Meeting Abstract
Mantis shrimp use a latch-mediated spring actuation (LaMSA) mechanism in their raptorial appendages to produce powerful strikes for resource acquisition and defense. Previous research on the mantis shrimp strike, including kinematics and appendage morphology, has focused exclusively on the adults (3-30 cm total length). However, mantis shrimp first exhibit striking behavior during their larval stages (~3 mm total length). At this size, mathematical models suggest that spring driven motion may not be an effective way of actuating the mantis shrimp strike. Understanding the larval mantis shrimp strike allows us to address major questions regarding the scaling and development of LaMSA systems. Here we describe the larval mantis shrimp strike in Gonodactylaceus falcatus, including raptorial appendage development, morphology, and kinematics. We raised G. falcatus collected as eggs in Honolulu, Hawaii to their seventh larval stage. Using light and scanning electron microscopy we show that larval G. falcatus possess the saddle and meral-v as early as their fourth larval stage. Using a custom designed apparatus, we captured high speed video of strikes from fourth and fifth stage larvae. Larval mantis shrimp achieved, on average, rotational accelerations of 6.5×105 ± 5.1×105 rad/s2 with an angular velocity of 350.1±159 rad/s (12 animals, 26 strikes). When comparing strike kinematics from larvae to various adult mantis shrimp species, we find larvae achieve similar angular accelerations as adult mantis shrimp. Establishing the development of the raptorial appendage and strike kinematics in larval mantis shrimp offers insights on the development of LaMSA morphology, and how size may limit LaMSA mechanisms.
