The genus Alwisia (Myxomycetes) revalidated, with two species new to science.

Based on morphological investigations and a phylogeny constructed with partial sequences of the SSU rDNA gene, we revalidate the genus Alwisia and propose the combination Alwisia bombarda Berk. & Broome to be used against Tubifera bombarda (Berk. & Broome) G.W. Martin. Two new species, Alwisia morula and A. repens, are described based on material collected respectively in Costa Rica and Australia. Both new species lack a capillitium and possess individually stalked subspherical sporothecae. Alwisia repens differs from A. morula by its procumbent stalks and iridescent peridium. A comparison of 83 sequences of species in the genera Lycogala, Reticularia and Tubifera with a recent two-gene phylogeny of the bright-spored myxomycetes resulted in a similar topology of both Bayesian and maximum likelihood trees and placed A. bombarda, A. morula and A. repens in one well delimited clade within Reticulariaceae.