Senegalese grasshopper (Oedaleus senegalensis)
| Oedaleus senegalensis | |
|---|---|
 | |
| Other common names | |
| Senegalese cross grasshopper, Criquet sénégalais (Fr), Panzi wa Senegali (Swahili) | |
| Taxonomic classification | |
| Suborder: | Caelifera |
| Family: | Acrididae |
| Subfamily: | Oedipodinae |
| Tribe: | Locustini |
| Genus: | Oedaleus |
| Scientific name | |
| Oedaleus senegalensis (Krauss, 1877) | |
| Geography | |
| Native countries: | |
| Pest status | |
| Known pest | |
Oedaleus senegalensis is commonly called the Senegalese grasshopper or locust and is a significant agricultural pest in the Sahel region of Africa.
Taxonomy
For full nomenclature and taxonomic details of this taxon, see Orthoptera Species File
Identification
The Senegalese grasshopper (Oedaleus senegalensis) is a species of band-winged grasshoppers (subfamily Oedipodinae, family Acrididae), a group characteristic of semi-arid grasslands. They are easily recognized by their large, lobed hindwings, often marked with spots or bands, which distinguish them from other grasshopper subfamilies. These hindwings also enable many species to produce a loud snapping crepitation during flight.
Identification details
Oedaleus senegalensis is a medium-sized grasshopper.[1] Fully grown adults typically measure between 2 and 4 centimeters in length and weigh less than 0.5 grams. Their coloration can vary, spanning from shades of green or tan to a dark brown, with dark markings. Shifts in color reflect ecological and humidity conditions with brown at the start and end of the rainy season to green at its peak.[2][3]within[4] Brown morphs dominate in fallow fields early in the rainy season, often occurring at higher densities.[5]
Their body is spotted with a distinctive X-shaped marking on the pronotum. The hindwings are yellow at the base with a black band that is complete or nearly complete but does not extend to the hind margin. The inner femur is white to yellow, while the hind tibiae range in color from pink to red. On the Cape Verde Islands, the variety O. senegalensis var. dimidiatus, displays darker coloration, with hindwings black all the way to the base. Across its range, O. senegalensis can be mistaken for O. nigeriensis, O. johnstoni, O. obtusangulus, O. flavus, or O. abruptus.[6][1][7]
Oedaleus nigeriensis differs from the Senegalese grasshopper by its more robust build and relatively shorter wings. Its pronotal margin is angled rather than rounded, and the inner hind femur is orange to red (compared to white or yellow in O. senegalensis). In addition, the dark band on the hindwings of O. nigeriensis is distinctly interrupted near the anterior margin.[8][1]
Oedaleus johnstoni can be distinguished from the Senegalese grasshopper by the black hindwing band, which reaches only the posterior margin. The inner surface of the hind femur is orange with a pale ring near the base, while the hind tibiae are orange on the inside and occasionally yellow on the outside.[8][1]
Oedaleus obtusangulus is a small, uncommon species in West Africa. It differs from the Senegalese grasshopper by having a sharply angled pronotal posterior margin (rounded in O. senegalensis). The inner hind femur is mostly yellowish-white rather than orange, and the hind tibiae are greyish-beige.[1]
Identification resources
| Title | Author(s) | Year | Geographic purview | URL |
|---|---|---|---|---|
| FAO locust handbook identification key | FAO Desert Locust Information Service and Food and Agriculture Organization of the United Nations | View URL | ||
| Pest grasshoppers and locusts in Senegal | Global Locust Initiative, United States Agency for International Development and Directorate of Plant Protection | 2020 | ||
| Management of pest grasshoppers and locusts in Mali | Global Locust Initiative, United States Agency for International Development and Directorate of Plant Protection | 2020 | ||
| Community management of pest grasshoppers and locusts in Senegal | Global Locust Initiative, United States Agency for International Development and Directorate of Plant Protection | 2020 | ||
| Locust identification in Niger | Global Locust Initiative, United States Agency for International Development, Directorate of Plant Protection, United Nations AGRHYMET Regional Center, Le Centre National de Lutte Antiacridienne and National Network of Agriculture Chambers of Niger | 2022 | View URL | |
| CIRAD pest locust website | The French Agricultural Research Centre for International Development | View URL |
Distribution
The distribution of Oedaleus senegalensis extends across the entire Indo-Saharan zone, from the Atlantic—including the Cape Verde Islands—eastward to central India.[4] It occupies regions receiving 200–1000 mm of annual rainfall[9][10] and ranges from the expansive Sahelian rangelands in the north, which provide millions of hectares suitable for grasshoppers, to the croplands of the south.[4]
For more information and distribution records see [GBIF]
Biology
In Africa, this species produces one to three generations depending on latitude. In West Africa, adults occur from June to November, with eggs diapausing through the dry season; overlapping generations are further influenced by young adult migration.[11]
