Abstract
The genus Amphiglena , comprising minute sabellid worms, is known for its cryptic diversity in the Mediterranean region. This study presents the first complete mitochondrial genome for the genus, corresponding to Amphiglena cf. mediterranea “clade IV” sensu Tilic et al. (2019). The mitogenome features 13 protein-coding genes, two rRNAs, and 22 tRNAs, totalling 16,401 base pairs. Notably, a novel gene order was identified, distinct from previously reported mitochondrial gene arrangement in annelids. This work provides essential genetic data for investigating mitochondrial genome evolution within Sabellidae and for understanding the evolutionary relationships within Amphiglena .