Melanoplus differentialis

Adults distinguished by black chevron markings on hind femur and male cercus shape. Nymphs identified by combination of: brown compound eyes with light tan spots and no transverse band; pale yellow stripe at top of pronotal lobe continuous with genal band; black stripe or chevrons on hind femur; light green or gray hind tibia. Differs from Melanoplus femurrubrum (redlegged grasshopper) by lacking bright red hind tibia and having yellow rather than bright yellow underside. Differs from Melanoplus bivittatus (twostriped grasshopper) by hind femur pattern (chevrons vs. stripes) and male cercus shape.

Large yellow grasshopper with distinctive black markings. Adults typically show bright yellow ground color with black patterning. Diagnostic features include chevron-like black markings on the hind femur and characteristic shape of the male cercus. Some individuals exhibit melanism (entirely black coloration) through nymphal and adult stages. Nymphs display compound eyes brown with light tan spots (no transverse dark band), green/yellow/tan head front often with dark spots, pale yellow horizontal stripe at top of pronotal lobe, and black stripe on hind femur in early instars developing into chevrons in later instars. Hind tibia light green to gray.

Originally restricted to tall herbaceous vegetation in wet meadows, swales, and creek bottomlands. Following agricultural development, expanded into weedy vegetation of crop borders, roadsides, and field reversions. Large populations develop in extensive cropland areas, particularly between the Rocky Mountains and Mississippi River. Favors areas with abundant forbs, especially members of Compositae.

Widely distributed in North America from northern Mexico through the central United States to southern Ontario, Canada. Core range lies between the Rocky Mountains and Mississippi River; populations east and west of these landmarks are spotty and discontinuous. Present in Colorado, Illinois, Vermont, and throughout the central plains and Midwest.

Eggs begin hatching in late spring, approximately two weeks after Melanoplus sanguinipes and three weeks after Melanoplus bivittatus. Nymphal development requires about 32 days under warm conditions. Adults present from mid-summer through fall. Oviposition occurs in late summer and early fall. One generation annually.

Polyphagous, feeding on both grasses and forbs. Crop content analysis shows greater consumption of forbs than grasses. Laboratory studies demonstrate faster development, larger size, and higher fecundity on forb diets compared to grass diets. Known host plants include giant ragweed, blood ragweed, common sunflower, prickly lettuce, soybean, wheat, and various crop plants. Shows preference for wilted or damaged sunflower, likely due to increased sugars and amino acids in stressed tissues. Does not perform well on alfalfa as sole diet.

Egg stage: eggs deposited in curved pods 1.5 inches long, 0.25 inch diameter, containing 45-194 olive-colored eggs 4.4-5.1 mm long. Embryonic development begins at deposition, reaches 54% development by fall, diapauses through winter, resumes in spring. Hatching concentrated in two-week period in late spring. Nymphal stage: five to six instars, development synchronized, adults emerge over short period. Adult stage: pre-oviposition feeding period, mating pairs form in morning and may remain coupled 20-24 hours, females oviposit in sod or rank weeds. One generation annually.

Highly mobile in both nymphal and adult stages. Third instar and older nymphs move as cohesive bands into fields by crawling and hopping. Adults display strong flight, moving upwind in short flights of 10-100 yards toward green food, beginning around 9 a.m. and peaking at 81°F. Flight used for escape from temperatures above 86°F. Documented migration of 130 miles by successive short flights in 1939; individuals recovered 20 miles from release point within two days. Daily activity: inactive at night, resting high on vegetation; nymphs descend to bask when temperatures reach 65°F; feeding begins at 68°F, general feeding at 75°F; seek shade when soil surface reaches 112°F. Under cloudy conditions, nymphs remain inactive regardless of temperature.

Herbivore consuming significant plant biomass; during outbreaks, populations reach densities capable of regionally altering vegetation composition. Serves as prey for birds, mammals, and other insectivores. High biotic potential allows rapid population increases under favorable warm, dry conditions.

Major agricultural pest causing severe damage to small grains, corn, alfalfa, soybeans, cotton, vegetables, and deciduous fruit trees. Dense swarms destroy young cornfields in 3-4 days. Outbreaks historically documented since 1930s, with severe Missouri outbreak 1936-1937. Subject to grasshopper management and control programs. Used as model organism in cytogenetic and embryological research.

• Melanoplus femurrubrumSimilar size and general appearance; distinguished by bright red hind tibia (vs. green/gray in M. differentialis), bright yellow underside, and different male cercus shape
• Melanoplus bivittatusOverlapping range and habitat; distinguished by two pale stripes running length of body, striped rather than chevron pattern on hind femur, and different male cercus shape
• Melanoplus sanguinipesEarlier hatching and different habitat preferences; distinguished by more slender body, different hind femur markings, and different male cercus shape

• pest
• agricultural
• migratory
• polyphagous
• phase polymorphism
• univoltine

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Differential Grasshopper
• List of Species Fact Sheets| Grasshoppers of Wyoming and the West
• Grasshoppers of Colorado
• Redlegged Grasshopper
• Grasshoppers of Colorado
• Species Records and Accounts
• Synaptonemal complex karyotyping in Melanoplus Differentialis
• Phase Polymorphism in the Grasshopper Melanoplus differentialis
• Quantitative Study of Distribution of Sulfhydryl Groups in the Developing Grasshopper (Melanoplus differentialis) Embryo
• Changes in Distribution of Sulfur-Containing Amino Acids in Developing Grasshopper Egg (Melanoplus differentialis)
• Changes in the Distribution of Phosphorus in the Developing Grasshopper (Melanoplus differentialis) Embryo
• Life cycle, sex differentiation, and testis development in Melanoplus differentialis (Acrididae, Orthoptera)
• NITROGEN CONTENT AND DISTRIBUTION IN EGGS OF MELANOPLUS DIFFERENTIALIS DURING EMBRYONIC DEVELOPMENT