Moths of North Carolina
Scientific Name:
Common Name:
Family (Alpha):
« »
View PDFGeometridae Members: 56 NC Records

Macaria signaria (Hübner, [1809]) - Pale-marked Angle


Taxonomy
Superfamily: Geometroidea Family: GeometridaeSubfamily: EnnominaeTribe: MacariiniP3 Number: 910766.00 MONA Number: 6344.00 MONA Synonym: Semiothisa signaria; Semiothisa fraserata
Comments: One of 25 species in this genus -- commonly known as Angles (as in angular, referring to the wing shape) -- that occur in North America; 17 have been reported from North Carolina
Species Status: Signaria is included in the conifer-feeding signaria species group by Ferguson (2008), of which pinistrobata, fissinotata, and granitaria are the other members that occur in North Carolina (two others, marmorata and oweni, have also been doubtfully recorded). Two forms of signaria have been reported in North Carolina (Ferguson, 2008), the typical form and a larger, brighter form, fraserata, which was originally described by Ferguson (1974) as a separate species. In 2008, Ferguson decided that fraserata was most likely only an environmental form of signaria, with intermediates between fraserata and and more typical forms found in a wide range of sites.
Identification
Field Guide Descriptions: Covell (1984; as Semiothisa signaria); Beadle and Leckie (2012)Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONATechnical Description, Adults: Ferguson (2008)Technical Description, Immature Stages: Maier et al., 2013                                                                                 
Adult Markings: Similar to other Macaria in their angled hindwings and sub-falcate forewings, but members of the signaria species group are distinguished from all other North Carolina Macaria in possessing a grayish rather than a yellowish head (Forbes, 1948). All members of this group are generally similar in their pattern of lines and spots. Signaria is most similar to pinistrobata, but the typical form has a more even shading of gray brown rather than the more black, gray, and white shading of pinistrobata; the pre-apical costal spot (upper end of the subterminal line) is reddish brown in signaria, particularly in the males, but strong, very dark blackish-brown (sometimes reddish) and quadrangular in pinistrobata. In form fraserata of signaria, however, these differences are less pronounced, with fraserata showing more contrast between the white ground color and possessing darker, blacker lines (Ferguson, 1974). Fissinotata is similar to typical signaria in being fairly lightly marked and grayish-brown but has a straight postmedian line, which is wavy in signaria; the medial line is also often weak or missing in fissinotata but usually present in signaria. Granitata is much more contrastingly marked than the other species and easily distinguished from the lightly and evenly marked form of signaria (see Ferguson, 1974, 2008, and Covell, 1984, for details).
Adult Structural Features: All members of the signaria group have males with foveae (Ferguson, 2008).
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: Larvae are green with pale lateral stripes and a frosted dorsal surface; the head has dark brown markings (Maier et al., 2013). Several other conifer-feeding species of Macaria have similar larvae and fissinotata, in particular, overlaps with signaria in their use of Hemolock and Spruce; larvae found on those hosts need to be reared for a positive identification (Maier et al., 2013).
Larvae ID Requirements: Identifiable only through rearing to adulthood.
Distribution in North Carolina
Distribution: All of our records come from the Mountains, but from the entire north-south range in the state.
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: Occurs throughout the growing season, but our data are not sufficient to determine if there are separate flights.
Habitats and Life History
Habitats: The majority of our records come from high elevation conifer forests, including from the summits of Mt. Mitchell, Grandfather Mountain, Roan Mountain, and Clingman's Dome. In those areas, all three of the main host plants are likely to be used. Records from lower elevations come primarily from coves and riparian areas, including Smokemont, Deep Creek, and Cataloochee in the Great Smokey Mountains National Park and New River State Park in Ashe County, all sites where Hemlocks are likely to be used. Carolina Hemlock also appears to be used, including on at least a few drier ridges, such as Bluff Mountain and several of the peaks around Highlands.
Larval Host Plants: Oligophagous, feeding a wide range of conifers. Ferguson (1974) lists Spruce, Fir, Hemlock as the most important hosts (Larch and Douglas Fir are also included but do not naturally occur in North Carolina); form Fraserata was believed to be associated with Fraser Fir. Ferguson also mentions that pines are used but that they may not be preferred, particularly in the East.
Observation Methods: Comes well to 15 watt blacklights but we do not have any records from either bait or flowers.
Wikipedia
See also Habitat Account for Montane Cool Mesic Conifer Forests
Status in North Carolina
Natural Heritage Program Status: [W3]
Natural Heritage Program Ranks: G5 [S4]
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: Two of the main host plants used by this species -- Fraser Fir and Eastern Hemlock -- are currently being decimated by exotic species of Adelgid. Form fraserata appears to have been particularly hard hit by loss of Fraser Fir forests (Ferguson, 2008). While Spruce is still fairly plentiful at high elevations, it may also become far more restricted due to the effects of global climate change. Macaria signaria is currently not being tracked by the Natural Heritage Program but we recommend that it be considered for inclusion on the Watch List and its status monitored along with other species associated with high elevation forests.

 Photo Gallery for Macaria signaria - Pale-marked Angle

Photos: 3

Recorded by: Jim Petranka, Becky Elkin, Steve Hall and Bo Sullivan on 2019-07-30
Yancey Co.
Comment:
Recorded by: Jim Petranka, Becky Elkin, Steve Hall and Bo Sullivan on 2019-07-30
Yancey Co.
Comment:
Recorded by: Vin Stanton on 2018-08-29
Buncombe Co.
Comment: