Previous plant molecular baraminology studies included analysis of the chloroplast genome alone (Liliales), as well as comparison to hybridization data (Cucurbitaceae). The present study includes the analysis of chloroplast genomes and mitochondrial genomes in various species of myrtles (Myrtales).

Myrtales is an economically important order of rosids comprising nine families, 380 genera, and approximately 13,000 species. Compared to other angiosperms with a single phloem layer, Myrtales uniquely possesses phloem tissue on both sides of its xylem vessels.

The chloroplast genomes of 306 Myrtales and six Cucurbita species were downloaded from NCBI and aligned using the MAFFT sequence alignment software. Using ward.D2 clustering, 15 statistically significant clusters were found (p<0.05), with at least three species (Melastoma, Syzygium, Angophora + Corymbia + Eucalyptus, Phyllagathis, Lagerstroemia, Sonneratia, Sonerila, Trapa, Circaea + Ludwigia, Chamaenerion, Epilobium, Oenothera, and four mixed groups). Oenothera curtiflora, lindheimeri, and villaricae contained a genomic inversion encompassing the genes rbcL, atpB, atpE, rps4, psaA–D, petN, rpoB, ropC1, rpoC2, rps2, atpI, atpH, atpF, atpA, psbI, and psbK. This inversion likely occurred before seven other Oenothera species split off and formed a monobaramin.

The cytochrome-c oxidase subunit I (COI) gene sequence was extracted for 18 Myrtales species having mitochondrial genomes, with Brassica napus (rapeseed) as an outlier. These sequences were aligned and clustered. Three statistically significant clusters were identified, including the genera Oenothera (O. biennis, elata and villaricae), Eucalyptus, and Melastoma. These three genera were also found by the chloroplast analysis, meaning that with two separate lines of evidence, these may indeed be real plant holobaramins.