae) in India. Journal of Asia-Pacific Entomology, 10/4: 281-296.

Greenstone, M., K. Shufran. 2003. Spider Predation: Species-Specific Identification of Gut Contents by Polymerase Chain Reaction. Journal of Arachnology, 31/1: 131-134.

Helmi, A. 2011. Identification of apterous viviparous of cereal aphids in Egypt (Hemiptera: Sternorrhyncha: Aphididae). Munis Entomology & Zoology, 6/1: 346-357.

Hesler, L., K. Dagel. 2010. Grass hosts of cereal aphids (Hemiptera:Aphididae) between wheat-cropping cycles in South Dakota. The Great Lakes Entomologist, 43/1: 1-10.

Jarasova, J., J. Chrpova, V. Sip, J. Kundu. 2013. A comparative study of the Barley yellow dwarf virus species PAV and PAS: distribution, accumulation and host resistance. Plant Pathology, 62/2: 436-443.

Khuhro, N., H. Chen, Y. Zhang, L. Zhang, M. Wang. 2012. Effect of different prey species on the life history parameters of Chrysoperla nipponensis (Neuroptera: Chrysopidae). European Journal of Entomology, 109/2: 175-180.

Kuo, M., M. Chiu, J. Perng. 2006. Temperature effects on life history traits of the corn leaf aphid, Rhopalosiphum maidis (Homoptera : Aphididae) on corn in Taiwan. Applied Entomology and Zoology, 41/1: 171-177.

Messing, R., M. Tremblay, E. Mondor, R. Foottit, K. Pike. 2007. Invasive aphids attack native Hawaiian plants. Biological Invasions, 9/5: 601-607.

Mushtaq, S., S. Rana, H. Khan, M. Ashfaq. 2013. Diversity and abundance of Family Aphididae from selected crops of Faisalabad, Pakistan. Pakistan Journal of Agricultural Sciences, 50/1: 103-109.

Omkar, , G. Kumar, J. Sahu. 2011. Monotypic prey-mediated development, survival and life table attributes of a ladybird beetle Anegleis cardoni (Coleoptera: Coccinellidae) on different aphid species. International Journal of Tropical Insect Science, 31/3: 162-173.

Papanikolaou, N., P. Milonas, D. Kontodimas, N. Demiris, Y. Matsinos. 2013. Temperature-Dependent Development, Survival, Longevity, and Fecundity of Propylea quatuordecimpunctata (Coleoptera: Coccinellidae). Annals of the Entomological Society of America, 106/2: 228-234.

Park, Y., J. Obrycki. 2004. Spatio-temporal distribution of corn leaf Aphids (Homoptera : Aphididae) and lady beetles (Coleoptera : Coccinellidae) in Iowa cornfields. Biological Control, 31/2: 210-217.

Parry, H., S. Macfadyen, D. Kriticos. 2012. The geographical distribution of Yellow dwarf viruses and their aphid vectors in Australian grasslands and wheat. Australasian Plant Pathology, 41/4: 375-387.

Razmjou, J., A. Golizadeh. 2010. Performance of corn leaf aphid, Rhopalosiphum maidis (Fitch) (Homoptera: Aphididae) on selected maize hybrids under laboratory conditions. Applied Entomology and Zoology, 45/2: 267-274.

Reynolds, D., M. Wilson. 1989. Aerial samples of micro-insects migrating at night over central India. Journal of Plant Protection in the Tropics, 6/2: 89-102.

Rouhbakhsh, D., C. Lai, C. von Dohlen, M. Clark, L. Baumann, P. Baumann, N. Moran, D. Voegtlin. 1996. The tryptophan biosynthetic pathway of aphid endosymbionts (Buchnera): Genetics and evolution of plasmid-associated anthranilate synthase (trpEG) within the Aphididae. Journal of Molecular Evolution, 42/4: 414-421.

Sampaio, M., V. Bueno, B. De Conti. 2008. The effect of the quality and size of host aphid species on the biological characteristics of Aphidius colemani (Hymenoptera: Braconidae: Aphidiinae). European Journal of Entomology, 105/3: 489-494.

Sharma, H., A. Bhatnagar. 2002. Biology of the maize aphid, Rhopalosiphum maidis (Fitch) on barley. Pest Management and Economic Zoology, 10/2: 111-114.

Tremblay, A., P. Mineau, R. Stewart. 2001. Effects of bird predation on some pest insect populations in corn. Agriculture, Ecosystems & Environment, 83/1-2: 143-152.

Vinson, S., T. Scarborough. 1991. Interactions between Solenopsis invicta (Hymenoptera, Formicidae), Rhopalosiphum maidis (Homoptera, Aphididae), and the parasitoid Lysiphlebus testaceipes Cresson (Hymenoptera, Aphidiidae). Annals of the Entomological Society of America, 84/2: 158-164.

Woehrmann, K., D. Hales. 1989. Life cycle components and genetic variability in aphids. Journal of Applied Entomology, 107/1: 71-77.

Wosula, E., J. Davis, C. Clark, T. Smith, R. Arancibia, F. Musser, J. Reed. 2013. The Role of Aphid Abundance, Species Diversity, and Virus Titer in the Spread of Sweetpotato Potyviruses in Louisiana and Mississippi. Plant Disease, 97/1: 53-61.

Yan, Z., C. Zhang, Z. Wang, K. He, S. Bai. 2012. Predatory function response of Propylea japonica on Rhopalosiphum maidis. Chinese Journal of Biological Control, 28/1: 139-142.

van Emden, H., R. Harrington. 2007. Aphids as Crop Pests. Trowbridge, United Kingdom: CABI.

University of Michigan Museum of ZoologyNational Science Foundation

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Miner, A. 2014. "Rhopalosiphum maidis" (On-line), Animal Diversity Web. Accessed October 22, 2017 at

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