The Myriapoda, composed of millipedes and centipedes, is a fascinating but poorly understood branch of life, including species with a highly unusual body plan and a range of unique adaptations to their environment. Qu et al sequenced and assembled chromosomal-level genomes of two millipede species; Helicorthomorpha holstii and Trigoniulus corallinus. Unique genomic features, patterns of gene regulation, and defence systems in millipedes, not observed in other arthropods, were revealed. Both repeat content and intron size are major contributors to the observed differences in millipede genome size. Millipedes possesses a unique ozadene defensive gland unlike the venomous forcipules found in centipedes; the authors identify sets of genes associated with the ozadene that play roles in chemical defence as well as antimicrobial activity. Collectively, the analyses of millipede genomes reveal that a series of unique adaptations have occurred in this major lineage of arthropod diversity. The image shows the rusty millipede Trigoniulus corallinus (Spirobolida, left) and the orange rosary millipede Helicorthomorpha holstii (Polydesmida, right).

Image Credit: Wai Lok So