Loathed by Gardeners, Tomato Hornworms Morph into Magnificent Sphinx Moths

Vegetable gardeners might be inclined to squish tomato and tobacco hornworms, which feast voraciously on tomato, pepper and potato plants and other members of the Solanaceae  family this time of year.  But hey, it’s Pollinator Week, so consider ceding a few fruits or entire plants to these dramatic caterpillars, which later morph into beautiful Sphinx Moths.

Sphinx Moth on Datura, photo by Betsy Betros, via BugGuide.net

Sphinx Moth on Datura, a.k.a. Jimsonweed, photo by Betsy Betros, via BugGuide.net

Loathed by gardeners in its caterpillar stage, the Manduca quinquemaculata, or tomato hornworm, has eight V-shaped marks on each side and a signature horn on the rear.  Manduca sexta, the tobacco hornworm, closely resembles its tomato preferring cousin, but shows seven diagonal white lines on its sides and a curved horn.

Both caterpillars turn into large moths with four- to six-inch wingspans in colors ranging from brown and gold to pink and grey.   They often are mistaken for small hummingbirds when they fly during the day and  hover helicopter style to nectar on flowers, which is why they are also called Hummingbird or Hawk Moths.

Sphinx Moth

C’mon, admit it: she’s adorable. Sphinx Moth, photo courtesy Colorado State University extension office

Moths, the nocturnal brethren of butterflies, are generally under appreciated and yet many are as striking as their celebrated butterfly siblings.  Like butterflies, moths  perform necessary pollination tasks and serve as primary fodder for bats, birds, even small mammals.

The hornworm caterpillars get their name from the signature horns that grace their hind ends.  The “Sphinx Moth” monicker results from the distinct pose the caterpillar assumes when disturbed.  Upon the mildest poke, the creature rears its head in a thoughtful stance, hoisting the upper third of its body in a sphinx-like posture.

The intriguing Sphinx Moth caterpillar on Jimsonweed

Perfectly disguised: the intriguing Sphinx Moth caterpillar blends in on this Datura, a.k.a. Jimsonweed plant.

According to one study, Sphinx Moths are a primary pollinator of Agave plants in the Arizona desert, which in some fashion makes tequila possible.   And yet moths have an unfair reputation as creepy and scary, perhaps because they fly at night, have fuzzy antennae and often exhibit an erratic flight pattern.  Some people even have a fear of moths, called mottephobia.  “Motte” means “moth” in German.

The 1991 thriller The Silence of the Lambs, starring Jodi Foster as tenacious cop Clarice Starling and Anthony Hopkins as cannibalistic serial killer, Hannibal Lecter, didn’t help moths’  reputation.  In the award-winning movie, “Hannibal the Cannibal” places the cocoon of a certain species of hawk moth, the Death’s Head Hawk Moth, in the mouths of  his victims as some sort of sick gesture of transformation. The moths fly around in a creepy, dark basement and evoke a weird terror.

The thriller, Silence of the Lambs, has contributed to moths' creepy reputation.

Quid pro quo, Clarice:The thriller, Silence of the Lambs, has contributed to moths’ creepy reputation.

According to the film trivia website IMDb, the tobacco hornworm moths used in the the film were treated like celebrities by the filmmakers: “They were flown first class to the set (in a special carrier), and had special living quarters (rooms with controlled humidity and heat).”

The movie poster at right featured Jodi Foster with a tobacco hornworm moth photoshopped with a skeleton skull–actually a realistic portrayal of the Death’s Head Hawk Moth, which is generally only found in Africa and southern Europe.

Interestingly, the iconic Death’s Head Hawk Moth tapped for the film is one of few moths that makes a squeaking sound when startled.  Described as a loud, high-pitched squeak, the noise results from air expelling from their proboscis–which might have come in handy during encounters with Hannibal the Cannibal.

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13 thoughts on “Loathed by Gardeners, Tomato Hornworms Morph into Magnificent Sphinx Moths

  1. One of the more intriguing aspects of SILENCE OF THE LAMBS was the scene with the etymologists at New York’s Museum of Natural History. Clever business with the death’s head moth. Thanks for the movie – tobacco hornworm connection. Ken

  2. Did you know gardeners can live in harmony with tomato/tobacco hornworms? Plant a sacrificial tomato plant away from your main crop. Keep the blossoms plucked off and feed with lots of nitrogen fertilizer to grow lots of leaves. Pluck off the caterpillars from your plants you want fruit on and put on the sacrificial one!

    • Thanks for posting this Betsy. We have the “donor” tomato plant this year. I’ve trudged up the hill many a time to give the chubby worms a chance at flying. I just happened to see one last night on the zinnias! Hope others will join.

  3. I just stumbled across your blog when I was trying to identify the difference between a Queen and Monarch butterfly. What a great blog! Wish I had found you earlier. I’m trying to create a butterfly, bird and bee habitat in my backyard. I’m doing my part to help the Monarch population. I have Milkweed, passion flower vines and parsley. Any must have plants to attract butterflies?

    PS I noticed a Zebra longwing butterfly twice this summer in my backyard. I’m thinking this is unusual for San Antonio. Maybe climate change is to blame?

    • Thanks, Stephanie. You definitely want some lantana and pentas. Also, I love Jimsonweed for Sphinx moths. There’s so many possibilities!

      Yes, climate change is bringing some unusual visitors. Zebra longings are not unheard of here, but they’re not uncommon. I used to get them occasionally in Alamo Heights. Good luck!

      MM

  4. Pingback: Another dreaded garden foe |

  5. The passion flowers have a unique structure, which in most cases requires a large bee to effectively pollinate. In the American tropics, wooden beams are mounted very near passionfruit plantings to encourage carpenter bees to nest. The size and structure of flowers of other Passiflora species is optimized for pollination by hummingbirds (especially hermits like Phaethornis), bumble bees, wasps or bats, while yet others are self-pollinating..^,:

  6. ” In the award-winning movie, “Hannibal the Cannibal” places the cocoon of a certain species of hawk moth, the Death’s Head Hawk Moth, in the mouths of his victims as some sort of sick gesture of transformation.”

    It wasn’t Hannibal who did this, it was Buffalo Bill. It symbolized his transformation from man to woman. Get your facts right!

  7. I just found a Tomato Hornworm in my yard. Yesterday it was crawling around and today it looked like it was darkening in color and not nearly the energy it had the day before. I would like to try and save it so it can become this beautiful moth. Any suggestions?

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