Beetles of North Carolina
Family (Alpha):
Scientific Name: Common Name:
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View Carabidae Members:
Members of Trechus:
4 NC Records

Trechus luculentus luculentus Barr, 1962 - No Common Name

Family: Carabidae Subfamily: Trechinae                                                             
Comments: One of 82 species in this genus that have been recorded in North America north of Mexico, 42 of which occur in North Carolina (Bosquet, 2012). Trechus luculentus belongs to subgenus Microtrechus and is included in the Nebulosus Species Group by Bosquet (2012). In addition to luculentus, 21 other species are included in this group, 18 of which occur in North Carolina and the rest in Tennessee.
Species Status: The type locality is Clingman's Dome in the Great Smoky Mountains (Barr, 1962). The nominate subspecies was described by Barr (1979)
Field Guide Descriptions: Online Resources: BugGuide, Wikipedia, GBIFTechnical Description, Adults/Nymphs: Barr (1962, 1979)                                                              
Comments: Members of this genus show too little variation in pattern for standard photographs to be used to identify particular species.
Total Length [body plus wings; excludes ovipositor]: 0.63-0.73 mm (Barr, 1979)
Structural Features: As a member of subgenus Microtrechus, only the first segment of front tarsus is enlarged in males. This species is distinguished from other members of its species group morphometrically and by features of the aedeagus (Barr, 1962, 1979).
Distribution in North Carolina
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
Habitats and Life History
Habitats: Although originally found at one of the highest elevations in North Carolina, Barr (1979) subsequently found it as low as 2,200', providing substantial connections between subpopulations throughout the central Great Smoky Mountains. Specimens have been found under rocks located beside springs and small streams, under moss mats, and under wet leaves and gravel.
See also Habitat Account for General Montane Mesic Forests
Diet: Predatory on small insects and other invertebrates
Observation Methods:
Abundance/Frequency: Barr (1979) noted that this subspecies is "always two to three times more abundant" than T. valentinae where they occur together.
Adult Phenology: Not enough information exists for this species to determine its phenology
Status in North Carolina
Natural Heritage Program Status: [SR]
Natural Heritage Program Ranks: GHTH [G23T23] [S1S2]
State Protection:
Comments: This subspecies is endemic to the Great Smoky Mountains but occurs at a number of locations and elevations within the National Park. Consequently, it is probably less vulnerable to climate change than other members of this genus, including the other subspecies of luculentus. Given its small geographic range, however, it cannot be considered to be completely secure.