In India, hatching begins in June–July, with adults present by late July and a second generation before November; eggs laid then diapause until the following year. In parts of the Middle East and North Africa with winter–spring rains, it is likely bivoltine.[11]
Although O. senegalensis is sometimes referred to as a locust and shows some locust traits, it should be distinguished from species with pronounced density-dependent phase polyphenism, such as the desert locust, which occurs in the same region. In the Sahelian belt, O. senegalensis typically completes three generations per year, timed with the rainy season. Successive generations develop farther north as the grasshoppers track the northward shift of the Intertropical Convergence Zone (ITCZ). Long nocturnal flights carried by seasonal winds facilitate these migrations: G1 and G2 are pushed northward on southwesterly currents as humidity rises, while G3 are carried back south on northerly winds as the ITCZ retreats. By this stage, third-generation adults often reach peak numbers, invading maturing cereal crops.[6][4]
Migrations likely help Senegalese grasshoppers avoid natural enemies and disease, access better food, and increase egg production. Southward movements at the onset of the dry season allow eggs laid in southern areas to develop earlier due to an earlier rainy season, boosting reproductive rates.[4][12]
Eggs of O. senegalensis are deposited in dry sand or silt, sometimes at high densities. Development from hatching to adult takes about five weeks, with hatching to oviposition lasting around 35 days. However, egg development is highly variable, influenced by season, diapause, and rainfall. Not all eggs in a pod hatch with the first rains, and even under uniform lab conditions, hatching times varies greatly among eggs in the same pod.[3] Decreasing day length from September appears to trigger the laying of diapausing eggs.[13] Remarkably, eggs from pods laid 22 months earlier have hatched in the lab, and some pods continued producing hoppers for more than 10 months under constant moisture, indicating diapause may last several months or even up to five years.[11] This variability in egg laying and hatching is considered an adaptation to erratic rainfall, serving as insurance against isolated showers that fail to sustain vegetation for hopper survival.[3]
The Senegalese grasshopper has five nymphal instars, which typically develop in about three weeks. At high population densities, this species displays early stages of gregarious behavior, often forming hopper bands and loose swarms. Nymphs may form “hopper bands” that move collectively, though less cohesively than true locust bands. Similarly, for adults, they may appear as swarms at high density but not as cohesive. Adults are nocturnal fliers, capable of covering up to 350 km in a single night to track rains and suitable breeding sites. When conditions are favorable and diapause is absent, the lifecycle of this species can be completed in under two months.[6]
Habitat and ecology
O. senegalensis occurs in dry savannahs, often on sandy soils in Africa and India, feeding broadly on grasses. In Somalia, it inhabits dunes and dry grass steppes. Primarily graminivorous, it feeds on whatever grasses are available.[11] In the West African Sahel, O. senegalensis primarily inhabits annual grasslands dominated by Poaceae species. Other species include Cenchrus biflorus (known as “cram-cram” in francophone Sahel countries), Aristida mutabilis, Aristida adscensionis (“sixweeks threeawn”), Eragrostis species (“lovegrass” or “canegrass”), Dactyloctenium aegyptium (“Egyptian crowfoot grass”), and Schoenefeldia gracilis, along with some woody and perennial species such as Aristida pallida.[4] Research in central Senegal found O. senegalensis feeding on Pennisetum pedicellatum (“bara”), Paspalum scrobiculatum (“dugubupitj” or “bird millet”), Pennisetum glaucum (millet), Eragrostis tremula, and Cenchrus biflorus (“cram-cram” or “xaxham”).[1]
Eggs are parasitized by flies such as Xeramoeba oophagus and Systoechus sp., as well as by a beetle (Mylabris sp.) and larvae of histerid and tenebrionid beetles. Both nymphs and adults face predation from lizards, snakes, and numerous bird species, including the white-throated bee-eater (Merops albicollis), cattle egret, and Abyssinian roller (Coracias abyssinica).[11]
Land-use change
Sahelian rangelands dominate the north, providing millions of hectares of suitable habitat for grasshoppers, while croplands are more common in the south. In recent decades, however, croplands have expanded northward into traditional rangelands due to growing population pressure and soil depletion in the south. This shift has heightened conflicts between farmers and herders and led to greater cereal crop losses from Senegalese grasshoppers.[4]
Management
Chemical insecticides, usually applied as ULV sprays, remain the main method of controlling Senegalese grasshoppers. In Niger and Senegal, aerial spraying is common when populations reach high densities, while local field officers often use hand-held or backpack sprayers. However, the success of these efforts varies and largely depends on available funding, since control is typically treated as a government responsibility.[6] In Senegal, management is carried out by La Direction de la Protection des Végétaux (DPV).
