We present anatomical imaging techniques and measurements that are useful additions to the existing morphological toolbox for the identification of seven coastal grasses and one rush. Our method is simple and inexpensive and requires the removal of only one leaf, which prevents removal of plants from their habitats. This method can also be used in seasons when reproductive structures (important for current morphological ID efforts) are not present. We find significant quantitative differences in leaf width, adaxial to abaxial ratios (ADAB ratio, which we introduce as a new parameter), vascular bundle cross-sectional areas, and interveinal distances, as well as providing images for qualitative analysis of these plants’ anatomies; including differences in bundle sheath structures, fiber distributions, epidermal and cuticular properties, and chloroplast positioning.

We evaluated an assemblage of 235 plant fossil specimens from the well-known Middle Pennsylvanian Mazon Creek locality accessioned into the Paleontology Collections of the North Carolina Museum of Natural Sciences (Raleigh). The specimens are preserved as siderite nodules, common to the Mazon Creek biota. All but three of the specimens were donated by Mr. George Oliver, and were found at a quarry near Joliet in Will County, Illinois. The collection includes pteridosperms, pteridophytes, lycophytes, equisetophytes, cordaites, and specimens of unknown affinities, and includes relatively rare specimens of Codonotheca caudua and Cordaianthus ovata. Forty-four previously unidentified specimens were identified to genus or species. Sixty specimens were previously misidentified and corrections were made. This is a small but noteworthy collection that increases paleobotanical material available for researchers to access.

Phlox pilosa ssp. sangamonensis is a state-endangered and narrowly endemic taxon only found in Champaign and Piatt counties, Illinois. Here, we present evidence of natural hybridization between Phlox divaricata ssp. laphamii and P. pilosa ssp. sangamonensis. In May 2018, we collected a putative F1 hybrid of the two taxa in a sympatric population. We screened six microsatellites developed for North American Phlox species and measured eight morphological traits to test the specimen’s hybrid status. The microsatellite data were analyzed using a Bayesian clustering technique to infer genetic groupings. The eight morphological characteristics were analyzed using principal components analysis. We also measured the flowering phenology of P. divaricata ssp. laphamii and P. pilosa ssp. sangamonensis to assess the possibility of cross pollination. Bayesian clustering and the principal components analysis indicated that the sample was a Phlox divaricata ssp. laphamii × Phlox pilosa ssp. sangamonensis. There was modest phenological overlap between the two taxa, suggesting that gene flow is possible—though likely uncommon—in sympatric populations. We then discuss the effects of this hybridization on P. pilosa ssp. sangamonensis conservation and genetic composition.