A “Texas earthworm,” under the theory that “everything’s bigger in Texas,” is a rattlesnake. The name and image of a “Texas earthworm” has been put on T-shirts since at least 2009.
 
   
Famous Quotes and Quotations
Funny Texas Quotes
Texas Earthworm
(this was on a sign that depicted a rattlesnake)
 
14 October 1954, San Antonio (TX)

, “Around the Plaza” by Renwicke Cary, pg. 25, col. 1:
Leonard Smith,  the retired infantry colonel, passing along a bit of foolishness he received in a note from his wife, Betty, who’s visiting Little Rock. To wit: “Ft. Worth keeps no python. It ain’t no snake a-tall. It’s just a Texas earthworm that’s been taking Hadacol.”
     
TCE Lounge
Thread: A REAL SNAKE IN THE GRASS
Charger68
08-24-2008, 07:03 PM
Texas earthworm and having that snake so far from the guy creates the illusion of a huge snake, it’s not nine feet and a hundred pounds!!! But if ya killit, eat it, rattlesnake is some good eating!! Tastes like RATTLESNAKE!!!!
     
Google Books
AKC Gazette
American Kennel Club, Inc.
Volume 126
2009
Pg. 47:
Avoiding the Texas Earthworm
In south Texas, it is not uncommon to I see a T-shirt picturing a rattlesnake, coiled to strike, captioned TEXAS EARTHWORM. At first glance one may find it amusing, yet it carries a serious and sometimes deadly message. A member of the pit viper family, there are approximately 30 species and numerous subspecies of the rattlesnake.