Moths of North Carolina
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42 NC Records

Saucrobotys futilalis (Lederer, 1863) - Dogbane Saucrobotys Moth


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Taxonomy
Superfamily: Pyraloidea Family: CrambidaeSubfamily: PyraustinaeTribe: PyraustiniP3 Number: 801407.00 MONA Number: 4936.00
Comments: Munroe (1976) recognized two subspecies, with North Carolina specimens belonging to Saucrobotys f. futilalis
Identification
Field Guide Descriptions: Beadle and Leckie (2012)Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Munroe (1976)Technical Description, Immature Stages: Allyson (1981)                                                                                 
Adult Markings: In this species the head, thorax, antennae, and forewing ground color are concolorous and vary from brownish fuscous to orangish brown. The transverse antemedial and postmedial lines are both dentate and dark brown, with the postmedial outwardly curved on the costal half, then slanting obliquely inward to the inner margin. The hindwing is whitish buff and sometimes narrowly infuscated at the outer margin. The postmedial line is faint and often not evident.
Wingspan: 14-16 mm (Powell and Opler, 2009).
Adult Structural Features: Munroe (1976) has images of the male genitalia.
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: The larvae are social and feed on dogbanes (Apocynum spp.) that contain cardiac glycosides and are toxic to birds and mammals. One of the primary defenses of the older larvae is to regurgitate toxic gut contents when attacked by a predator (Grant, 2006). Females lay as many as 150 eggs per clutch on the underside of leaves in a fish-scale like configuration (Grant, 2005). The larvae feed on leaves and live together in a conspicuous nest that is made of leaves that are webbed together. The first two instars are a cryptic green color and feed between webbed leaves. Because of size and food constraints, they ultimately abandon the leaf shelters and feed in the open within the nest for the remainder of the larval period. Correlated with this is a progressive change of the body from green to becoming orange with black spots, a phenomenon that appears to reflect a change in selection from crypsis to aposematism in the later instars (Grant, 2007). The final instar builds a loose outer cocoon with a slightly tighter inner cocoon (BugGuide).
Larvae ID Requirements: Identifiable from good quality photos, especially where associated with known host plants.
Distribution in North Carolina
Distribution: Saucrobotys futilalis is a very wide-ranging species that occurs across most of the U.S. and adjoining areas in southern Canada, where it occurs from British Columbia to Labrador and Nova Scotia. The range in the U.S. extends from the New England states southward to Florida, and westward to California and the Pacific Northwest. In North Carolina, this species is local common in the Piedmont where the host plant is present and far less common in the Blue Ridge. It appears to be rare in the Coastal Plain where we have only two site records as of 2023.
County Map: Clicking on a county returns the records for the species in that county.
Flight Dates:
 High Mountains (HM) ≥ 4,000 ft.
 Low Mountains (LM) < 4,000 ft.
 Piedmont (Pd)
 Coastal Plain (CP)

Click on graph to enlarge
Immature Dates:
 High Mountains (HM) ≥ 4,000 ft.
 Low Mountains (LM) < 4,000 ft.
 Piedmont (Pd)
 Coastal Plain (CP)

Click on graph to enlarge
Flight Comments: In the eastern U.S. the adults mostly fly from May through September in different areas of the range. As of 2023, our records are from late-April through mid-August.
Habitats and Life History
Habitats: This species specialized on dogbanes (Apocynum spp.) and local populations are found in the proximity of the hosts, which includes open and often disturbed habitats such as abandoned fields, roadsides, powerline clearings, and other grassy and early-successional habitats.
Larval Host Plants: The larvae feed on species of Apocynum (Robinson et al., 2010). Munroe (1976) noted that his colleagues found larvae feeding on Butterfly Milkweed (Asclepias tuberosa) in Kentucky, but this seems to be an unusual record. In North Carolina, Indian-hemp (A. cannabinum) is the primary host, but Spreading Dogbane (A. androsaemifolium) is also presumably used in the mountains. As of 2023, we have no records of Saucrobotys using milkweeds. - View
Observation Methods: The adults are attracted to lights, and the communal larvae and their webs are often conspicuous on dogbanes.
Wikipedia
See also Habitat Account for Open Apocynaceous Forblands
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: GNR [S4S5]
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: This species can be locally common where the host plants are present and appears to be reasonably secure in North Carolina.

 Photo Gallery for Saucrobotys futilalis - Dogbane Saucrobotys Moth

Photos: 28

Recorded by: David George on 2023-09-03
Durham Co.
Comment: 		Recorded by: David George on 2023-08-29
Chatham Co.
Comment:
Recorded by: John Petranka on 2023-07-10
Person Co.
Comment: 		Recorded by: David George on 2023-06-22
Durham Co.
Comment:
Recorded by: Stephen Dunn on 2023-06-05
Orange Co.
Comment: 		Recorded by: Stephen Dunn on 2023-06-05
Orange Co.
Comment:
Recorded by: Dean Furbish on 2023-05-18
Wake Co.
Comment: 		Recorded by: Dean Furbish on 2023-05-18
Wake Co.
Comment:
Recorded by: Emily L Stanley on 2023-05-12
Yancey Co.
Comment: 		Recorded by: David George on 2022-08-29
Durham Co.
Comment:
Recorded by: David George on 2022-07-29
Durham Co.
Comment: 		Recorded by: David George, L. M. Carlson on 2022-07-14
Orange Co.
Comment:
Recorded by: David George, L. M. Carlson on 2022-07-03
Orange Co.
Comment: 		Recorded by: John Petranka on 2022-06-28
Durham Co.
Comment:
Recorded by: David George, L. M. Carlson on 2022-06-12
Orange Co.
Comment: 		Recorded by: David George on 2022-06-04
Orange Co.
Comment:
Recorded by: Dean Furbish on 2022-05-22
Wake Co.
Comment: 		Recorded by: David George on 2021-09-01
Durham Co.
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Recorded by: Dean Furbish on 2021-08-19
Wake Co.
Comment: Several communal woven-leaf nests found on Dogbane plants, each nest containing several larvae.		Recorded by: David L. Heavner on 2021-08-16
Chatham Co.
Comment:
Recorded by: F. Williams, S. Williams on 2019-08-04
Bertie Co.
Comment: 		Recorded by: Owen McConnell on 2018-06-06
Orange Co.
Comment: Folded in a Dogbane (Apocynum cannabinum) leaf
Recorded by: j.wyche on 2016-07-25
Gates Co.
Comment: 		Recorded by: j.wyche on 2016-07-25
Gates Co.
Comment:
Recorded by: F. Williams, S. Williams on 2015-08-30
Gates Co.
Comment: 		Recorded by: Lenny Lampel on 2015-06-02
Mecklenburg Co.
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Recorded by: Paul Scharf on 2011-04-21
Warren Co.
Comment: 		Recorded by: FKW on 2007-08-08
Gates Co.
Comment: