First reported evidence of healing after a traumatic mandibular fracture with associated soft-tissue avulsion in the deep-sea sevengill shark (Heptranchias perlo).

This study presents the first documented case of healing in the deep-sea sharpnose sevengill shark (Heptranchias perlo), a poorly understood species in the Mediterranean Sea. A juvenile specimen that sustained a traumatic mandibular fracture with extensive soft-tissue avulsion, which likely resulted from de-hooking during a previous longline capture, was retrieved dead by a bottom trawler in the southern Adriatic Sea. Gross pathological and radiographic examinations confirmed that the injury remained isolated to the mandibular region, with no abnormalities detected in the splanchnocranium or the musculoskeletal system. Evidence of advanced healing and scar tissue formation was observed, and stomach content analysis revealed active feeding had occurred despite the injury, suggesting that severe mandibular trauma may not have impaired prey capture or consumption. The documented healing indicates that survival following severe mandibular injury and longline capture is possible in H. perlo, in contrast to the high at-vessel mortality previously recorded for this species in bottom-trawl fisheries. However, this conclusion remains tentative, and our findings highlight the need for further research into the recovery capacity of deep-sea shark species that are impacted by commercial fishing, which is crucial for informing conservation strategies and fishery management.