Control of the Senegalese grasshopper is most effective when focused on the first instar nymphs that hatch at the start of the rainy season, since these juveniles cause the most damage to seedlings. Targeting these early populations can greatly reduce later movements and outbreaks, thereby limiting millet head losses from third-generation adults at the end of the season.[4] To achieve this, areas with high concentrations of early instars must be located quickly, which requires detecting diapaused egg fields. Dry-season surveys (December–February) can reveal sites with high egg-pod densities, though large areas and limited resources make this challenging. Because monitoring during March–June overlaps with land preparation, it is rarely feasible. As a result, many countries struggle to implement preventive strategies, and control efforts are often delayed until outbreaks occur late in the season. At that stage, infestations are rapid and severe, requiring heavier treatments to protect ripening crops.[4]
Models developed over the past 30 years can predict Senegalese grasshopper outbreaks using previous population levels, egg pod densities, and rainfall patterns, but adoption has been limited. Monitoring first- and third-generation densities can also provide forecasts, though cost-effectiveness remains uncertain. Preventive control depends on consistent field surveys during the rainy season as adults track the ITCZ, but more research is needed to evaluate its long-term effectiveness.[6]
Management alternatives to synthetic chemicals do exist. For example, field trials in Senegal (2002–2004) and eastern Niger (1996–1997) evaluated the efficacy of the entomopathogenic fungus Metarhizium anisopliae var acridum for controlling the Senegalese grasshopper, alone and in combination with low doses of the pyrethroid cyhalothrin or compared with fenitrothion. In all trials, the fungal treatment produced a slower initial knockdown than chemical insecticides but caused long-lasting population suppression, with infective residues remaining active for up to three weeks. Mixing a small amount of pyrethroid with the fungus accelerated population reduction while maintaining the prolonged effect of the biopesticide and reducing environmental impact. Chemical treatments alone were rapid but often allowed grasshopper populations to rebound due to immigration. The fungus also reduced egg pod density and viability, contributing to longer-term control. Overall, these studies show that M. anisopliae—particularly when combined with low-dose insecticides—offers an effective, environmentally safer alternative to conventional chemical control for managing Senegalese grasshopper populations.[14][15]
Seedling damage can be mitigated by postponing the first weeding, but this strategy is effective only at relatively high grasshopper densities. Digging up and destroying egg pods is occasionally employed in control campaigns, though its impact is typically limited since locating a large proportion of the pods is challenging.[6]
Land management and soil fertility are closely linked to O. Senegalensis populations. Fields and grazing areas with low-nitrogen plants support higher locust densities, increasing crop damage. Therefore, improving soil quality could reduce locust pressure by increasing plant nitrogen which is not favorable to this species.[16][17] One way to improve soil quality is to increase soil organic matter. However, natural accumulation from livestock or native plants is often insufficient. Active soil management—through synthetic or organic fertilizers, Zai pits, composting, Quesungual systems, and agroecosystem diversification—may be more effective than passive fallow rotations, especially since fallow fields can harbor locusts. While adoption of conservation agriculture in Africa has been limited, these approaches could provide dual benefits: improving soil fertility and reducing pest prevalence.[16]
In lab and field studies on O. senegalensis, adding more nitrogen fertilizer to millet increased the plant’s protein compared with its carbohydrates. This change made the locusts less healthy: fewer females survived, and those that did laid smaller eggs. The locusts also preferred untreated plants with lower protein-to-carbohydrate ratios. The results suggest that grasshoppers, like O. senegalensis, that need lots of carbohydrates may struggle on high-protein plants.[18]
The USAID-supported “Bay Sa Waar” project (Communities for Sustainable Agriculture) implemented this research into practice by bringing together Senegalese and international partners. In a 2019 pilot in Senegalese villages of Gniby and Gossas, 100 farmers applied recommended fertilizer to test millet plots, which boosted yields by 46% and reduced O. senegalensis densities and damage by 34% and 52%, respectively.[1]
The Bay Sa Waar project also supported community-led monitoring, particularly by women, along the migratory route of O. senegalensis. The species is often attracted to light, so participants used light traps—bright lamps that draw flying locusts and grasshoppers at night, causing them to fall into a bucket of soapy water where they cannot escape. This approach helps expand early warning systems, guide targeted interventions, and empower local communities while complementing NPPO monitoring efforts. Farmers can use light traps in their fields to track grasshopper movements; step-by-step instructions for building a trap are available here.
