Spider Rider

Kelly’s Field Notes

Common Name: Mantisfly, Mantidfly, Mantid lacewing, Mantispid

Order: Neuroptera

Family: Mantispidae

Genus: There are many genera of Mantisfly, I have been unable to pin down a number.

Interesting Species: (There are 15 species of mantidfly in the US, 400 worldwide (University of Florida, 2007; The Bug Lady, 2020)).

• Wasp mantisfly (Climaciella brunnea) - found throughout Canada, the U.S., and as far South as Nicaragua mimics Polistes, paper wasps (Batra, 1972).

• Lacewing mantisfly (Mantispa interrupta) - found in Central and North America, this species  has larvae that search for wolf spiders (Lycosidae) and fishing spiders (Dolomedes) egg sacs, burrow inside of them, and eat the eggs (Guriasco, 2006).

• Green mantisfly (Zeugomantispa minuta) - found throughout North, Central, and South America as well as the Carribean, it is the smallest mantisfly at 19 mm (¾ in).

• Calico mantisfly (Calomantispa venusta) - found in southern Australia and Tasmania, this species mimics wasps that are yellow and black in coloration.

Description: 

Adult mantisflies look like a cross between a praying mantis and a lacewing (convergent evolution in action!). Their heads are triangular with bulging eyes (Missouri Department of Conservation, 2025). Mantisfly adults also have an elongated prothorax (front of the thorax), making it look like they have long necks. They have raptorial front legs like mantises, but delicate, net-veined wings like lacewings. Both belong to order Neuroptera where these delicate wings are common. Adults range from 19 mm (¾ in) to 60 mm (2.3 in). The smallest is the green mantisfly (Zeugomantispa minuta) and the largest mantis fly is the wasp mantidfly (Climaciella brunnea) (Batra, 1972; Hoffman et al., 2017). Mantisfly coloration varies, most are green, tan, or brown, while others mimic wasps with black-and-yellow markings. Adults feed on other invertebrates using their grasping raptorial appendages.

Larvae go through three stages, the first are very mobile and resemble ladybug larvae (campodeiform), the other two stages are grub-like (scarabaeiform). Unlike other Neuropterans, mantisfly larvae do not produce venom. This characteristic was lost as mantisflies diverged over time (Badano et al., 2024).

Life Cycle: 

Female mantisflies lay eggs on vegetation which hatch in about a month. The wasp mantisfly (Climaciella brunnea), a spider predator, lays her eggs on long silken thread hanging from the undersides of leaves. When hunting spiders, like wolf spiders, walk by the eggs attached to the spider. Once they hatch the larvae waits by the spider’s pedicel (between the cephalothorax and the abdomen) or inside of her book lungs. Once she creates an egg sac the mantisfly larva will burrow into the spider’s eggsac and eat the eggs (Walker, 2025). When a mite or other insect travels on the back of another insect without harming it we call this behavior phoresy. Even though they eventually invade the eggsac. After the mantisfly has had its fill of eggs it will pupate, which lasts a few weeks (Bug Guide, 2024). Paleontologists found a fossil of this behavior, a larva riding a spider, that is 100 million years old (Huag et al., 2018)!

Other mantisfly larvae are parasitoids of bees, wasps, and scarab beetles or are active predators of small invertebrates (Maia-Silva et al., 2013).

Because the adults actively hunt other arthropods and spend time on flowers as sit-and-wait predators there is some evidence they may be pollinators (Boyden, 1983).

Super Powers:

• Spider Steed - larvae ride on the backs of spiders waiting for the female to create an egg sac.

• Flight - they can fly, but they are not graceful.

• Raptorial Appendage - like mantises, they can quickly grab their prey.

• Mimicry - the wasp mantisfly mimics Polistes wasps to ward off predators.

References: 

Badano, Davide, et al. "Mesozoic larva in amber reveals the venom delivery system and the palaeobiology of an ancient lineage of venomous insects (Neuroptera)." Scientific Reports 14.1 (2024): 19696.

Batra, S. W. T. “Notes on the Behavior and Ecology of the Mantispid, Climaciella Brunnea Occidentalis.” Journal of the Kansas Entomological Society, vol. 45, no. 3, 1972, pp. 334–40. JSTOR, http://www.jstor.org/stable/25082507. Accessed 8 Nov. 2025.

Mantidflies (Neuroptera:Mantispidae). University of Florida, 2007, entnemdept.ufl.edu/projex/gallery/dl/Beneficial_Arthropods_Predators/text/mantidflies.htm. Accessed 8 Nov. 2025.

Boyden, Thomas C. "Mimicry, predation and potential pollination by the mantispid, Climaciella brunnea var. instabilis (Say)(Mantispidae: Neuroptera)." Journal of the New York Entomological Society 91.4 (1983): 508-511.

Guarisco, Hank. "The wolf spider genus Gladicosa (Araneae: Lycosidae) in Kansas and egg sac predation by the mantisfly, Mantispa interrupta (Neuroptera: Mantispidae) and the wasp, Idiolispa aestivalis (Hymenoptera: Ichneumonidae) upon Gladicosa bellamyi, a new state record." Transactions of the Kansas Academy of Science 109.1 (2006): 79-82.

Haug, Joachim T., Patrick Müller, and Carolin Haug. "The ride of the parasite: a 100-million-year old mantis lacewing larva captured while mounting its spider host." Zoological Letters 4.1 (2018): 31.

“Life Cycle of Mantispidae.” Bugguide.net, 2024, bugguide.net/node/view/296580. Accessed 8 Nov. 2025.

Maia-Silva, Camila, et al. "Out with the garbage: the parasitic strategy of the mantisfly Plega hagenella mass-infesting colonies of the eusocial bee Melipona subnitida in northeastern Brazil." Naturwissenschaften 100.1 (2013): 101-105.

“Mantidflies (Mantis Flies).” Missouri Department of Conservation, 2025, mdc.mo.gov/discover-nature/field-guide/mantidflies-mantis-flies.

‌‌The Bug Lady. “Wasp Mantidfly.” College of Letters & Science Saukville Field Station, University of Wisconsin Milwaukee, 2020, uwm.edu/field-station/bug-of-the-week/wasp-mantidfly/. Accessed 8 Nov. 2025.

‌

Walker, Jim. “Wasp Mantidfly.” University of Minnesota, Department of Entomology, 2025, entomology.umn.edu/wasp-mantidfly.