Nemastomatidae in the Holarctic

This opilionid family of predominantly small species shows a holarctic distribution. The nominate subfamily, Nemastomatinae Simon, 1879 has its strongholds in the West Palearctic with a distributional focus in central and southern Europe, Turkey and the Caucasus (Schönhofer 2013); a few recently discovered outliers extend the area to Central Asia and western China (Snegovaya 2010; Martens 2016, 2017; Zhang & Martens 2018). The subfamily comprises about 120 species (Schönhofer 2013; Martens 2016). The second subfamily, Ortholasmatinae Shear & Gruber, 1983 (Shear & Gruber 1983; Shear 2006, 2010) is distributed in East Asia including Japan (Martens 2019; Schwendinger & Gruber 1992), and the west coast of North America. Its area extends southward to Central America, the Mexican highlands and the Honduran tropics (Shear 2010; Cruz-Lopéz et al. 2018). This subfamily is much poorer in genera and species than Nemastomatinae; seven genera of the former are described and 18 of the latter. The majority of Ortholasmatinae species occur in western North America and in Central America (Martens 2019).