Keller, R. A. 2000. Cladistics of the tribe Ectatommini (Hymenoptera: Formicidae): a reappraisal. Insect Systematics and Evolution 31:59-69. PDF

Keller, R.; Agosti, D. 2002. The phylogeny of Formicidae (Hymenoptera): evaluation of key characters and alternative hypotheses of relationship. [Abstract.]. P. 157 in: Billen, J. P. J. 2002. XIV International Congress of IUSSI. The Golden Jubilee Proceedings. 27 July - 3 August 2002, Hokkaido University, Sapporo, Japan. Sapporo: XIV International Congress of IUSSI, 233 pp.

Keller, R. A. 2011. A phylogenetic analysis of ant morphology (Hymenoptera: Formicidae) with special reference to the poneromorph subfamilies. Bulletin of the American Museum of Natural History 355:1-90. PDF

Keller, R. A.; Peeters, C.; Beldade, P. 2014. Evolution of thorax architecture in ant castes highlights trade-off between flight and ground behaviors. eLife 2014 (3):19pp. e01539. 10.7554/eLife.01539.001 PDF

Khalife, A.; Keller, R. A.; Billen, J.; Hita Garcia, F.; Economo, E. P.; Peeters, C. 2018. Skeletomuscular adaptations of head and legs of Melissotarsus ants for tunnelling through living wood. Frontiers in Zoology 15 (30):11 pp. 10.1186/s12983-018-0277-6 PDF

Notes: Melissotarsus anatomy, morphological adaptations

Richter, A.; Keller, R. A.; Rosumek, F. B.; Economo, E. P.; Hita Garcia, F.; Beutel, R. G. 2019. The cephalic anatomy of workers of the ant species Wasmannia affinis (Formicidae, Hymenoptera, Insecta) and its evolutionary implications. Arthropod Structure & Development 49:26-49. 10.1016/j.asd.2019-02-002 PDF

Notes: Cranial anatomy of Formicidae, with Wasmannia as exemplar.

Beutel, R. G.; Richter, A.; Keller, R. A.; Hita Garcia, F.; Matsumura, Y.; Economo, E. P.; Gorb, S. N. 2020. Distal leg structures of the Aculeata (Hymenoptera): A comparative evolutionary study of Sceliphron (Sphecidae) and Formica (Formicidae). Journal of Morphology 2020:1-17. [online early] 10.1002/jmor.21133 PDF

Richter, A.; Hita Garcia, F.; Keller, R. A.; Billen, J.; Economo, E. P.; Beutel, R. G. 2020. Comparative analysis of worker head anatomy of Formica and Brachyponera (Hymenoptera: Formicidae). Arthropod Systematics and Phylogeny 78:133-170. 10.26049/ASP78-1-2020-06 PDF

Richter, A.; Hita Garcia, F.; Keller, R. A.; Billen, J.; Katzke, J.; Boudinot, B. E.; Economo, E. P.; Beutel, R. G. 2021. The head anatomy of Protanilla lini (Hymenoptera: Formicidae: Leptanillinae), with a hypothesis of their mandibular movement. Myrmecological News 31:85-114. 10.25849/myrmecol.news_031:85 PDF

Notes: Head anatomy, Protanilla

Boudinot, B. E.; Richter, A.; Katzke, J.; Chaul, J. C. M.; Keller, R. A.; Economo, E. P.; Beutel, R. G.; Yamamoto, S. 2022. Evidence for the evolution of eusociality in stem ants and a systematic revision of †Gerontoformica (Hymenoptera: Formicidae). Zoological Journal of the Linnean Society 195:1355-1389. 10.1093/zoolinnean/zlab097/6523228 PDF

Aibekova, L.; Boudinot, B. E.; Beutel, R. G.; Richter, A.; Keller, R. A.; Hita Garcia, F.; Economo, E. P. 2022. The skeletomuscular system of the mesosoma of Formica rufa workers (Hymenoptera: Formicidae). Insect Systematics and Diversity 6 (2): 2:1-26. 10.1093/isd/ixac002 PDF

Gómez, K.; Csősz, S.; Jégh, T.; Keller, R. A. 2024. Aenictus brutus sp. nov., a new species of the army ants (Hymenoptera: Formicidae: Dorylinae) from Mount Nimba Strict Nature Reserve Forest (Liberia). Belgian Journal of Entomology 148:1-9. PDF