Invasive species are usually managed after their introduction and spread, which is often expensive and ineffective. If potentially invasive, non-native species are identified and tracked closer to introduction, management could become more proactive and cost-effective. However, early identification of invasives is often challenging, as non-native species can be similar both genetically and morphologically to closely-related, native species. Misidentification is a common occurrence that can result in a potential invasive going unnoticed. Called cryptic invasion, this results in the spread of a non-native species going undetected because it is morphologically similar to a native species or scientific names are unresolved or misapplied. Unclear species boundaries are at the root of cryptic invasion, and fine-scale genetic and morphological data are needed to help define and identify all species present. Rat’s tail grasses (Sporobolus indicus complex) have been inconsistently classified in literature as containing anywhere between one to twelve species. The Sporobolus indicus complex exhibits variation in plant size, flowering structures, and fruit morphology, but these characters form a gradient of morphology between described species. Additionally, the complex is globally-distributed, and many species are invasive or naturalized outside of their native ranges. Abnormally tall Rat’s Tail grasses were observed and recorded in Alabama. The native species (S. indicus and S. jacquemontii) overlap morphologically with non-native species (S. fertilis and S. pyramidalis, respectively), leading to questions of whether the tall individuals belonged to the native species or were unnoticed invaders.  Preliminary results from chloroplast data (rpl32) show that although S. indicus is morphologically distinct, S. indicus and S. jacquemontii are genetically indistinguishable. Samples belonging to the S. jacquemontii-S. pyramidalis morphological cluster were identified genetically as S. pyramidalis, supporting cryptic invasion. A reduced representation genomic dataset will be generated by sequencing inter-simple sequence repeat regions (ISSRseq) to determine (1) if S. indicus and S. jacquemontii are distinct evolutionary units and (2) population structure and gene flow between species.