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Conocephalus saltator (Saussure)

Longhorned Grasshopper
Hosts Distribution Damage Biology Behavior Management Reference

Authors

Jayma L. Martin Kessing, Educational Specialist

Ronald F.L. Mau, Extension Entomologist

Department of Entomology

Honolulu, Hawaii

HOSTS

Host plants of the longhorned grasshopper include bean blossoms, coffee, corn, guava, lantana, leaves of young sugarcane, honohono grass, morning glory blossoms, potato, rice pollen, and several ornamentals. Although not a host for feeding, pineapple fruits are sometimes damaged because this grasshopper lays their eggs in the flowers of the young fruit.

DISTRIBUTION

This grasshopper is widespread throughout tropical America and also found on Midway and Hawaii. It was found in Honolulu in 1892 (Brunner, 1895). Because it lays its eggs beneath the sheaths of sugar cane it could be easily distributed on "seed" cane, and this probably accounts for its present on all major islands in Hawaii (Swezey, 1905).

DAMAGE

This insect is primarily considered beneficial because most of its diet consists of other insects. Occasionally it will feed on blossoms and foliage where it may do some damage to the host plant. Minimal damage may occur during the deposition of eggs between leaf sheaths and a bulge may occur on the leaf sheath.

BIOLOGY

The longhorned grasshopper develops from egg to adult in 2-1/2 to 3-1/2 months.

EGGS

Eggs are deposited into plant tissue or beneath leaf sheaths, side by side, in groups of two to 15. They are 1/5 inch long and about 1/25 inch in greatest diameter. They are blunt at one end and pointed at the other (Swezey, 1905) and greenish in color. Eggs hatch in 14 to 35 days.

NYMPHS

The nymphal grasshoppers are similar in appearance to the adults, but are sexually undeveloped. They are green with a brown, pale-edged stripe running down their back (Swezey, 1905). Each nymphal stage, or instar, is separated by a molt. Nymphs molt six times before reaching adulthood. The first molt occurs after 6 to 11 days, the second molt after a 7 to 23 day interval, the third after a 9 to 12 day interval, the fourth after a 8 day interval, the fifth after a 9 day interval and the last molt (from which the adult emerges) occurs after a 20 day interval. The total nymphal stage lasts from 59 to 108 days depending on temperature and host.

The ovipositor, which allows the female to deposit eggs into plant tissues, first appears as a projection at the end of the body during the second nymphal stage and continues to increase in size until sexual maturity is reached at adulthood.

ADULTS

Like most other grasshoppers belonging to the Tettigoniidae family, the most characteristic feature is the long antennae that extend from the head back past the tail of the grasshopper (total length 1-4/5 to 2-2/5 inch). The adult longhorned grasshopper is bright green with a reddish brown stripe running from the front of the face down the length of the body. Sometimes white or yellowish stripes are on either side of the main reddish-brown stripe. Eyes are brown, mandibles (large teeth-like appendages on the face) are black, and the face is spotted with brownish dots. Antennae are green with brown rings and entirely brown at the tips. The length of the body varies between 3/5 to 4/5 inch and females have a brown ovipositor that extends out about 2/5 inch.

BEHAVIOR

The noise produced by the longhorned grasshopper is a rapid chirping similar to the sound of a small electric motor whose brushes squeak as it turns (Zimmerman, 1948).

Most grasshoppers are primarily grass and foliage feeders. However, this grasshopper often feeds on smaller insects such as sugar cane leafhoppers and aphids, and is only occasionally known to feed on young sugar cane and the blossoms of Canna, lantana and other plants.

MANAGEMENT

NON-CHEMICAL CONTROL

Several natural enemies of the longhorned grasshopper are present in Hawaii. Parasitic wasps include Isodontia harrisi (Fernald), which attacks nymphs and adults, and two egg parasites, Centrodora xiphidii (Perkins) and Bracnistella lutea (Fullaway) (Zimmerman, 1948). When present in the field, the egg parasites are very effective in decreasing longhorned grasshopper populations, perhaps because their developmental period (20 to 31 days) is about one-third that of its host (Swezey, 1905).

CHEMICAL CONTROL

No information available.

REFERENCES

Swezey, O. H. 1905. Orthoptera. Bulletin of the Experiment Station of the Hawaiian Sugar Planter's Association, Division of Entomology. 1(7): 211-223.

Zimmerman, E. C. 1948. Conocephalus saltator (Saussure) pp. 121-122. In: Insects of Hawaii, A Manual of the Insects of the Hawaiian Islands, including an Enumeration of the Species and Notes on their Origin, Distribution, Hosts, Parasites, etc. Volume 2: Apterygota to Thysanoptera. University of Hawaii Press, Honolulu. 475 pages.

 

JUL/1992.

 

C-SALTAT

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