Stenolophus

Seedcorn Beetles

Species Guides

Stenolophus anceps(Double-edged Harp Ground Beetle)
Stenolophus binotatus
Stenolophus carbo(Burned Harp Ground Beetle)
Stenolophus cincticollis
Stenolophus comma(Common Stenolophus Beetle)
Stenolophus dissimilis
Stenolophus flavipes
Stenolophus fuliginosus(Sooty Harp Ground Beetle)
Stenolophus fuscatus(Black-banded Harp Ground Beetle)

Stenolophus is a large of ground beetles in the Carabidae, comprising over 190 described distributed across the Palearctic, Nearctic, Near East, and North Africa. Commonly known as seedcorn , several species are significant agricultural pests of corn and other crops. The genus includes both and potentially multivoltine species depending on geographic location.

Stenolophus fuliginosus by (c) Owen Strickland, some rights reserved (CC BY), uploaded by Owen Strickland. Used under a CC-BY license.

Stenolophus binotatus by (c) Annika Lindqvist, some rights reserved (CC BY), uploaded by Annika Lindqvist. Used under a CC-BY license.

Pronunciation

How to pronounce Stenolophus: /stɛˈnɒləfəs/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Small ground beetles, typically under 10 mm in length. within Stenolophus can be distinguished from similar carabid by subtle morphological characters including elytral punctation patterns and male genitalia. Specific identification to species level often requires examination of structure and other microscopic features. The genus is part of the tribe Harpalini, characterized by thread-like and typically .

Images

Habitat

Agricultural fields, particularly corn fields; grassy areas, field margins, and areas with protective debris where overwinter. Some occupy cropland exclusively.

Distribution

Palearctic (including Europe), Nearctic (North America), Near East, and North Africa. In North America, such as S. comma and S. lecontei range from Oregon to Maine and from southern Canada through the central and eastern United States.

Seasonality

overwinter and emerge in spring to feed, mate, and oviposit. New adults emerge in late summer to early fall, feed briefly, then seek sites. S. comma is ; S. lecontei may produce a partial second in southern regions.

Diet

Seeds and seedlings of corn (Zea mays) and other plants; feed on various plant materials.

Host Associations

Zea mays (corn) - pestprimary agricultural ; larvae feed on planted seeds and emerging seedlings
various other plant seeds and seedlings - pestlarvae feed on seeds and seedlings of multiple plant

Life Cycle

Approximately one year. stage followed by three larval instars, then in earthen in late summer. emerge in late summer to early fall. occurs as adults in protected sites.

Behavior

are and hide in soil cracks or under debris during daylight hours. Attracted to corn fields at planting time. New adults feed briefly in late summer before seeking sites. Significant seed and seedling documented in agricultural settings.

Ecological Role

Agricultural pest affecting corn establishment and yield through seed and seedling . Serves as for ectoparasitic mites in Crotalomorphidae and Podapolipidae (Eutarsopolipus elzingai, E. brevichelus, Crotalomorpha camini).

Human Relevance

Several (particularly S. comma and S. lecontei) are economically important pests of corn, damaging planted seeds and emerging seedlings. Management includes insecticidal and at-planting soil applications. The is referenced in agricultural extension materials for corn pest management.

Similar Taxa

Other Harpalini generaSimilar small ground beetle ; distinguished by genitalic and punctation characters
AgonumSimilar size and ; Stenolophus historically placed in synonymy with Agonoderus, now treated as distinct

More Details

Ectoparasitic mite associations

Documented for mites in Crotalomorphidae and Podapolipidae: S. comma and S. lecontei host Eutarsopolipus elzingai, E. brevichelus, and Crotalomorpha camini; S. fuliginosus hosts E. brevichelus; S. maculatus and S. lineola host E. elzingai.

Subgeneric classification

The includes multiple subgenera: Agonoderus, Astenolophus, Egadroma, and Stenolophus sensu stricto. One fossil , †S. religatus, is known from the Florissant Formation.