A new species of <i>Leptolalax</i> (Anura: Megophryidae) from northern Vietnam.

We describe a new, medium-sized Leptolalax species from Vietnam. Leptolalax petrops sp. nov. is distinguished from its congeners by a combination of having a medium-sized body (23.6-27.6 mm in 21 adult males, 30.3-47.0 mm in 17 adult females), immaculate white chest and belly, no distinct black markings on the head, highly tuberculate skin texture, toes lacking webbing and with narrow lateral fringes, and a call consisting of an average of four notes and a dominant frequency of 5.6-6.4 kHz (at 24.5-25.3 °C). Uncorrected sequence divergences between L. petrops sp. nov. and all homologous DNA sequences available for the 16S rRNA gene are >8%.