An emended description of Sminthurinus lawrencei Gisin 1963, with notes on the identification of black Sminthurinus species

Abstract

The black, globular springtail Sminthurinus lawrencei Gisin, 1963 has long been thought of as a rare species, known from only few localities in only three countries, up to and including 2020. This work describes the discovery of this species in other countries resulting from identification of newly collected specimens, a re-analysis of older collection material and scrutiny of publicly available high-definition images with location tags. This work includes the first records of this species from Canada, France and the Netherlands. Previously, the brief description of S. lawrencei by Gisin resulted in many researchers considering it to be a doubtful species. To identify similarly black-coloured Sminthurinus-species without characteristic pigmentation, reliance on the presence or absence of setae on the dentes of the furca is a crucial aid for proper identification. This has previously posed challenging due to the lack of proper systematic description of the positioning of these setae. In this work we describe a recent upsurge of recordings for S. lawrencei, describe its morphological characteristics and clarify the dental chaetotaxy (following Bretfeld 1999) to aid in the identification of Sminthurinus ‘niger’-group, which S. lawrencei is a member of. We confirm that S. lawrencei is a bona fide species, but vastly overlooked and should be looked for in Western Europe and North America. By contrast, S. niger (Lubbock, 1870) is likely to be much rarer in Western Europe than currently anticipated, with many past recordings likely representing other species, including S. lawrencei.