Meeting Abstract
Lionfish have a passive puncture defense system in which venomous spines are embedded into a predators skin during an attack. We have previously determined that the anal and pelvic spines of the red lionfish, P. volitans, are substantially shorter than the dorsal spines, but are stiffer and can absorb more elastic energy. Here, we quantify the puncture performance of lionfish spines in buccal skin from opportunistic predators in their invasive range, and examine the performance of lionfish spines compared to hypodermic needles in porcine skin. We punctured dorsal, anal, and pelvic lionfish spines from 37 individuals (91 spines) using an Instron E1000 into three regions of buccal skin from black grouper and blacktip sharks, and we tested spines and hypodermic needles in porcine skin. We found significantly higher forces were needed to puncture shark buccal skin with lionfish dorsal, anal and pelvic spines. Spines that punctured shark skin incurred the most macro and micro damage. In comparison, lionfish spines are more effective, based on forces measured and damage incurred, at puncturing grouper buccal skin. We found that lionfish spines required higher forces, compared to two gauges (23 and 25) of hypodermic needles, to puncture porcine skin. Interestingly, lionfish pelvic spines required the greatest amount of force to puncture porcine skin, but were the most effective at puncturing grouper and shark buccal skin. We emphasize that puncture ability is greatly affected by the material the structure is embedding, and is critical to consider in puncture studies. Our data suggest that if grouper and reef sharks recognized lionfish as a consistent food source in their invasive range, their oral cavities would not be affected substantially during predation events.
