Abstract: MSCquartets (Rhodes et al., Bioinformatics 2021) is an R package for species tree and network inference under the multispecies coalescent model. Among other things, it provides several fast quartet-based methods, including TINNIk (for inference of the tree of blobs), NANUQ and NANUQ+ (for level-1 network inference), and a hypothesis test for detecting hybridization. MSCquartets is available on CRAN at cran.r-project, and many of its functions are also accessible through a Shiny app at hector-banos.shinyapps.io/MSCq.