Crematogaster clariventris

Crematogaster clariventris is a territorially dominant arboreal species that constructs very hard carton nests. Noting that workers cut off leaves from different plant species while building or repairing their nests, Dejean et al. (2023) asked if there was a correlation. They conducted scanning electron microscopic observations of nest walls that revealed the presence of fungal mycelia. As the presence of filamentous Ascomycota has been shown on arboreal ant nests worldwide, they used a metabarcoding approach and, indeed, noted the presence of Operational Taxonomic Unit (OTU) Cre_006041 of the Capnodiales known to reinforce large nests of an unidentified African Crematogaster. This OTU was also recorded in the workers' bodies. At a very low level, we also noted OTU Cre_320021 of the Chaetothyriales known for their relationships with the African plant-ant species C. margaritae. Therefore, by cutting leaves and growing fungus, C. clariventris illustrates a case of convergent evolution with higher New World leaf-cutting, fungus-growing Attina of the genera Acromyrmex, Amoimyrmex and Atta. However, there are notable differences. Leaf-cutting Attina cultivate Agaricaceae (Basidiomycota) for food, whereas C. clariventris uses Capnodiales to reinforce their nests (i.e., after the mycelium died, the hyphae's cell walls remained sturdy forming a natural composite material), have a distinct geographical origin (i.e., New World vs. Old World) and belong to a distinct ant tribe in the subfamily Myrmicinae (i.e., Attini vs. Crematogastrini). Furthermore, leaf-cutting Attina evolved an efficacious means of cutting leaves by using their mandibles asymmetrically, whereas C. clariventris workers, typically, use their mandibles symmetrically.

Distribution based on Regional Taxon Lists
Afrotropical Region: Cameroun, Congo, Guinea, Kenya, Uganda.

Nomenclature

 * . Crematogaster buchneri subsp. clariventris Mayr, 1895: 139 (w.) CONGO.
 * Type-material: syntype workers (number not stated).
 * Type-locality: Congo (“Loango Coast”): (no further data) (H. Brauns).
 * Type-depository: NHMW.
 * Forel, 1911e: 271 (q.).
 * Combination in C. (Atopogyne): Wheeler, W.M. 1922a: 854.
 * Subspecies of buchneri: Mayr, 1896: 242; Forel, 1911e: 271; Forel, 1912j: 180; Forel, 1913c: 352; Forel, 1913h: 351; Menozzi, 1933a: 103.
 * Status as species: Wheeler, W.M. 1922a: 854; Emery, 1922e: 155; Santschi, 1930a: 65; Santschi, 1933b: 100; Santschi, 1935a: 263; Santschi, 1937b: 99; Santschi, 1939c: 8; Bernard, 1953b: 234; Bolton, 1995b: 150; Hita Garcia, et al. 2013: 210.
 * Distribution: Cameroon, Congo, Democratic Republic of Congo, Ghana, Guinea, Ivory Coast, Kenya, Liberia, Nigeria, Uganda.
 * Current subspecies: nominal plus biimpressa.

References based on Global Ant Biodiversity Informatics

 * Belshaw R., and B. Bolton. 1994. A survey of the leaf litter ant fauna in Ghana, West Africa (Hymenoptera: Formicidae). Journal of Hymenoptera Research 3: 5-16.
 * Belshaw R., and B. Bolton. 1994. A survey of the leaf litter ant fauna in Ghana, West Africa (Hymenoptera: Formicidae). Journal of Hymenoptera Research. 3: 5-16.
 * Bernard F. 1953. La réserve naturelle intégrale du Mt Nimba. XI. Hyménoptères Formicidae. Mémoires de l'Institut Français d'Afrique Noire 19: 165-270.
 * Dejean A., F. Azemar, R. Cereghino, M. Leponce, B. Corbara, J. Orivel, and A. Compin. 2015. The dynamics of ant mosaics in tropical rainforests characterized using the SelfOrganizing Map algorithm. Insect Science doi: 10.1111/1744-7917.12208
 * Dufour B. 1991. Place et importance des différentes espèces d'insectes dans l'écologie du CSSV (Cocoa Swollen Shoot Virus) au Togo). Café Cacao Thé 35(3): 197-204.
 * Forel A. 1911. Die Ameisen des K. Zoologischen Museums in München. Sitzungsber. Math.-Phys. Kl. K. Bayer. Akad. Wiss. Münch. 11: 249-303.
 * Forel A. 1913. Fourmis de Nigérie. Revue Zoologique Africaine (Brussels) 2: 352-353.
 * Forel A. 1913. Quelques fourmis du Musée du Congo Belge (1). Annales de la Société Entomologique de Belgique 57: 347-359.
 * Garcia F.H., Wiesel E. and Fischer G. 2013.The Ants of Kenya (Hymenoptera: Formicidae)Faunal Overview, First Species Checklist, Bibliography, Accounts for All Genera, and Discussion on Taxonomy and Zoogeography. Journal of East African Natural History, 101(2): 127-222
 * IZIKO South Africa Museum Collection
 * Majer J. D. 1976. The ant mosaic in Ghana cocoa farms: further structural considerations. Journal of Applied Ecology 13: 145-155.
 * Majer J. D. 1976. The influence of ants and ant manipulation on the cocoa farm fauna. The journal of Applied Ecology 13(1): 157-175.
 * Medler J. T. 1980: Insects of Nigeria - Check list and bibliography. Mem. Amer. Ent. Inst. 30: i-vii, 1-919.
 * Santschi F. 1935. Hymenoptera. I. Formicidae. Mission Scientifique de l'Omo 2: 255-277.
 * Tadu Z., C. Djieto-Lordon, R. Babin, Yede, E. B. Messop-Youbi, and A. Fomena. 2013. Influence of insecticide treatment on ant diversity in tropical agroforestry system: some aspect of the recolonization process. International Journal of Biodiversity and Conservation 5(12): 832-844.
 * Taylor B. 1979. Ants of the Nigerian Forest Zone (Hymenoptera: Formicidae). III. Myrmicinae (Cardiocondylini to Meranoplini). Cocoa Research Institute of Nigeria Research Bulletin 6: 1-65.
 * Wheeler W. M. 1922. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. VIII. A synonymic list of the ants of the Ethiopian region. Bulletin of the American Museum of Natural History 45: 711-1004