The park has a rich fauna of invertebrate animals, most of which have not been formally surveyed. Nearly every time someone undertakes a study of the park's insects or other invertebrates, exciting revelations are made. For example, in 2003, Dr. John Abbott took his University of Texas class on a field trip to Rattlesnake Springs and documented a new species of damselfly for New Mexico, called lenora's dancer. In 2005, the park sent some fireflies, also called "lightning bugs," to an expert for identification. It turned out that these insects, which are actually beetles, were a new genus for the state: Photuris.
In 2006 and 2013, a long-term survey of the park's moths was undertaken by lepidopterist Eric Metzler. Results are very preliminary, but hundreds of species have already been collected, including some that may be entirely new species. Surveys of the park's butterflies have yielded more than 100 species, including the Carlsbad agave skipper and the sandia hairstreak, the state butterfly of New Mexico. Thanks largely to the wooded riparian habitat with permanent water at Rattlesnake Springs, the park's list of damselflies and dragonflies is well over 60 species and includes such picturesque names as the saffron-winged meadowhawk (a dragonfly) and the desert firetail (a damselfly).
The park's underground environments harbor intriguing invertebrate wildlife as well. There are three species of cave (or camel) crickets known in Carlsbad Caverns National Park. These cricket-like insects have rounded backs and are nocturnal. Many cave crickets live in the front parts of caves only to leave at night to forage. Their diet consists of small insects, microbes, possibly algae or fungi, and each other. A number of other creatures, in turn, feed on cave crickets including bats, raccoons, and ringtails. Cave crickets, their eggs and droppings are important food sources for other cave organisms.
The three known cricket species from the park are Ceuthophilus carlsbadensis, C. longipes and C. conicaudus. As with many insects, these animals have not been given common names.
Ceuthophilus carlsbadensis is found in many caves throughout New Mexico and Texas and is very common in Carlsbad Cavern. This cricket actually shows very little adaptation for living in caves and tends to live in food-rich areas, such as cave rooms with bat guano. On the other hand, Ceuthophilus longipes (known from numerous park caves) is more cave-adapted and is found in food-poor areas. C. longipes is smaller and lighter in color and has longer legs and antennae than C. carlsbadensis. The third species, Ceuthophilus conicaudus, falls between the other two species in cave adaptation traits. It is only found sparsely in Carlsbad Cavern, but is the dominant cave cricket in a few other park caves.
Other invertebrates found in the caves include isopods, troglophilic beetles, millipedes, centipedes, various spiders, and primitive creatures related to bristletails and silverfish.
The park's preliminary insect list is constantly being expanded.