Leiobunum politum

Leiobunum politum is a species of harvestman in the family Sclerosomatidae. It is a medium-sized North American species widely distributed in the eastern and southeastern United States, and is especially common in the Appalachian Mountains.^{[1][2][3] [4]}

Leiobunum politum is a medium-sized harvestman. Males are about 3.5–5.0 mm in body length and females about 4.5–6.5 mm.^[4] The body is generally yellow-brown, with a dark brown to black ocular tubercle bearing small sharp spines.^[4]

Males usually lack prominent dorsal markings, while females may show a variably developed median abdominal mark.^[4] The species can be distinguished from closely related species by the morphology of the male penis and the size of the genital operculum.^[4]

Leiobunum politum occurs widely across the eastern and southeastern United States.^[4] It has been reported from the Appalachian Mountains from Maryland south to northern Florida, and westward into Mississippi, Louisiana, eastern Arkansas, and Illinois.^[4]

Specimens have been collected throughout much of the Appalachian region and adjacent areas, where the species inhabits forested habitats.^[4]

Leiobunum politum was originally described by Clarence M. Weed in 1889 from Champaign County, Illinois.^[4] Early descriptions relied heavily on characters such as body size, leg length, and coloration.^[4]

Later studies found that many of these characters are highly variable and not always reliable for distinguishing species of Leiobunum.^[4] McGhee (1977) demonstrated that some specimens previously identified as L. politum actually represent the similar species Leiobunum bracchiolum, which had often been confused with it due to overlapping external features.^[4]

More reliable characters for separating the species include the morphology and size of the male penis and the length of the genital operculum.^[4]