Moths of North Carolina
Scientific Name:
Common Name:
 Family (Alpha):
« »
View PDFSesiidae Members:
Paranthrene Members:
14 NC Records

Paranthrene simulans (Grote, 1881) - Hornet Clearwing

Paranthrene simulans
view caption 		Paranthrene simulansParanthrene simulansParanthrene simulans
Taxonomy
Superfamily:
Sesioidea		 Family:
Sesiidae		Subfamily:
Tinthiinae		Tribe:
Paranthrenini		P3 Number:
55a0059		 MONA Number:
2527.00		 Other Common Names:
Red Oak Clearwing, Golden Oak Borer
Comments: North America has 136 or more species in the family Sesiidae, with 37 species found in North Carolina. Many are similar in appearance to one another, and some are significant pests of commercial crops. Almost all are mimics of wasps and hornets.
Identification
Field Guide Descriptions: Online Resources: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Engelhardt (1946); Solomon (1995).Technical Description, Immature Stages: MacKay (1968); Solomon (1995)                                                                                 
Adult Markings: Paranthrene simulans is a large black and yellowish to yellowish-orange species that closely resembles the queens of native hornets (Vespa spp.). The resemblance includes its coloration, flight behavior and resting behavior where the abdomen is nervously moved about (Engelhardt, 1946). The coloration and patterning is variable, with the abdomen mostly yellow, but more commonly with black and yellowish striping. The forewing is shaded brown on the costal half, while the hindwing is transparent. The females closely resemble the males, but are larger, have heavier brown dusting on the forewing, and have a simple antenna with a touch of yellow at the inner base. This species is geographically and locally variable, with Coastal Plain populations often having forms with a golden abdomen with black striping, along with a more prominent lateral yellow stripe along the side of the thorax. These were previously treated as a separate species (P. palmii; Engelhardt, 1946), but have since been synonymized with P. simulans. Intermediates between the two forms are commonly encountered locally.

The following detailed description of the males is based on that of Engelhardt (1946). The antenna is bipectinate and black with brown tips. The labial palp is yellow with black at the base and along the sides. The head is black, with the eyes margined broadly with yellow in the front, while the collar is yellow behind and black in the front. The thorax is black with a yellow spot on the posterior margin, immediately below the collar on each side, in front of the forewing and immediately below the forewing. The tegulae is prominently striped with yellow on the lower half, and there is a black-and yellow tuft on the metathorax. The abdomen is variable in patterning and coloration, with varying levels of yellow or orangish-yellow to golden scales covering each segment. A common pattern is for segment 1 to be mostly black, with the remaining segments having yellow and black banding. Some specimens may have the black bands well-developed, while others may have them greatly reduced or absent. The anal tuft is short and compact, with a mix of yellow and black scales. The posterior tibia is yellow and shaded with rust and black scales, while the tarsi vary from yellowish to orange. The forewing is heavily dusted with brownish-black scales that are most concentrated on the costa half and on the middle portion of the inner margin, while the region around the anal margin tends to be translucent. The discal mark on the forewing is indicated by denser, brownish scales, and the hindwing is transparent with a brownish fringe and brown veins.

