Moths of North Carolina
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28 NC Records

Hypagyrtis brendae R.L. Heitzman, 1975 - Brenda's Hypagyrtis Moth


Hypagyrtis brendae
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Hypagyrtis brendae
Taxonomy
Superfamily: Geometroidea Family: GeometridaeSubfamily: EnnominaeTribe: BistoniniP3 Number: 91a1075 MONA Number: 6657.00
Comments: This New World genus contains 7 species, 1 neotropical and 6 from North America, three of which occur in North Carolina (piniata may also be possibly present in the mountains -- Wagner et al., 2001). This genus shows a large range of variation, however, and its taxonomy still appears to be unsettled. Forbes (1948) stated that "the species or forms of this genus are completely confused and show no satisfactory differences in genitalia -- they may be merely races and strains, but breeding from known foods will be needed to make sure."
Species Status: This species was first discovered in North Carolina -- and presumably the entire East Coast -- in 1994 by S. Hall, who collected 210 individuals in a single light trap set out in a dense, mature stand of Atlantic White Cedars located on the mainland of Dare County (Fussell et al., 1995). Specimens from North Carolina have since been barcoded and are distinct from those from the mid-west, the type locality of the species and we suspect that North Carolina specimens are an undescribed species. The only other population of Hypagyrtis brendae that has been found in association with Atlantic White Cedars is located in the Florida Panhandle (Kons and Borth, 2007).
Identification
Field Guide Descriptions: Covell (1984)Online Resources: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Heitzman (1974)Technical Description, Immature Stages: None are known.                                                                                 
Adult Markings: Size and coloration are similar to esther, with the subterminal area shaded with rusty brown and the medial and basal areas shaded with grayish-brown or violet-gray (Macaria transitaria is also very similar but has simple rather than pectinate antennae and a different wing shape). The median line is much more developed in brendae than in esther (where it is typically missing or obscure), forming a wide diffuse band on the hindwing in particular. On the forewing, the median line runs straight and obliquely across the wing, converging with the postmedian at the inner margin. Both of these lines meet the inner margin at an acute angle whereas in esther, the postmedian makes a perpendicular intersection with the inner margin (see Heitzman, 1974, for a description and illustration). In brendae, the dark line component of the post median line is also narrow, sharp and distinct. As in other Hypagyrtis, females are larger, longer-winged, and have a more scalloped outer margin on the hindwing.
Adult Structural Features: Antennae are pectinate in the males, simple in the females. In the male the median area of the gnathos is pinched so that it resembles a spoon, unlike in the other two species. In the female the signum is quadrate and the ostial area is larger and better sclerotized. These characters seem distinct but additional dissections are needed to be sure.
Structural photos
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: Larvae and pupae do not appear to have been described. It seems likely that the eggs overwinter.
Larvae ID Requirements: Identifiable only through rearing to adulthood.
Distribution in North Carolina
Distribution: Restricted to stands of Atlantic White Cedar in the Outer Coastal Plain and Sandhills.
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
Flight Comments: Covell (1984) reports two broods in the Mississippi Valley. Our data indicate that there may be two or three broods or possibly that the species flies during most of the growing season.
Habitats and Life History
Habitats: Nearly all of our records come from peatland habitats containing stands of Atlantic White Cedar. Only a single specimen has been caught at a site that did not have any White Cedar present but where there may have been some undiscovered stands in the vicinity. All the rest came from traps placed within stands of this tree. Populations have been found in large peatdomes, Carolina Bays, and Streamhead Atlantic White Cedar communities in the Sandhills.
Larval Host Plants: We have not reared larvae to maturity but are confident that Atlantic White Cedar (Chamaecyparis thyoides) is the foodplant in North Carolina. Host plants do not appear to have been described in the Midwest, but Atlantic White Cedar does not occur in that area. - View
Observation Methods: Comes very well to 15 watt UV lights, with up to 215 captured in a single trap at the Dare County Bombing Range. It is unlikely to come to bait or to flowers.
Wikipedia
See also Habitat Account for Atlantic White Cedar Forests
Status in North Carolina
Natural Heritage Program Status: SR
Natural Heritage Program Ranks: G4 S2S3
State Protection: Listed as Significantly Rare by the Natural Heritage Program. That designation, however, does not confer any legal protection, although permits are required to collect it on state parks and other public lands.
Comments: This species is an extreme specialist on a now highly restricted host plant and habitat type. Atlantic White Cedar is a highly prized timber species and many stands -- including most of those on the Dare County Bombing Range where this species was originally found in the state -- have been cut. Peatdomes, including the one on the Dare County mainland, are also vulnerable to the effects of sea level rise, with vast acreages expected to be lost within the foreseeable future. Any loss, degradation, or fragmentation of the habitat used by such an extreme habitat specialist may make it increasingly difficult for it to recover from environmental perturbations. We judge the risks to this species accordingly as very high. If it is discovered to represent a separate species from the Midwestern form, as seems likely, its global status will also need to be revised.

 Photo Gallery for Hypagyrtis brendae - Brenda's Hypagyrtis Moth

Photos: 2

Recorded by: Jim Petranka and Bo Sullivan on 2021-08-10
Richmond Co.
Comment:
Recorded by: Jim Petranka, Bo Sullivan and Steve Hall on 2021-06-09
Richmond Co.
Comment: