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Endelomyia aethiops and Allantus cinctus

Roseslug sawfly damage. Photo: Tawny Simisky, UMass Extension.
Scientific Name: 
Endelomyia aethiops and Allantus cinctus
Common Name: 
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Rose (Rosa spp.)
Insect Description: 

The term roseslug or roseslugs refers to a couple different species of sawfly caterpillars found on rose. The roseslug (Endelomyia aethiops) may be found on the same plants as the curled rose sawfly (Allantus cinctus). The roseslug, E. aethiops, is found in British Columbia as well as the United States, and is thought to be a native species The roseslug was first identified as a pest in Cambridge, MA in gardens in 1831 (Chittenden, 1908). According to Chittenden, 1908, "By 1840 it had become so great a nuisance that a premium of $100 was offered for the most successful method of destroying it (Harris)". Rose species are their only hosts, and females lay eggs in individual pockets on the edges of leaves. This is done with the female's ovipositor (egg laying device) which cuts a pocket between the leaf surfaces into which the egg is inserted. Hatching occurs 10-14 days after eggs are laid. Newly hatched larvae begin to feed by skeletonizing the upper surfaces of leaves. The roseslug larvae (caterpillars) are approximately 1/2 inch long when mature, and complete their skeletonization feeding at that time, after approximately 5-6 weeks of feeding. During the day, larvae rest on the undersides of leaves. Once ready to pupate, they leave the plant and enter the soil to create a cell within which they overwinter. This species of roseslug's larvae may all be done feeding and in the soil by approximately July. They remain in their winter cells until the following spring, at which time pupation occurs. A single generation of E. aethiops occurs per year. Adults are dark in color (deep, shiny black) and wasp-like with four smokey colored wings. Adult females are approximately 1/5 inch long, with males slightly smaller.

The curled rose sawfly, Allantus cinctus, is approximately 0.75 inch long at the time the caterpillar is fully mature. This species is likely an accidental introduction from Europe, first viewed as a pest near Boston, MA in 1887 (Chittenden, 1908). Because their caterpillars are larger than those of the roseslug, it only takes a few of them to seriously damage plants. The curled rose sawfly does not often occur in large populations, yet for the aforementioned reason they can still be significant pests. Caterpillars of this species not only injure plants by feeding on their leaves, but they also bore into the pith of twigs, which can kill stems and act as an area for fungal pathogens to become introduced. Caterpillars of this species will skeletonize the leaves and are eventually capable of eating the entire leaf except the main vein. Boring into the pith of the twig, especially pruned twigs, occurs when the insect is ready to pupate. It is possible that two generations of the curled rose sawfly can occur per year, and in some locations, three may occur. Caterpillars of this species are green on their backs, with abdomens marked with white spots. The head of the caterpillar is yellow in color with a dark brownish stripe down the middle, and with black eye spots. Caterpillars may be found coiled when at rest. Adults are approximately 3/8 inch long, with nearly transparent wings and a shining black abdomen with a wide band in the middle. Adult emergence occurs some time in May. Eggs are laid singly on leaf undersides in groups of 3-7. Historically, adults had also been observed in again in Boston, MA in July (Chittenden, 1908). Other species of sawflies with similar habits may be found on similar host plants in different geographic locations.

Damage to Host: 

These slug-like sawflies skeletonize the upper leaf surface, especially on rambler rose. Leaves may be so damaged, that entire shrubs look as if they have been scorched by fire. After heavy feeding, the leaves may drop from the host plant. Endelomyia aethiops caterpillars skeletonize the upper leaf surface of their host plants. Allantus cinctus is an introduced species whose caterpillars are slightly larger, and as such it only takes a few to seriously damage their host plants. Curled rose sawfly caterpillars not only injure plants by feeding on their leaves, but they also bore into the pith of twigs, which can kill stems and act as an area for fungal pathogens to become introduced. Curled rose sawfly caterpillars skeletonize the leaves initially, and eventually can eat the entire leaf except for major veins.


Monitor for feeding caterpillars by the end of May through June. Caterpillars and their feeding damage may be seen on the upper surfaces of leaves. Look for dead stems caused by Allantus cinctus boring into the pith of twigs. Allantus cinctus caterpillars, a second generation, may again be present in August. 

Cultural Management: 

Small numbers of roseslugs on a single shrub can be removed by hand and destroyed. Syringing the plants with a strong stream of water, such as from a garden hose, every day or two also dislodges the roseslugs. This has been noted as an effective means of managing these insects by Chittenden, 1908. Chittenden notes that Dr. L. O. Howard was successful in ridding infested plants of these insects this way. Tilling soil between rose plants in the late summer or early fall is also suggested as a means of managing this insect, to disrupt the overwintering cells of the mature caterpillars preparing to pupate next season. Prune out and destroy stems within which Allantus cinctus may be preparing to pupate.

Natural Enemies & Biological Control: 

Not much is known about the natural enemies of roseslugs. Chittenden, 1908, reared a tachinid fly from Allantus cinctus that was collected from larvae sampled in Allegheny, PA, in 1904. At the time, the species was determined to be Tachina rustica. Chittenden, 1908, also notes that in Europe, an ichneumonid fly, Cryptus emphytorum, was also known to be parasitic upon Allantus cinctus.

Chemical Management: 

Acephate (NL)

Azadirachtin (larvae) (NL)

Carbaryl (L)

Cyfluthrin (larvae) (NL)

Deltamethrin (larvae) (L)

Dinotefuran (larvae) (NL)

Emamectin benzoate (L)

Flonicamid+cyclaniliprole (N)

Gamma-cyhalothrin (L)

Horticultural oil (larvae) (L)

Imidacloprid (larvae) (L)

Insecticidal soap (larvae) (NL)

Lambda-cyhalothrin (L)

Pyrethrin+sulfur (larvae) (NL)

Spinetoram+sulfoxaflor (larvae) (N)

Spinosad (larvae) (NL)


Active ingredients that may be applied systemically include: acephate (injection), azadirachtin (injection, soil drench), dinotefuran (soil drench), emamectin benzoate (injection), and imidacloprid (soil drench).

Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.

Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: .