Orthoptera of North Carolina
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View Gryllidae Members: NC Records

Allonemobius allardi (Alexander & Thomas, 1959) - Allard's Ground Cricket


Taxonomy
Family: Gryllidae Subfamily: Nemobiinae Tribe: PteronemobiiniSynonym: Nemobius allardi
Comments: One of ten species in this genus, all of which occur in North America north of Mexico (Cigliano et al., 2017). Eight species have been recorded in North Carolina.
Identification
Field Guide Descriptions: Capinera et al. (2004); Elliot and Hershberger (2006); Himmelman (2009)Online Photographs: BugGuide, SINA, OSF (shots of specimens only), Google ImagesTechnical Description, Adults/Nymphs: Alexander and Thomas (1959); Howard and Furth (1986)SINA 539a.htm                                                                                  
Comments: A red-brown to blackish ground cricket (Alexander and Thomas, 1959). The head is brown with two to three darker stripes, which are usually not contrasting, particularly at the rear of the head, but forming more distinct spots at the top. Differs in coloration and pattern from A. socius, which has pale, contrasting stripes on the back of the head, and from A. tinnulus, which has a more reddish head and pronotum. However, allardi cannot be safely distinguished from A. walkeri and fultoni based on photos and can only be identified based on specimens or spectrograms (Howard and Furth, 1986).
Total Length [body plus wings; excludes ovipositor]: 9.2-11.2 mm, males; 8.9-12.9, females (Howard and Furth, 1986)
Structural Features: Both macropterous and micropterous individuals exist (Alexander and Thomas, 1959)
Singing Behavior: The song of Allonemobius allardi consists of a long series of downslurred pulses, similar in tonal quality to A. tinnulus, walkeri, and fultoni. The dominant frequency in all of these species ranges between 6-8.2 kHz (Howard and Furth, 1986; Elliot and Hershberger, 2006; SINA, 2017). In allardi, the number of pulses produced per second ranges from 10-17 (Elliot and Hershberger, 2006; SINA, 2017), with slower rates given at lower temperatures. This rate is faster than in tinnulus (5-8) but slower than walkeri and fultoni (24-25). Whereas the difference from tinnulus is fairly easy to hear, at least when both are heard under the same temperature conditions (see Elliot and Hershberger, 2006), song comparisons to walkeri and fultoni are most easily done through use of spectrograms. Distinguishing allardi from Anaxipha tinnulacita -- whose songs are very similar in pitch and pulse rate to allardi -- is more difficult, however, even using spectrograms. To separate those two species, information on the location of the song -- on the ground (allardi) or up in vegetation (tinnulacita) -- is usually required.
Recording playback at normal speed.

Download Video: "MP4"

Nymphal Stages and Development: Not described
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: Allonemobius allardi inhabits well-drained grassy and weedy habitats, including "lawns, pastures, fields, and roadsides" (Alexander and Thomas, 1959). It often occurs with A. walkeri, but tinnulus is usually found in xeric woodlands and fultoni in wetter, shadier, or marshier habitats (Alexander and Thomas, 1959; Howard and Furth, 1986).
Diet: Probably omnivorous
Observation Methods: Mostly easily detected by its song, which is given both day and night.
Abundance/Frequency:
Adult Phenology: Our records all come from the late summer and fall
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: GNR [SU]
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands
Comments: There are still too few records for this species in North Carolina to determine its distribution and conservation status. Records from the Piedmont need to be verified based on spectrograms or, preferably, specimens.

Image Gallery for Allonemobius allardi - Allard's Ground Cricket

Recorded by: Steve Hall and Bo Sullivan
Ashe Co.
Comment:
Recorded by: Jim Petranka
Madison Co.
Comment:

MP3 Gallery for Allonemobius allardi - Allard's Ground Cricket

1 Recorded by: Jim Petranka
Madison Co.
2020-08-23
Individuals were calling during mid-day from an infrequently mowed field; air temp. = 81F (27.2C); pulse rate = 17-18 per sec.