Pest status
O. senegalensis is well adapted to tropical zones, where it is considered a major pest, though its economic impact is minimal or absent elsewhere.[11][4] Crop damage can be severe in affected areas, with cereal harvests sometimes completely destroyed at the milky stage. Seedlings are especially vulnerable, often necessitating repeated resowing.[11]
In the Sahel, the primary crop host is pearl millet, which is attacked mainly at the seedling stage by nymphs and at the milky-grain stage by adults.[6] Other reported host plants include barley, bulrush millet, cowpea, groundnut (minor damage), guinea corn, lucerne, maize, Tribulus alatus, watermelon, wheat, and long sandal. However, crop susceptibility varies: in one instance, watermelon, cluster bean, melon, moth bean, and sesame remained unaffected even when nearby bulrush millet suffered heavy attack.[11]
Outbreaks
In favorable years, the Senegalese grasshopper may resemble locust swarms, but they lack the same cohesion as true locusts.[6] Prior to 1974, the Senegalese grasshopper was not considered a major pest in the Sahel.[19] Its first major economic impact occurred during the massive outbreaks of 1974, following the early 1970s drought, which caused severe damage to food crops, particularly millet (Pennisetum spp.) [4]. During this outbreak, swarms were so dense that they filled houses, and people collected them for food. [11] Since then, O. senegalensis has consistently been recognized as the primary pest in the Sahelian region.[3] The species has caused repeated major outbreaks, notably in 1975, 1977, 1985, 1986, and 1989, with the 1986 outbreak being particularly severe. That year, aerial and ground-based insecticide treatments were applied over 3,385,500 ha of infested areas from Senegal to Chad. FAO 1987 in [3]
Outbreak media coverage
Organizations associated with the Senegalese grasshopper
| Organization name | Acronym | Website | Type | Focus | Focus keywords | Geographic purview |
|---|---|---|---|---|---|---|
| Global Locust Initiative | GLI | View | University | Research, Education, Information Hub | Sustainable development, Ecology, Nutrition, Social science, Natural sciences, Agriculture, Agroecology, Biology, Behavior, Biological control, Climate change, Education, Sustainability science, Geometric framework, Grazing, Governance, Food security, Arts and humanities, Land use management, Landscape ecology, Locusts, Migration, Phase polyphenism, Phenotypic plasticity, Soil science | United States, Senegal, Australia, China, Argentina, Bolivia, Paraguay, Uruguay, Mali |
| Ministry of Agriculture Sudan | View | Government | Agricultural development | Sudan | ||
| The French Agricultural Research Centre for International Development | CIRAD | View | Government | Education, Development, Research, Management | Forecasting, International development, Training, Agricultural development, Sustainable development, Natural sciences, Modeling, Monitoring, Research, Control, Community development | France |
Projects
Numerous research projects looking at how land-use practices influence the Senegalese grasshopper (Oedaleus senegalensis) have built on each other over the years, creating a wealth of knowledge on this system and opportunities for alternative management strategies. Learn more about research on the Senegalese grasshopper in West Africa
Featured resource
Resources
| Title | Author(s) | Year | Geographic purview | URL |
|---|---|---|---|---|
| Liste globale des pesticides autorisés par le Comité Sahélien des Pesticides | Permanent Interstates Committee for Drought Control in the Sahel | 2020 | View URL | |
| 2014 evaluation of field trials data on the efficacy and selectivity of insecticides on locusts and grasshoppers | Commission for Controlling the Desert Locust in the Central Region and Food and Agriculture Organization of the United Nations | 2014 | View URL | |
