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Eastern Lubber Grasshopper, Romalea microptera (Beauvois) (= guttata (Houttuyn)) (Insecta: Orthoptera: Acrididae)1
C. W. Scherer and J. L. Capinera2
Introduction
Periodically, grasshoppers have been of economic importance in Florida. A few species sometimes occur in large enough numbers to cause serious damage to citrus, vegetable crops and landscape ornamentals. One of the species most commonly causing damage is the eastern lubber grasshopper, Romalea microptera. Most authorities give it this scientific name, but sometimes it is known as Romalea guttata (Houttuyn).
Distribution
The eastern lubber grasshopper is limited to the southeastern and south central portion of the United States ( Figure 1 ). The northern boundary is central North Carolina west through southern Tennessee, Georgia, Alabama, Mississippi, Louisiana, Arkansas, to Texas. It occurs throughout Florida.
CREDITS: J. L. Capinera, University of Florida
Figure 1. Distribution of Romalea microptera, eastern lubber grasshopper. Description
The lubber is surely the most distinctive grasshopper species in the southeastern United States. It is well known both for its size and its unique coloration. The wings offer little help with mobility for they are rarely more than half the length of the abdomen. This species is incapable of flight and can jump only short distances. Mostly the lubber is quite clumsy and slow in movement and travels by walking and crawling feebly over the substrate.Nymphs
The immature eastern lubber grasshopper differs dramatically in appearance from the adults. Nymphs (immature grasshoppers, Figure 2 ) typically are completely black with one or more distinctive yellow, orange, or red stripes. The front legs and sides of the head are often red. Sometimes the nymph is brownish red, but also displays the colorful stripes ( Figure 3 ).
CREDITS: J. L. Capinera, University of Florida
Figure 2. Young nymph of eastern lubber grasshopper, Romalea microptera.
CREDITS: J. L. Capinera, University of Florida
Figure 3. Older nymph of eastern lubber grasshopper, Romalea microptera. Adults
Adult males and females are usually 6.0 and 8.0 cm. long, respectively. The body is quite robust while the legs remain relatively slender. The general color of adults is dull yellow with varying degrees of black spots and markings ( Figure 4 ). The front pair of wings (tegmina) are yellow with numerous scattered black dots, while the hind wings when exposed reveal a bright red/rose coloration with a black border.The color of adult lubbers also varies throughout most of the insect's range ( Figure 5 ). One phase is nearly entirely black with a few marks of yellowish tawny ( Figure 6 ). The adults of this phase seem to resemble the nymph. However, the different phases are indeed the same species.
CREDITS: J. L. Capinera, University of Florida
Figure 4. Adult eastern lubber grasshopper, Romalea microptera, light color phase.
CREDITS: J. L. Capinera, University of Florida
Figure 5. Adult eastern lubber grasshopper, Romalea microptera, intermediate color phase.
CREDITS: J. L. Capinera, University of Florida
Figure 6. Adult eastern lubber grasshopper, Romalea microptera, dark color phase. Life Cycle
Adults of Romalea microptera exist nearly throughout the year in Florida with their numbers dwindling during the fall and winter period. They have one generation per year, with eggs beginning to hatch in February in South Florida while the rest of the state usually doesn't see this species until March. Eastern lubbers, like all grasshoppers, grow through successive stages after molting. These stages (instars) are referred to as nymphs. Lubbers have a total of five instars before molting into the adult stage. The length of these instars vary slightly but average 15 to 20 days each. The highest number of adults can be observed during the months of July and August.Females will begin laying eggs during the summer months. After mating, females use the tip of the abdomen to dig a small hole into a suitable patch of soil. Usually at a depth of about two inches, she will deposit up to 50 eggs contained within a light foamy froth. Each female will lay from one to three egg masses. These eggs will remain in the soil through late fall and winter and then begin hatching in March. The young grasshoppers crawl up out of the soil upon hatching and seem to congregate near suitable food sources. Lubbers are often found in damp or wet habitats, but seek drier sites for egg-laying.
Populations cycle up and down, possibly due to the action of parasites. The tachinid fly Anisia serotina (Reinhard) attains high levels of parasitism, sometimes 60-90%.
Habitat
Eastern lubber grasshoppers seem to prefer open pine-woods, weedy fields and weedy vegetation along roadsides. Occasionally, on rural highways in the central portion of the state, enough flattened lubber grasshoppers will accumulate on the road to cause a minor slick!The accumulation of weedy plant species along drainage ditches within citrus groves and vegetable fields will sometimes attract lubbers, which in turn end up feeding on the cultivated crops as well. Lubbers may often invade residential areas and feast on certain ornamental plants, especially amaryllis and related flowers.
Defensive Characteristics
Eastern lubber grasshoppers possess a variety of abilities to defend themselves. Their bright color pattern is a warning to predators that the lubber contains toxic substances. Indeed, there are several records attributing the demise of individual birds to failure to exercise caution when selecting prey items. Also small mammals such as opossums have been known to vomit violently after ingesting a lubber, and to remain ill for several hours. However, shrikes are reported to catch and kill lubbers.If the red, yellow, and black coloration fails to keep a predator at bay, then the lubber may secrete a foamy spray from the thoracic region (the portion of the body where the legs and wings are attached.) This spray consists of a number of compounds, some of which, are irritants. This bubbly froth is accompanied by a relatively loud, frightful hissing sound. The insect contracts the abdomen to force air out of the spiracles along with the defensive secretion. The sound is produced as the spray is being forced out of these tiny holes in the thorax called spiracles. Eastern lubbers, like most all grasshoppers, can also regurgitate recently consumed plant material. This regurgitant is mostly liquid and has a dark brown color. This is commonly referred to as 'tobacco spit.' The tobacco spit is partially digested food material along with some semi-toxic compounds from the insect's crop region. This substance can easily stain clothing.
