Abstract
A new species, Isotogastrura praiana sp. nov., is described and illustrated based on the specimens collected from Rio de Janeiro, Southeastern Brazil. The new species is more similar to Mexican Isotogastrura ahuizolti Palacios-Vargas & Thibaud with respect to presence of two pre labral microchaetae and six sensillae on fourth antennal segments. Diagnostic features of new species are absence of sensilla D and presence of sensilla E on fourth antennal segments, distributing dorsal tubercles from second thoracic segment to third abdominal segment and greyish body color.