| FAO locust handbook identification key | FAO Desert Locust Information Service and Food and Agriculture Organization of the United Nations | View URL | ||
| NSF Coupled Natural Human Systems Living with Locusts project summary | Australian Plague Locust Commission, New South Wales Department of Primary Industries, Inner Mongolia Agriculture University, New South Wales Local Land Services, Directorate of Plant Protection, Cheikh Anta Diop University of Dakar, Chinese Academy of Sciences and University of Sydney | 2021 | ||
| USAID Bay Sa Waar Communities for Sustainable Agriculture project summary | United States Agency for International Development, The French Agricultural Research Centre for International Development, Global Locust Initiative, Gaston Berger University, Directorate of Plant Protection, United Nations AGRHYMET Regional Center, Le Centre National de Lutte Antiacridienne, National Desert Locust Control Center, National Network of Agriculture Chambers of Niger, Office de la Protection des Végétaux and The International Committee of the Red Cross,Mira Word Ries | 2021 | ||
| Pest grasshoppers and locusts in Senegal | Global Locust Initiative, United States Agency for International Development and Directorate of Plant Protection | 2020 | ||
| Management of pest grasshoppers and locusts in Mali | Global Locust Initiative, United States Agency for International Development and Directorate of Plant Protection | 2020 | ||
| Community management of pest grasshoppers and locusts in Senegal | Global Locust Initiative, United States Agency for International Development and Directorate of Plant Protection | 2020 | ||
| Locust identification in Niger | Global Locust Initiative, United States Agency for International Development, Directorate of Plant Protection, United Nations AGRHYMET Regional Center, Le Centre National de Lutte Antiacridienne and National Network of Agriculture Chambers of Niger | 2022 | View URL | |
| CIRAD pest locust website | The French Agricultural Research Centre for International Development | View URL | ||
| Locust Literature | The French Agricultural Research Centre for International Development | View URL | ||
| USAID Transboundary Outbreak Pest ETOP bulletins | United States Agency for International Development |
Specimen contributors for this species
Bionomia links specimen records in GBIF to the people who collected and identified them. Each list shows the top 20 for this species. Read more…
Collected by
People who collected specimens of this species in the field.
- Fabian A. Boetzl — 4 specimens collected
- Duarte Frade — 2 specimens collected
- Gonzalo Mucientes Sandoval — 1 specimen collected
- Vijay Barve — 1 specimen collected
- HADDAD Karim — 1 specimen collected
- Biray Pınar — 1 specimen collected
- Sulaiman Inuwa Muhammad — 1 specimen collected
Identified by
People who determined the taxonomic identity of specimens of this species.
- Rob Felix — 16 specimens identified
- Fabian A. Boetzl — 3 specimens identified
- Kaarel Sammet — 2 specimens identified
- Duarte Frade — 1 specimen identified
- HADDAD Karim — 1 specimen identified
- Sulaiman Inuwa Muhammad — 1 specimen identified
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Le Gall M, Touré M, Lecoq M, Marescot L, Cease A, Maiga I (2023) Chapter 4 – Senegalese grasshopper—a major pest of the Sahel. In: Sivanpillai R, Shroder JF (Eds), Biological and Environmental Hazards, Risks, and Disasters (Second Edition). Hazards and Disasters Series. Elsevier, Boston, 77–96. https://doi.org/10.1016/B978-0-12-820509-9.00009-5
- ↑ Diop T (1987) Contribution à l’étude de la dynamique des populations d’acridiens dans la vallée du Sénégal. PhD thesis, Université de Paris VI, Paris, 154 pp.
