Large giant mealworms are 40-60mm long. Giant mealworms (Zophobas morio), are more resilient and easier to maintain plus their larger size means the ratio of indigestible chiton in the outer skeleton to body mass is a lot lower making them easier for reptiles and amphibians to digest. The giants mealworms also tend to be a little more omnivorous than the common mealworm, which should improve their nutritional value. The key to feeding any type of mealworms is moderation. They can be fed regularly but only in small quantities at each feeding session, e.g. 2-3 apporpriately-sized mealworms per feed. Any more than this and the excess chitin can lead to regurgitation.