Superworms, a mealworm-like form of beetle larva commonly used as pet food, are efficient cleaners of skeletons, according to a study published in PLOS One by Fatemeh Rastekar of Ferdowsi University of Mashhad, Iran, and colleagues.

Clean animal skeletons are an invaluable resource for scientific research and education. Numerous methods exist for cleaning skeletons, including burial, enzymatic digestion, chemical treatments and the use of dermestid beetles, and each has its own drawbacks, most notably the risk of damage to bones or the risk of hazardous materials harming people. In this study, Rastekar and colleagues investigate the utility of “superworm” beetle larvae for cleaning skeletons.

Testing superworms on varied specimens

The researchers introduced varied numbers of superworms to eight enclosed animal specimens, ranging in size from a 9-gram Egyptian rousette to a 4.2-kilogram wolf. Over a period of hours to days, the larvae efficiently removed the flesh from these skeletons, inside and out. The researchers found that 10–15 grams of larva per gram of animal specimen minimized cleaning time while also avoiding damage to the bones. At this ratio, the larvae were able to clean even delicate bird skulls with no skeletal damage.

A safer museum cleaning option

The authors suggest that superworms offer a practical alternative to existing skeletal cleaning methods. Maintaining superworms involves no hazardous materials, and since they don’t metamorphose in crowded conditions, there’s much less risk of adult outbreaks compared with dermestid beetles. Superworms are also readily available from commercial breeders who commonly sell them as food for pets and livestock.

The authors state, “Our study shows that protein-rich superworms, a common pet food that is easy to maintain in colonies, can safely and efficiently clean skeletons for museum specimens. Unlike traditional chemical methods or dermestid beetle colonies, this approach preserves delicate bones, is environmentally friendly, safer for museum collections by minimizing the risk of pest infestation and makes colony maintenance much easier for museums.”