Incertogaster praecursor

†Incertogaster praecursor Temporal range: Late/Upper Miocene K Pa Eo Ol Mi Pl Sicilian amber, Italy
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Genus:	Incertogaster
Species:	†I. praecursor
Binomial name
†Incertogaster praecursor (Emery, 1891)

Boudinot et al. (2024), Note 3 - The amber-preserved males described by Emery as †Crematogaster praecursor and Radchenko & Dlussky as †Crematogaster primitiva are unlikely to be representatives of either the stem or crown of the genus Crematogaster and are incertae sedis in the Myrmicinae within †Incertogaster. Both specimens have 13-merous antennae, while all Crematogaster males examined by the lead author have antennae that are 10–12-merous (Bolton 2003, p. 286; BEB, unpubl. data). Other diagnostic features include the short scape, which is ≤ 2 × the length of the pedicel, the pedicel shape, which is globular rather than cylindrical, and the mandibles, which are reduced or otherwise vestigial; the anterodorsal position of the postpetiolar helcium on abdominal segment IV can be difficult to discern. Unfortunately, Emery did not illustrate the wings or the face of †I. praecursor, so the fossil may need to be considered unidentifiable, hence subjectively invalid, if the specimen does not resurface. †Incertogaster primitiva, on the other hand, is well illustrated; its scapes are about 4 × the length of the pedicels, and the pedicels are not swollen or globular in shape. The mesosoma of this fossil (PMJ Pa 5824) is large and the mesoscutum is impressed, as in many Crematogaster, but the long and strongly nodiform petiole also contradict placement in that genus. At present, we cannot confidently attribute †I. primitiva to any valid generic taxon.

Distribution

This taxon was described from Sicilian amber, Italy (Late/Upper Miocene).

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• †praecursor. †Crematogaster praecursor Emery, 1891a: 152, pl. 2, figs. 19-21 (m.) SICILIAN AMBER (Italy: Sicily, Oligocene).
  • Combination in †Incertogaster: Boudinot, Bock, et al. 2024: 148.
  • Status as species: Dalla Torre, 1893: 84; Handlirsch, 1907: 873; Keilbach, 1982: 275; Bolton, 1995b: 160.

References

• Boudinot, B.E., Bock, B.L., Weingardt, M., Tröger, D., Batelka, J., LI, D., Richter, A., Pohl, H., Moosdorf, O.T.D., Jandausch, K., Hammel, J.U., Beutel, R. G. 2024. Et latet et lucet: Discoveries from the Phyletisches Museum amber and copal collection in Jena, Germany. Deutsche Entomologische Zeitschrift 711, 111–176 (doi:10.3897/dez.71.112433).
• Emery, C. 1891b. Le formiche dell'ambra Siciliana nel Museo Mineralogico dell'Università di Bologna. Mem. R. Accad. Sci. Ist. Bologna (5)1:141-165 (page 152, pl. 2, figs. 19-21 male described)
• Radchenko, A.G., Dlussky, G.M. 2019. First record of the ant genus Crematogaster (Hymenoptera: Formicidae) from the Late Eocene European ambers. Annales Zoologici 69: 417-421 (DOI 10.3161/00034541ANZ2019.69.2.008).