Trichotichnus

A.Morawitz, 1863

Trichotichnus is a of in the , subtribe Harpalina, comprising more than 260 worldwide. The genus is divided into multiple subgenera including Trichotichnus s. str., Bottchrus, Iridessus, Amaroschesis, Harpaloxenus, and Parairidessus. Species occur primarily across the Palaearctic region, with significant diversity in the Himalayas, East Asia, and Korea. Many species exhibit , including (short-winged, flightless) forms that are geographically restricted.

Trichotichnus dichrous by (c) Nathan T. Jones, some rights reserved (CC BY), uploaded by Nathan T. Jones. Used under a CC-BY license.

Trichotichnus vulpeculus by (c) Wendy Jegla, some rights reserved (CC BY), uploaded by Wendy Jegla. Used under a CC-BY license.

Trichotichnus vulpeculus by no rights reserved, uploaded by Mirko Schoenitz. Used under a CC0 license.

Pronunciation

How to pronounce Trichotichnus: /trɪˈkɒtɪknəs/

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

Identification

Identification to level requires examination of male , particularly the lobe of the . Subgenera are distinguished by combinations of morphological characters including development, body proportions, and genitalic structure. species in the subgenus Bottchrus are grouped informally based on degree of reduction and aedeagus configuration. Species in the nominotypical subgenus often require comparison of tarsal proportions, pronotal shape, and elytral microsculpture.

Images

Habitat

Found in mountainous regions, particularly in the Himalayas and adjacent areas. Specific include leaf litter in forested areas, as documented for Korean . Elevational range spans from mid-elevation valleys to high mountain slopes, with many showing narrow geographic restriction due to limited ability.

Distribution

Primarily Palaearctic distribution. Documented from: Nepal (multiple districts including Baglung, Kaski, Solu Khumbu, Bhojpur, Dolakha, Lamjung, Nuwakot, Gorkha, Sindhupalchok, Taplejung), India (West Sikkim), China (Yunnan, Sichuan, Shaanxi), North Vietnam, North West Laos, and Korea. GBIF records indicate presence in Sweden and Vermont, USA. The shows highest in Himalayan and East Asian montane regions.

Behavior

Many exhibit , including (flightless) and (fully winged) forms. Sex-linked wing dimorphism has been documented in T. laevicollis and T. nitens. Brachyptery correlates with restricted geographic distributions and localized . Some species show populations with both winged and short-winged individuals co-occurring.

Similar Taxa

HarpalusBoth in subtribe Harpalina; Trichotichnus distinguished by more slender body form, different pronotal structure, and male
OphonusSimilar habitus; Trichotichnus separated by tarsal structure and characteristics

More Details

Taxonomic Structure

The contains six recognized subgenera: Trichotichnus s. str. (nominotypical), Bottchrus, Iridessus, Amaroschesis, Harpaloxenus, and Parairidessus. Recent taxonomic revisions have described numerous new , particularly from the Himalayan region and China, with 15 new species described from Bottchrus alone in 2017.

Wing Polymorphism

reduction is a major evolutionary theme in the . The subgenus Bottchrus is characterized by , while other subgenera contain both fully winged and species. This has significant biogeographic consequences, promoting in montane .