elm sphinx

(Ceratomia amyntor)

elm sphinx
Photo by Luciearl
  Hodges #

7786

 
 
Conservation Status
  IUCN Red List

not listed

 
  NatureServe

N4N5 - Apparently Secure to Secure

SNR - Unranked

 
  Minnesota

not listed

 
           
 
Description
 
 

Elm sphinx is a very large sphinx moth. It occurs in the United States and southern Canada east of the Rocky Mountains. It is common in Minnesota. Larvae feed on the foliage mostly of elms and birches but also of basswood. Reports of larvae feeding on cherry may be erroneous. Adults probably do not feed. They are found in June and July in deciduous woodlands and open areas where its hosts occur.

Adults are 2 to 2 (50 to 60 mm) in length and have a 3¼ to 4½ (82 to 115 mm) wingspan. The forewing length is 1¾ to 11516 (44 to 48 mm). Both sexes are similar in appearance, but females are larger than males. The body is robust. The overall coloration is light and dark shades of brown, grayish-brown, or yellowish-brown.

The upper side of the thorax is densely hairy and brown, with dark brown on the front margin and lateral margins. The antennae are pale and are club-shaped at the tip.

The abdomen is light brown and tapers in the rear to a point. There is a narrow, black, longitudinal stripe in the middle (middorsal), and a broader stripe on each side.

The forewing is long, narrow, and pointed. The outer margin is slightly concave. The upper side is strongly mottled with several shades of light to dark brown. The leading edge (costal margin) is whitish. The basal area is light brown. The median area is light brown on the outer third, dark brown on the inner two thirds, with a small, bar-shaped spot (reniform spot), and a pale patch beyond the reniform spot. The reniform spot is whitish and is not bordered. There are several bold, black dashes along the veins: two long dashes in the median area near the center of the wing, one long dash extending from the lower median area to the subterminal area, one shorter dash in the subterminal area, and two short dashes near the wing tip. From a distance, the overall effect is a dark longitudinal stripe from the wing base to the wingtip. The postmedial (PM) line is represented by three jagged lines with a pale area between them.

The hindwing is mostly dark brown but paler at the base. The PM line is similar in width to the one on the forewing, but it is entirely dark. The fringe on both wings is checkered brown and white.

The caterpillar is up to 3½ (9 cm) in length. It may be brown or green, and it has several pale diagonal lines on each side. There is a pair of spiny horns on both the second and third segments of the thorax. This is the feature that gives the caterpillar the common name four-horned sphinx. There is a line of white, scale-like plates down the middle (middorsal), and the entire body is moderately covered with white-tipped granules.

 
     
 

Size

 
 

Total length: 2 to 2 (50 to 60 mm)

Wingspan: 3¼ to 4½ (82 to 115 mm)

 
     
 

Similar Species

 
     
     
 
Habitat and Hosts
 
 

Deciduous woodlands and open areas

Elm, birch, and basswood

 
     
 
Biology
 
 

Season

 
 

One generation per year: June and July

 
     
 

Behavior

 
 

Larvae feed on the underside of leaves.

 
     
 

Life Cycle

 
 

 

 
     
 

Larva Hosts

 
 

Foliage of mostly elm and birch but also basswood

 
     
 

Adult Food

 
 

Flower nectar

 
     
 
Distribution
 
 

Distribution Map

 

Sources

4, 21, 24, 27, 29, 30, 71, 75, 82, 83.

 
  3/18/2023      
         
 

Occurrence

 
 

 

 
         
 
Taxonomy
 
 

Order

Lepidoptera (butterflies and moths)  
 

Superfamily

Bombycoidea (hawk, sphinx, silk, emperor, and allied moths)  
 

Family

Sphingidae (sphinx moths)  
 

Subfamily

Sphinginae (large sphinx moths)  
 

Tribe

Sphingini  
  Subtribe Sphingina  
 

Genus

Ceratomia  
       
 

Synonyms

 
 

Agrius amyntor

Ceratomia quadricornis

Ceratomia ulmi

 
       
 

Common Names

 
 

elm sphinx

elm sphinx moth

four-horned sphinx (caterpillar)

 

 

 

 

 

 

 

 

Glossary

Reniform spot

A kidney-shaped spot or outline in the lower median area near the PM line on the forewing of many moths.

 

 

 

 

 

 
 
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Luciearl

 
    elm sphinx      
           
 
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Other Videos
 
  Ceratomia amyntor (The elm sphinx)
Bugs Life
 
   
 
About

Apr 23, 2021

Ceratomia amyntor, the elm sphinx or four-horned sphinx, is a North American moth in the family Sphingidae. The species was first described by Carl Geyer in 1835. It has a wingspan of 3 ¹⁄₄-4 ¹⁄₂ inches.

 
  Ceratomia amyntor or Elm Sphinx
Learn with Mr. Weir
 
   
 
About

Aug 23, 2020

This is a really pretty moth found by students at recess. Join the fun by requesting an account for your class so that you can upload images and videos. You can request a free account at http://educationalresource.org/creepycritters

 
  NOW THAT’S A HUGE MOTH! A Elm Sphinx Moth (Ceratomia amyntor) specifically
Kahanu Ermeyas-Tulu
 
   
 
About

Jun 30, 2021

 

 

Camcorder

 
 
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  Luciearl
6/2/2018

Location: Lake Shore, MN

elm sphinx

 
           
 
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Created: 3/18/2023

Last Updated:

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