Management of Lubbers
The size of the eastern lubber grasshopper is a little misleading when one considers they require far less food material than most of the more injurious species of grasshoppers that are only one-third as large or smaller.Grasshopper abundance can be regulated through management of the vegetation. If you deprive grasshoppers of their favored food, often they will leave or perish. Keeping the vegetation mowed is very helpful, as short vegetation does not often support grasshoppers
Lubber grasshoppers will often develop initially in moist areas around ponds and irrigation ditches, then later migrate to homes, yards, and crops. Rather than waiting for the grasshoppers to come to you, it is often best to take the battle to them. So check potential breeding or feeding sites for signs of grasshoppers. The young grasshoppers remain clustered in groups, but as they get older they are more likely to be solitary. If you cannot control them through mowing, try hand-picking. You can throw them into a bucket of soapy water or a trash bag to kill them.
If there are too many to control by hand-picking, insecticides can be applied. Lubber grasshoppers are not easy to kill, even with insecticides, once they become large. Among the insecticides that will kill lubber grasshoppers are carbaryl, bifenthrin, cyhalothrin, permethrin, and esfenvalerate (note: these are the technical names, which appear in the 'ingredients' section on the label). You likely will have to apply the insecticide directly to the insects; the small amount of insecticide residue remaining on sprayed plants may not be adequate to kill the grasshoppers.
If insecticides are to be used, be sure to apply them according to the directions on the label of the container. Especially if insecticides are applied to food crops or near water, it is important to heed the directions. Most of the insecticides listed above are toxic to fish.
For specific recommendations, refer to the Florida Insect Management Guide:
Grasshoppers are much easier to control when they are nymphs. As they mature, and grow larger, higher rates of toxicants must be applied for effective control.
- Insect Management Guide for Citrus (http://edis.ifas.ufl.edu/cg005 )
- Insect Management Guide for Foliage and Woody Ornamentals (http://edis.ifas.ufl.edu/IG012 )
- Insect Management Guide for Vegetables (http://edis.ifas.ufl.edu/TOPIC_IG:Vegetables)
CREDITS: J. L. Capinera, University of Florida
Figure 7. Clustered nymphs. Selected References
Blatchley WS. 1920. Orthoptera of Northeastern America. Nature Publishing Company. Indianapolis, Indiana. p. 304-307.Capinera JL, Scherer CW, Squitier JM. (September 1999). Grasshoppers of Florida. http://entnemdept.ifas.ufl.edu/ghopper/ghopper.html (September 1999).
Fasulo TR, Brooks RF. (1998). Grasshopper, katydid and cricket pests of citrus. EDIS. http://edis.ifas.ufl.edu/CH056 (June 2004).
Griffiths JT, Thompson WL. 1952. Grasshoppers in citrus groves. University of Florida Agricultural Experiment Station Bulletin no. 496.
Helfer JR. 1953. How to Know the Grasshoppers, Cockroaches and Their Allies. WM.C. Brown Company Publishers. Dubuque, Iowa. p. 100-101.
Kuitert LC, Connin RV. 1953. Grasshoppers and their control. University of Florida Agricultural Experiment Station Bulletin no. 516.
Lamb MA, Otto DJ Whitman DW. 1999. Parasitism of eastern lubber grasshopper by Anisia serotina (Diptera: Tachinidae) in Florida. Florida Entomologist 82: 365-371.
Mizell RF, Fasulo TR, Short DE. (2002). WoodyBug: pest and beneficial arthropods of southeastern U.S. woody ornamentals . UF/IFAS. CD-ROM. Sw 119.
Rehn JAG, Grant Jr HJ. 1961. A Monograph of the Orthoptera of North America (North of Mexico). Monographs of the Academy of Natural Sciences of Philadelphia. No. 12. Vol. 1. p.231-240. Wickersham Printing Company. Lancaster, Pennsylvania.
Short DE, Mizell RF, Fasulo TR. (1998). Woodybug: A knowledgebase of pest and beneficial arthropods of Florida woody ornamentals. SW 119. CD-ROM.
Whitman DW, Jones CG, Blum MS. 1992. Defensive secretion in lubber grasshoppers (Orthoptera: Romalidae): influence of age, sex, diet, and discharge frequency. Annals of the Entomological Society of America 85: 96-102.
Wilkerson JL, Webb SE, Capinera JL, Fasulo TR. (2005). Vegetable Pests II: Acari - Hemiptera - Orthoptera - Thysanoptera . University of Florida/IFAS. CD-ROM. SW 181.
Footnotes
1. This document is EENY-006 (IN132), one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: October, 1996. Revised: February, 2008. This document is also available as a Featured Creature at http://creatures.ifas.ufl.edu/. Please visit the EDIS Website at http://edis.ifas.ufl.edu.2. C. W. Scherer, graduate assistant, and J. L. Capinera, professor/department chairman, Entomology and Nematology Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other extension publications, contact your county Cooperative Extension service.
U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
Copyright Information
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