A rare trophic interaction: Carnivory by Helicogonus princeps (Brölemann, 1902) (Diplopoda, Spirostreptida, Spirostreptidae) on the frog Physalaemus cuvieri Fitzinger, 1826 (Anura, Leptodactylidae) in Brazil

Millipedes (Diplopoda) are predominantly detritivores, and reports of carnivory in the group remain rare. Here, we describe a potential case of perimortem predation involving the frog Physalaemus cuvieri Fitzinger, 1826 (Anura, Leptodactylidae) and the millipede Helicogonus princeps (Brölemann, 1902) (Diplopoda, Spirostreptida, Spirostreptidae) in Brazil. Two adult females of H. princeps were observed tightly coiled around the frog and consuming its tissues over a 20-hour period. Although it was not possible to determine whether the frog was alive at the onset of the interaction, the behavior suggests either opportunistic predation or carrion feeding. This event represents one of the few documented instances of vertebrate consumption by millipedes and highlights the need for further investigation into the trophic ecology of this understudied group.