Cariridris

This genus has been transferred to the family Sphecidae, possibly in the (sub)family Ampulicidae.

The genus Cariridris has a long taxonomic history since it was first described as an ant (Brandão et al., 1990). Since then it has been placed in the Ampulicidae (Ohl, 2004) or treated as belonging to the Sphecidae (Dlussky and Rasnitsyn, 2003; Dlussky 2012). In 2007, new material was examined by Osten (2007), and Cariridris was returned to the Formicidae, being placed within the subfamily Myrmeciinae. However, this treatment lacked justification and no illustrations were provided to support this hypothesis. Because of this, Jouault & Nel (2021) did not consider this taxon to belong to the family Formicidae, but did not speculate on its proper placement.

Distribution
This taxon is known from.

Nomenclature

 * † [Sphecidae]
 * †Cariridris Brandão & Martins-Neto, 1990: 201. Type-species: †Cariridris bipetiolata, by original designation.

Taxonomic history

 * †Cariridris incertae sedis in Myrmeciinae: Brandão & Martins-Neto, 1990: 203; Brandão, 1991: 336; Bolton, 1994: 73; Bolton, 1995b: 23.
 * †Cariridris incertae sedis in Formicidae: Bolton, 2003: 263.
 * †Cariridris as genus: all authors.
 * †Cariridris excluded from Formicidae, incertae sedis in Hymenoptera, Aculeata: Grimaldi, et al. 1997: 7; Ward & Brady, 2003: 362.
 * †Cariridris in Myrmeciinae: Osten, 2007: 353.
 * †Cariridris excluded from Formicidae, incertae sedis in Ampulicidae: Rasnitsyn, 2002: 249; Dlussky & Rasnitsyn, 2002: 418; Dlussky, 2012: 288 (in text).
 * †Cariridris excluded from Formicidae, transferred to Sphecidae: Verhaagh, 1996: 11; Jouault & Nel, 2021: 1, 5 (exact placement not specified).

Taxonomic Notes
Dlussky & Rasnitsyn (2003) treated this genus (and its sole species) as belonging to the family Sphecidae rather than Formicidae. They state: C. bipetiolata as described and figured by Brandão et al. (1989) looks very similar to an unnamed Santana fossil kept at the American Museum Natural History (New York, New York, USA) and described as belonging to either Sphecidae (Ampulicinae) or Dryinidae (Darling, Sharkey, 1990). One of us (APR) jointly with W.J. Pulawski of the California Academy of Sciences (San Francisco, California, USA) have studied that fossil (AMNH 44108) and found it belonging to Sphecidae (probably to subfamily Ampulicinae) rather than to Formicidae. That is why we maintain here our earlier conclusion that Cariridris is a genus of Sphecidae (Rasnitsyn, 1990; Dlussky, 1998).

Osten (2007) examined additional material and returned Cariridris to the Formicidae, placing it within the subfamily Myrmeciinae. However, this treatment lacked justification and no illustrations were provided to support this hypothesis.

Dlussky (2012) followed the treatment of Dlussky & Rasnitsyn (2003) and considered this genus to be incertae sedis in Ampulicidae. Unfortunately, it appears he was unaware of the specimens examined by Osten (2007) (as he does not cite this paper) and did not comment on its placement within the Formicidae.

Jouault & Nel (2021) reviewed the available literature and concluded that this taxon does not belong within the ants, but did not provide details on its current placement.