Species Pepsis menechma - Elegant Tarantula-hawk Wasp

Elegant Tarantula Hawk (coinage based on Latin name, and common name for Pepsis, though this species may not prey on tarantulas)

Pepsis menechma Lepeletier, 1845

Pepsis elegans Lepeletier, 1845

Pepsis cerberus Lucas, 1895

Pepsis novitia Banks, 1921

(...and many more)

[Note: The old names Pepsis elegans and Pepsis cerberus were synonymized under Pepsis menechma in 2005...see pg. 131 in Part 3 of Vardy(1).]

Meaning of species name menechma is a bit obscure. Lepeletier (BHL link) called it, in French, Pepsis Menechme. A French Dictionary gives, with English translations by Google:

ménechme (nominal): gémeau, jumeau (both meaning twin), sosie (doppelgänger).

This is a reference to the Roman comedy, based on a Greek original, The Menaechmi Twins. Seems that Lepeletier was referring to the similarity of menechma to the species he discussed immediately preceding, luteicornis.

Circa 20-25 mm. A female specimen from North Carolina measured 22 mm body length. Vardy (2005), p. 133, gives body lengths: 18-26 mm (male), 16-28 mm (female).

The western "cerberus" form is orange-winged (dark-bordered), with antennae entirely dark (black to dark brown).

The eastern "elegans" form is a large, blue-black wasp with orange antennae and wings black...likely mimicked by an ichneumonid wasp, Thyreodon atricolor:

Rarely encountered is a third form, once known by the name "P. novitia", with orange wings and antennae mostly dark...with a few apical segments orange.

The orange-winged "cerberus" form is recorded from Arizona, Texas, and Kansas, as well as south into Mexico.(2)

The all black "elegans" form ranges throughout the eastern and central United States (from PA west to KS, and south to FL and TX)(2). It is apparently the only Pepsis in the east (outside possible strays of P. marginata and P. saphirus from the West Indies).

Summer-early fall. June-September (North Carolina) (3).

Adults take nectar.

Females presumably deposit eggs to develop as parasitoids on large spiders, though not necessarily always tarantulas since much of this species' range lies east of that of our native tarantulas (which occur west of the Mississippi(4)). The more easterly populations of P. menenchma (i.e. "P. elegans") may prey on trapdoor spiders (cf. 2nd sentence here, from Ebeling's 1975 "Urban Entomology" from the Univ. California, Riverside, which states that Pepsis prey on "trapdoor spiders and tarantulas").

Vardy (2005) states that there are no prey records for Pepsis menechma and closely-related species.

Pepsis elegans and Pepsis cerberus (its Western counterpart) were recently synonymized under the name Pepsis menechma (by Vardy(1) in 2005).

Original description of Pepsis menechma: Histoire naturelle des insectes. Hyménoptères, volume 3, p. 481 BHL link

A species of Hogna had been noted as a host species in this reference:

Kurczewski FE, et al. New and unusual host records for North American and South American spider wasps (Hymenoptera: Pompilidae). Zootaxa. 2020 Dec 7;4891(1):zootaxa.4891.1.1. doi: 10.11646/zootaxa.4891.1.1. PMID: 33311100.

However the wasp in that publication, originally labelled Pepsis basifusca, was a misidentified Entypus species (personal communication from Dr. Kurczewski to Patrick Coin, 12/28/22).

Entypus, a related genus of large Spider Wasps. See also the ichneumonid, Thyreodon atricolor.

North Carolina State University Entomology Collection--55 pinned, including specimens from that state (dead link).

Insects of Tyson--Missouri