Orthoptera of North Carolina
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View Gryllidae Members: NC Records

Anaxipha litarena Fulton, 1956 - Beach Trig


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Taxonomy
Family: Gryllidae Subfamily: Trigonidiinae Tribe: Trigonidiini
Comments: One of thirteen species in this genus that occur in North America north of Mexico (SINA, 2017); nine have been recorded in North Carolina. Litarena was placed in the Litarena Species Group by Walker and Funk (2014), which also includes rosamacula, a species recently added to the North Carolina list.
Species Status: The type locality of this species is Carolina Beach, North Carolina (Fulton, 1956).
Identification
Field Guide Descriptions: Online Photographs: SINA, Google ImagesTechnical Description, Adults/Nymphs: Fulton (1956); Walker and Funk (2011)SINA 613a.htm                                                                                  
Comments: A very small, pale tan Trig. Unlike members of the Exigua Group, it lacks a stripe on the lateral face of the femur (Walker and Funk, 2014). That separates it from tinnula, which occupies the same habitats but not delicatula, which also lacks the stripe on the femur. Structural features may need to be examined to distinguish it from that species.
Total Length [body plus wings; excludes ovipositor]: 6.1-7.4 mm, males; 5.0-6.5 mm, females (Walker and Funk, 2014)
Structural Features: Stridulatory file with about 72 teeth (range 65-77); ovipositor 1.6-1.7 mm, ratio of length of hind femur to ovipositor 2.4-2.8 (Walker and Funk, 2014). Parameres of the males have recessed lobes which are absent from other members of this genus recorded in North Carolina.
Singing Behavior: Songs consist of short trills -- chirps -- with a within-chirp pulse rate of about 66 pulses per sec at 77 F (25° C) and a dominant frequency of 5.9 kHz. Anaxipha delicatula -- which is found in the same tidewater areas at about the same season -- also has songs consisting of short pulse trains, but with a faster within-chirp pulse rate of about 79 pulses per sec at 77 F (25° C), but with a very similar dominant frequency at 5.7 kHz. Walker and Funk further distinguish these two species by characteristics of the pulse train (PT = chirp): "In litarena the PT rate is usually slower, the PT duration usually greater." They note, however, that "in Florida the PT phrasing seems always to be useful in separating the two species by ear but this may not be the case in coastal North Carolina."
Nymphal Stages and Development: Apparently undescribed but unlikely to be distinguishable
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)

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Habitats and Life History
Habitats: Fulton recorded this species from a fairly wide range of tidewater habitats in North Carolina, including a dry sand ridge at Carolina Beach (possibly the tract of Coastal Fringe Sandhills where the state park is now located), beach dunes, salt marshes, and fresh-water marshes.
Diet: Apparently unrecorded; possibly omnivorous
Observation Methods: Singing males are most easily detected but they may also be captured using sweep netting
Abundance/Frequency: We have no information on either the frequency of observations or abundance of this species in North Carolina
Adult Phenology: Fulton (1956) recorded litarena in North Carolina from June 11 to September 11
Status in North Carolina
Natural Heritage Program Status: [W3]
Natural Heritage Program Ranks: GNR S3S4
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 be restricted to the Tidewater region of the state, where it has been recorded in marshes and dunes. With so few current records, we still know too little about the distribution, abundance, and exact habitat requirement of this species to make an accurate assessment of its conservation status.