Orthoptera of North Carolina

Family (Alpha):

View	Gryllidae Members:	NC Records
Cycloptilum trigonipalpum (Rehn & Hebard, 1912) - Forest Scaly Cricket

Taxonomy

Family: Gryllidae	Subfamily: Mogoplistinae	Tribe: Mogoplistini
Comments: One of sixteen species in this genus that occur in North America north of Mexico (Love and Walker, 1979), six of which have been recorded in North Carolina. Trigonipalpum belongs to the Trigonipalpum Species Group (the Trilling Scaly Crickets), which includes two additional species, neither of which occurs in North Carolina.

Identification

Field Guide Descriptions: Capinera et al. (2004); Himmelman (2009)	Online Photographs: SINA, BugGuide, Google Images, iNaturalist, GBIF	Technical Description, Adults/Nymphs: Love and Walker (1979)	SINA 442a.htm
Comments: A slender-bodied, elongated Scaly Cricket. The cuticle of the head, pronotum, and legs are yellow to brown, and the abdomen is blackish (Love and Walker, 1979). The entire body is covered with pale, translucent scales, at least when fresh.
Total Length [body plus wings; excludes ovipositor]: 6.8-7.1 mm, males; 7.8-8.5 mm, females (Blatchley, 1920)
Structural Features: As in other Scaly Crickets, the cerci are long and fairly thick, the hindwings are missing (the tegmina as well in the females), and the pronotum is elongated -- in males of this species as well as slossoni, it usually completely covers the tegmina, unlike the case in the Bidens Complex. In the Trigonipalpum Group, the terminal segment of the palpus is conical and strongly widened at the end, with a straight, strongly oblique margin -- the short side of this segment is only half as long as the longest side. The internal male reproductive structures are distinctive (see Love and Walker, 1979 for a detailed description).
Singing Behavior: Songs of this species consist of short, buzzy trills, each lasting from 0.25 to 1 second and consisting of over 50 syllables per second (Love and Walker, 1979). Pauses between trills are about the same length. In North Carolina, Fulton (1932) noted that trills are given in sequences of 3 to 4, at a rate of 0.6 trills per second. At 77 F (25 C), the per trill rate is about 57 pulses per second (Love and Walker, 1979), with the dominant frequency about 6.7 kHz (Capinera et al., 2004). These trills are longer, less melodious, and higher pitched than those of the two Orocharis species, which often sing in the same habitats at the same time. Cycloptilum slossonae has a similar short trill at about the same dominant frequency but with less than 35 syllables per second. Trills of slossoni are also shorter in duration and repeated somewhat more rapidly. Love and Walker noted that the songs of slossoni are more buzzy due to the grouping of the pulses into pairs within the trill.
Recording playback at normal speed.
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Nymphal Stages and Development: Undescribed

Distribution in North Carolina


County Map: Clicking on a county returns the records for the species in that county.


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

Habitats and Life History

Habitats: Love and Walker (1979) state that this species prefers broadleaf, deciduous trees, especially where there are frequent branches, vines, and dead leaves; pines are also used, at least where grapes and other vines are present. In North Carolina, we have a number of records from horticultural trees in residential neighborhoods.

Diet: Undescribed but possibly omnivorous

Observation Methods: Most easily detected by their songs but at least some species in this genus have been observed at bait

Abundance/Frequency: Too little information exists to estimate the frequency of occurrence or abundance of this species in North Carolina

Adult Phenology: Fulton (1951) shows records for this species in the vicinity of Raleigh from mid-August to mid-October. We also have at least one record from July from the Fall-line near the Virginia border.

See also Habitat Account for General Hardwood Forests

Status in North Carolina

Natural Heritage Program Status:

Natural Heritage Program Ranks: [GNR] [S5?]

State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands

Comments: This species appears to have a broad range within the state and will probably be found over most of our area eventually. It does not appear to be specialized in terms of habitat and can make use of at least suburban environments. Consequently, it appears to be secure within the state.

Image Gallery for Cycloptilum trigonipalpum - Forest Scaly Cricket
	Recorded by: Steve Hall Chatham Co. Comment: 52 syllables per second within trills @ 8.2 kHz; trills are about 0.4 seconds long, with the trill rate approximately 0.85 per second; recorded in a floodplain forest	Recorded by: R. Newman Carteret Co. Comment:
	Recorded by: Steve Hall Chatham Co. Comment:	Recorded by: Ken Kneidel Mecklenburg Co. Comment:
	Recorded by: John Petranka Warren Co. Comment:	Recorded by: John Petranka Warren Co. Comment:
	Recorded by: Michael P. Morales Cumberland Co. Comment:	Recorded by: Michael P. Morales Cumberland Co. Comment:
	Recorded by: Michael P. Morales Cumberland Co. Comment:	Recorded by: Steve Hall and Bo Sullivan Moore Co. Comment: Heard singing in a tree near the house
	Recorded by: Ken Kneidel Mecklenburg Co. Comment:	Recorded by: Ken Kneidel Mecklenburg Co. Comment:
	Recorded by: Steve Hall Iredell Co. Comment: 10:08, 77 F; recorded in vegetation growing along a road	Recorded by: Steve Hall, Bo Sullivan, Jim Petranka, Becky Elkin, and Rob Gilson Iredell Co. Comment: At beer-banana bait
	Recorded by: Steve Hall Wake Co. Comment:	Recorded by: Steve Hall and Bo Sullivan New Hanover Co. Comment:

Cycloptilum trigonipalpum (Rehn & Hebard, 1912) - Forest Scaly Cricket

Image Gallery for Cycloptilum trigonipalpum - Forest Scaly Cricket