UF/IFAS Okeechobee County Extension Service

458 Highway 98 North

Okeechobee, FL 34972-2578

Phone: (863) 763-6469

E- mail: indianco@ufl.edu 

October 6, 2005

Feature Article - for release the week of October 9, 2005

Dan Culbert - Extension Horticulture Agent

Beware of Shooting Walking Sticks

Guess I’m lucky.  A few years ago I was training some Master Gardeners and encountered a Wheel-bug on a flowering shrub.  The pretty colors and unusual shape were intriguing.   I allowed it to walk on my fingers and showed the volunteers up close what they looked like, and then retuned it to the shrub.   Later on, I discovered that this predator insect can pack a very painful sting.  I found that to be a close call.

Beware -  Wheel bugs can sting! Photo by James Castner, UF/IFAS

This past week I uncovered another insect – a walkingstick - hanging out in my Florida Yard.  I carefully picked them up (there were two), and moved them off the branch I was trimming.  I’ve now found out that this Florida critter also has some hidden danger – it can forcefully shoot a caustic juice at attacking creatures that can result in very painful eye stings.  So maybe it’s time to review what we know about walkingsticks – another interesting creature in our Florida Yard.

Walkingsticks are close relatives to grasshoppers, crickets, palmetto bugs and preying mantids. In Florida, the local kind of walkingstick is known as the two-striped walking stick, Anisomorpha buprestoides.  This featured insect has been reported throughout Florida and around the Gulf Coastal Plain west to Texas.  Other names applied to these stick insects in general include devil's riding horse, prairie alligator, stick bug, witch's horse, devil's darning needle, scorpion, and the musk mare.

Walkingsticks are among the longest insects in the world – one exotic species has been measured at 22 inches!   However, the local two-striped females average only 2½ inches in length, while the males are smaller and more slender, averaging 1½ inches.  Generally these insects are dark brown with two long yellowish stripes running down the length of their back.  However, there is a strikingly distinct black and white color form that is found only in the area of the Ocala National Forest.  Check the color quickly if you are collecting them, as they discolor upon death.

A second species of walking sticks occur in the southeastern U.S., but has not been seen in   Florida. It is smaller in size and lighter in color, and lacks the stripes. Other species of walkingsticks occur in the US and across the globe.  Some are even used as pets!

Some years the number of these insects is greater than in others.  Duval County Horticulture Agent Terry DelValle reported that in the fall of 2003, the populations of this insect were higher than normal in Jacksonville.  An entomologist (C. Tozier) also reported a large local population of these insects north of Ocala just a few hours before Hurricane Charley stormed through last summer.

Typically, they do not eat so many leaves with their chewing mouthparts that they need to be controlled; pesticide use against these insects is not suggested.  These insects feed on leaves of trees and shrubs with some of their favorites listed as crape myrtles, roses, oaks, rosemary, lyonia and Ligustrum shrubs.  

Since these insects show gradual or incomplete metamorphosis, they slowly get larger through the growing season, and are most likely to be seen in the late summer and fall.  Often the larger female can be seen with a smaller one attached (male).  The male will mate and hold on to the female for long periods of time – it is thought that this is a way for the male to be certain that other males will not mate with that female.  Eggs are usually laid in the fall on the ground in a pit and covered with sand.

Our local walkingstick has a couple of defensive mechanism that Floridians should know about.  Their first line of defense is to look like a dead stick, and so are often overlooked.  In some cases they vibrate, as if the wind was blowing. 

But, if they are physically disturbed, they secrete a foul smelling milky fluid from two pores of the thorax. They also have the ability to force a stream from their body as far as a foot in distance.  Researchers have found that this secretion contains substances that can produce a powerful burning sensation if it gets into the eyes.

For those that have had such an encounter, (see stories below!) the recommended treatment is to wash the eye with large amounts of water and take over-the-counter analgesics for pain. For severe symptoms, a trip to the eye doctor may be necessary.  A individuals in Texas was reported to have vision problems for up to five days. A report from Brevard County last month says that another person was sprayed in the eyes by this insect. 

An urban legend has been circulating that an exotic walkingstick from Belize (or sometimes Brazil) that was found in Texas and is spreading east.  According to UF Entomologist Tom Fasulo, while there are plenty of Central and South American walkingsticks, they are not in Texas - at least not yet. This story is a hoax - however, it is based upon some truth.  While there is no known invasion of alien poison-spitting walkingsticks, our local native two-striped walkingstick can spray a secretion that can cause pain and impair vision.

So, if you see a live “dead” stick in your Florida Yard, observe it if you wish, but don’t “bug” it.  I’ve placed more information on our Okeechobee web page, http://okeechobee.ifas.ufl.edu.  If you need additional information on walkingsticks, please email us at okeechobee@ifas.ufl.edu or call us at 863-763-6469.  Local residents can stop by our office at 458 Hwy 98 North in Okeechobee, and visit our Okeechobee County Master Gardeners .

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Trade names, where used, are given for the purpose of providing specific information. They do not constitute an endorsement or guarantee of products named, nor does it imply criticism of products not named. The Florida Cooperative Extension Service - Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research, educational information, and other services to individuals and institutions that function without regard to race, color, sex, age, handicap, or national origin.  Florida Cooperative Extension Service / IFAS / University of Florida.  Millie Ferrer-Chancy, Interim Dean Last update: 09/14/2011 .  This page is maintained by Dan Culbert 

references

Branscome, Deanna.  Chapter 33 - Longest. University of Florida Book of Insect Records. Gainesville: Department of Entomology & Nematology, April 17, 1998. http://entnemdept.ufl.edu/walker/ufbir/chapters/chapter_33.shtml 

DelValle, Terry B.  "Twostriped Walking Stick." In: A New Leaf (Duval County Extension Newsletter) Vol. 4, issue 6, November/December 2003.

Fasulo,Thomas R. - "Arthropod Hoaxes" Pest Alert. Gainesville: UF/IFAS Extension Service, 12/04/03. http://entnemdept.ifas.ufl.edu/pestalert/hoaxes.htm 

Greater Los Angeles Zoo Association (GLAZA).  Vietnamese Walkingstick, 2008. [shows a video of this insect !]  http://lazoo.org/animals/invertebrates/vietwalkingstick/ 

Peterson, Patrick "Ouch! The sting of growth - Insects use a painful defense against Brevard residents" Melbourne: Florida Today  September 17, 2005  http://www.floridatoday.com/

Thomas,  Michael C. The Twostriped Walkingstick, Anisomorpha buprestoides (Entomology Circular No. 408)  Gainesville: FDACS/DPI, Sept/Oct 2001. http://edis.ifas.ufl.edu/IN590 and  http://www.freshfromflorida.com/pi/enpp/ento/entcirc/ent408.pdf 

Thomas, M.C. and Fasulo, T.R.  Twostriped walkingstick (Featured Creatures). EENY-314.  Gainesville: UF/IFAS Extension Service, November 2003 http://entnemdept.ifas.ufl.edu/creatures/misc/walkingstick.htm 

Tozier, Christopher.  Behavioral activity of Anisomorpha buprestoides possibly associated with Hurricane Charley.  Florida Entomologist.  88 (1), March 2005. http://www.fcla.edu/FlaEnt/fe88p106.pdf 

Questions/ Answers and stories of encounters with Walkingsticks