Paranthrene pellucida is a sibling species of P. simulans and is morphologically indistinguishable from the latter except for the absence of extensive dark dusting on the forewing. Where they occur sympatrically, P. pellucida flies about a month later than P. simulans so that the flight seasons only slightly overlap. These two species also show no obvious differences in the male and female genitalia and have very similar life cycles, with a two-year larval period (Eichlin and Duckworth, 1988). As of 2024, the flight season records that we have for North Carolina do not overlap, with P. simulans flying in May and June, and P. pellucida flying in July.
Wingspan: Males 27-30 mm; females 30-33 mm (Engelhardt, 1946).
Forewing Length: 12-18 mm (Eichlin and Duckworth, 1988).
Adult Structural Features: see below.
Structural photos
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: The larvae bore into the trunks and branches of oaks and American Chestnut, and may also attack young nursery stock. The following life history account is based on Solomon (1995) and Soloman and Morris (1966), and mostly based on work done in southern populations. The adults emerge in April through June (June and July farther north) and mate during the late afternoon on the day of emergence. Females can produce up to 459 light-brown eggs that are laid in bark crevices and mostly near tree bases. Development to hatching takes 15-18 days, and the young larvae first bore ovoid chambers in the inner bark. As they grow, they typically burrow into the wood at an upward angle for 4-4.5 cm, then angle parallel to the stem for another 5-6 cm. The completed galleries are around 9-10 cm long and 9-10 mm in diameter. Loose clumps of frass that are held together with silk often hang from the burrow entrances or can be found on the ground near tree bases. Boring in small samplings and stems can also induces gall-like swellings where the tissue is damaged. Larvae feed throughout the warmer months of their first year, overwinter in their galleries, then resume feeding the next year through the fall. They then construct a slightly enlarged area in the gallery and overwinter a second time. With the spring warm-up, the larva enlarges the gallery so that it reaches the bark surface, then constructs an escape hatch with an easily-ruptured, parchment-like cover that allows the pupa and adult to emerge. The protruding pupal skins often remain for months on the bark. The older larvae have a black head, a yellowish-brown thoracic shield and a purplish-brown abdomen and can reach 22-30 mm in length at maturity (MacKay, 1968).

Engelhardt (1946) and Solomon (1995) noted that the life cycle requires two years and that local populations have large emergences every other year that are followed by very few adults emerging in alternate years. Both authors noted that woodpeckers often prey on the larvae in galleries, particularly during the winter months, and may play an important role in population regulation.
Distribution in North Carolina
Distribution: Paranthrene simulans is endemic to the eastern US and a portion of southern Canada (Manitoba; Ontario; Quebec; Nova Scotia). In the US the range extends from southern Maine, New Hampshire and Vermont southward along the Atlantic Seaboard to central Florida, and westward to central Texas, central Oklahoma, eastern Kansas, Iowa and Minnesota. As of 2024, we have scattered records from all three physiographic regions of the state.
County Map: Clicking on a county returns the records for the species in that county.
Paranthrene simulans
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: The adults have been documented from March through October in different areas of the range, with a seasonal peak commonly in May through July. As of 2024, our records are from early-May through late-June.
Habitats and Life History
Habitats: Local populations are generally found in hardwood forests or residential settings with oaks, including habitats that range from bottomland forests to more xeric habitats.
Larval Host Plants: The larvae feed on American Chestnut (Castanea dentata) and a wide variety of oaks, including members of both the red oak and white oak groups (Engelhardt, 1946, Brown and Mizzel, 1993; Solomon, 1995; Robinson et al., 2023). The reported hosts include White Oak (Quercus alba), Emory Oak (Q. emory), Bear Oak (Q. ilicifolia), Chestnut Oak (Q. montana), Cherrybark Oak (Q. pagoda), Pin Oak (Q. palustris), Northern Red Oak (Q. rubra), Shumard Oak (Q. shumardii), Nuttall's Oak (Q. texana), and Black Oak (Q. velutina). Engelhardt (1946) and Solomon (1995) noted that a variety of deciduous and evergreen scrub oaks are also used in Florida. - View
Observation Methods: The adults are diurnally active and do not visit lights. They can be found around infested trees, but are most easily collected using traps with artificial pheromone lures.
Wikipedia
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: GNR [S3S4]
State Protection:
Comments: This species is widespread within North Carolina and is probably more common that records suggest due to its two-year population cycle and relatively short flight season.

 Photo Gallery for Paranthrene simulans - Hornet Clearwing

Photos: 6

Recorded by: Richard Teper on 2021-06-26
Orange Co.
Comment: 		Recorded by: Jim Petranka and Becky Elkin on 2019-05-26
Madison Co.
Comment:
Recorded by: Jim Petranka and Becky Elkin on 2019-05-24
Madison Co.
Comment: 		Recorded by: Jim Petranka and Becky Elkin on 2019-05-24
Madison Co.
Comment:
Recorded by: J.B. Sullivan on 2017-06-06
Ashe Co.
Comment: Nominate form. Confirmed by Bill Taft		Recorded by: J.B. Sullivan on 2017-05-03
Carteret Co.
Comment: Form palmii