- ↑ 3.0 3.1 3.2 3.3 3.4 Cheke RA (1990) A migrant pest in the Sahel: the Senegalese grasshopper Oedaleus senegalensis. Philosophical Transactions of the Royal Society B 328: 1251. https://doi.org/10.1098/rstb.1990.0126
- ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 Maiga IH, Lecoq M, Kooyman C (2008) Ecology and management of the Senegalese grasshopper Oedaleus senegalensis (Krauss 1877) (Orthoptera: Acrididae) in West Africa: review and prospects. Annales de la Société entomologique de France 44: 271–288. https://doi.org/10.1080/00379271.2008.10697563
- ↑ Le Gall M, Word ML, Thompson N, Beye A, Cease AJ (2020) Nitrogen fertilizer decreases survival and reproduction of female locusts by increasing plant protein to carbohydrate ratio. Journal of Animal Ecology 89: 2214–2221. https://doi.org/10.1111/1365-2656.13288
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 Kooyman C, Lecoq M (2019) Senegalese grasshopper Oedaleus senegalensis (Krauss, 1877) (Acrididae). In: Lecoq M, Zhang L (Eds) Encyclopedia of pest Orthoptera of the world. China Agricultural University Press, Beijing, China, pp. 170-175.
- ↑ Ritchie JM (1978) Melanism in Oedaleus senegalensis and other oedipodines (Orthoptera: Acrididae). Journal of Natural History 12(2): 153–162.
- ↑ 8.0 8.1 Mestre J (1988) Les acridiens des formations herbeuses d'Afrique de l'Ouest. CIRAD, Montpellier, France, 331 pp.
- ↑ Popov GB (1988) Sahelian grasshoppers. Overseas Development Natural Resources Institute Bulletin 5: 1–87.
- ↑ Popov GB (1985) Résumé des travaux du projet de recherche et de vulgarisation COPR/OCLALAV sur les sauteriaux du Sahel dans la moyenne vallée du Niger. Stations de recherches acridiennes sur le terrain. Séries techniques, N° AGP/DL/TS/25. FAO, Rome, 123 pp.
- ↑ 11.0 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8 COPR (1982) The locust and grasshopper agricultural manual. Centre for Overseas Pest Research, London. 322-325.
- ↑ Cheke RA, Fishpool LD, Forrest GA (1980) Oedaleus senegalensis (Krauss) (Orthoptera: Acrididae: Oedipodinae). An account of the 1977 outbreak in West Africa and notes on eclosion under laboratory conditions. Acrida 9: 107–132.
- ↑ Popov GB (1980) Studies on oviposition, egg development and mortality in Oedaleus senegalensis (Krauss) (Orthoptera: Acridoidea) in the Sahel. Centre for Overseas Pest Research, Miscellaneous Report 53.
- ↑ Langewald J, Ouambama Z, Mamadou A, Peveling R, Stol I, Bateman R, et al. (1999) Comparison of an organophosphate insecticide with a mycoinsecticide for the control of Oedaleus senegalensis (Orthoptera: Acrididae) and other Sahelian grasshoppers at an operational scale. Biocontrol Science and Technology 9(2): 199–214. https://doi.org/10.1080/09583159929785
- ↑ Douro Kpindou OK, Niassy A, Badji K, Kooyman C (2008) Application of mixtures of Metarhizium anisopliae var. acridum and cyhalothrin against the Senegalese grasshopper in Senegal. International Journal of Tropical Insect Science 28: 136–143.
- ↑ 16.0 16.1 Word ML, Hall SJ, Robinson BE, Manneh B, Beye A, Cease AJ (2019) Soil-targeted interventions could alleviate locust and grasshopper pest pressure in West Africa. Science of The Total Environment 663: 632–643. https://doi.org/10.1016/j.scitotenv.2019.01.313
- ↑ Le Gall M, Word ML, Thompson N, Manneh B, Beye A, Cease AJ (2020) Linking land use and the nutritional ecology of herbivores: A case study with the Senegalese locust. Functional Ecology 34(1): 167–181. https://doi.org/10.1111/1365-2435.13466
- ↑ Le Gall M, Word ML, Thompson N, Beye A, Cease AJ (2020) Nitrogen fertilizer decreases survival and reproduction of female locusts by increasing plant protein to carbohydrate ratio. Journal of Animal Ecology 89(10): 2214–2221. https://doi.org/10.1111/1365-2656.13288
- ↑ Bernardi M (1986) Le problème des sauteriaux. In: Compte-Rendu du Séminaire International du Projet CILSS de Lutte Intégrée, Niamey (Niger), 6–13 December 1984, pp. 43–57.