Mycetomoellerius kempfi

Mycetomoellerius kempfi
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Mycetomoellerius
Species:	M. kempfi
Binomial name
Mycetomoellerius kempfi (Fowler, 1982) Specimen labels

Fowler (1982) commented briefly that nests of M. kempfi consist of small tumulus of excavated soil, with one entrance and that he observed workers foraging on fresh leguminous vegetation. (Mayhe-Nunes and Brandão 2005)

Identification

A member of the iheringi species group. Mayhe-Nunes and Brandão (2005) - This species resembles Mycetomoellerius iheringi (see discussion), as reported by Fowler (1982), but good distinctive characters are the lobes on antennal scapes pointing outwards and the abundant, long and flexuous pilosity of the body. Kempf labeled specimens that belong to this taxon with a name meaning a Trachymyrmex (the genus it was originally described as belonging to) with long hairs in Latin. Indeed, all specimens of M. kempfi show long, flexuous decumbent hairs all over the body as mentioned above.

In comparison with type-locality samples, some Sao Paulo specimens have the projections on the declivous face of mesonotum and dorsum of petiole vestigial or absent.

Santos et al. (2025) provide a multi-entry interactive key based on the xper3 platform which contains 27 characters and, as terminals, 30 species of Mycetomoellerius, representing almost all described species except for Mycetomoellerius echinus, Mycetomoellerius gaigei and Mycetomoellerius guianensis, which are excluded due to lack of clear information or available specimens for study.

Keys including this Species

• Key to Trachymyrmex iheringi species group workers

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -17.45404° to -31.648611°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Neotropical Region: Argentina, Brazil, Paraguay (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Explore Fungus Growing  For additional details see Fungus growing ants. A handful of ant species (approx. 275 out of the known 15,000 species) have developed the ability to cultivate fungus within their nests. In most species the fungus is used as the sole food source for the larvae and is an important resource for the adults as well. Additionally, in a limited number of cases, the fungus is used to construct part of the nest structure but is not as a food source. These fungus-feeding species are limited to North and South America, extending from the pine barrens of New Jersey, United States, in the north (Trachymyrmex septentrionalis) to the cold deserts in Argentina in the south (several species of Acromyrmex). Species that use fungi in nest construction are known from Europe and Africa (a few species in the genera Crematogaster, Lasius). The details of fungal cultivation are rich and complex. First, a wide variety of materials are used as substrate for fungus cultivating. The so-called lower genera include species that prefer dead vegetation, seeds, flowers, fruits, insect corpses, and feces, which are collected in the vicinity of their nests. The higher genera include non leaf-cutting species that collect mostly fallen leaflets, fruit, and flowers, as well as the leafcutters that collect fresh leaves from shrubs and trees. Second, while the majority of fungi that are farmed by fungus-feeding ants belong to the family Lepiotaceae, mostly the genera Leucoagaricus and Leucocoprinus, other fungi are also involved. Some species utilise fungi in the family Tricholomataceae while a few others cultivate yeast. The fungi used by the higher genera no longer produce spores. Their fungi produce nutritious and swollen hyphal tips (gongylidia) that grow in bundles called staphylae, to specifically feed the ants. Finally, colony size varies tremendously among these ants. Lower taxa mostly live in inconspicuous nests with 100–1000 individuals and relatively small fungus gardens. Higher taxa, in contrast, live in colonies made of 5–10 million ants that live and work within hundreds of interconnected fungus-bearing chambers in huge subterranean nests. Some colonies are so large, they can be seen from satellite photos, measuring up to 600 m3. Based on these habits, and taking phylogenetic information into consideration, these ants can be divided into six biologically distinct agricultural systems (with a list of genera involved in each category): Nest Construction A limited number of species that use fungi in the construction of their nests. some Crematogaster some Lasius Lower Agriculture Practiced by species in the majority of fungus-feeding genera, including those thought to retain more primitive features, which cultivate a wide range of fungal species in the tribe Leucocoprineae. some Apterostigma Cyatta (1 species) some Cyphomyrmex Kalathomyrmex (1 species) Mycocepurus (6 species) Myrmicocrypta (31 species) Mycetarotes (4 species) Mycetosoritis (2 species) Mycetophylax (21 species) Paramycetophylax (1 species) Xerolitor (1 species) Coral Fungus Agriculture Practiced by species in the Apterostigma pilosum species-group, which cultivate fungi within the Pterulaceae. some Apterostigma Yeast Agriculture Practiced by species within the Cyphomyrmex rimosus species-group, which cultivate a distinct clade of leucocoprineaceous fungi derived from the lower attine fungi. some Cyphomyrmex Generalized Higher Agriculture Practiced by species in several genera of non-leaf-cutting "higher attine" ants, which cultivate a distinct clade of leucocoprineaceous fungi separately derived from the lower attine fungi. Mycetomoellerius (33 species) Paratrachymyrmex (9 species) Sericomyrmex (11 species) Trachymyrmex (9 species) Leaf-Cutter Agriculture A subdivision of higher attine agriculture practiced by species within several ecologically dominant genera, which cultivate a single highly derived species of higher attine fungus. Acromyrmex (51 species) Amoimyrmex (3 species) Atta (20 species) Note that the farming habits of Mycetagroicus (4 species) are unknown. Also, while species of Pseudoatta (2 species) are closely related to the fungus-feeding genus Acromyrmex, they are social parasites, living in the nests of their hosts and are not actively involved in fungus growing. ‎

Phylogeny

Mycetomoellerius	Mycetomoellerius urichii Mycetomoellerius papulatus Mycetomoellerius papulatus Mycetomoellerius holmgreni Mycetomoellerius cirratus Mycetomoellerius kempfi Mycetomoellerius iheringi Mycetomoellerius sp. near cirratus
	Mycetomoellerius ruthae Mycetomoellerius jamaicensis Mycetomoellerius atlanticus Mycetomoellerius near haytianus Mycetomoellerius opulentus Mycetomoellerius dichrous Mycetomoellerius relictus Mycetomoellerius turrifex Mycetomoellerius zeteki

Based on Micolino et al., 2020 (selected species only).

Nomenclature

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

• kempfi. Trachymyrmex kempfi Fowler, 1982: 70, figs. 1-3 (w.) PARAGUAY.
  • Combination in Mycetomoellerius: Solomon et al., 2019: 948.
  • See also: Mayhé-Nunes & Brandão, 2005: 290.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

Worker

Mayhe-Nunes and Brandão (2005) - TL 3.8-4.2; HL 1.02-1.14; HW 0.95-1.03; IFW 0.65-0.68; ScL 0.73-0.89; TrL 1.49-1.67; Hfl 1.35-1.42. Reddish yellow to reddish brown, with darker postpetiole and gaster in some specimens. Integuement fine and indistinctly shagreened, opaque. Body and appendages clothed with moderately long and oblique to decumbent hairs; scarce strongly curved short hairs confined to some parts of postpetiole and gaster.

Head in full face view little longer than broad (CI 95). Mandible smooth and shining except laterally on base, where it is finely transversely striate, and near the masticatory margin, which bears the apical, and 6 regularly developed teeth. Frontal lobe sub-triangular, moderately expanded laterad (FLI66); anterior border evenly concave; posterior border slightly convex. Frontal carina diverging cuadad, fading out a little before the apex of scrobe. Front and vertex without longitudinal rugulae, with minute isolated piligerous tubercles. Posterior third of antennal scrobe vestigially delimited. Supraocular projection vestigial. Occipital corner rounded in full-face view, with many small piligerous tubercles. Occiput slightly notched in middle. Occipital tooth developed as a stout spine-like projection rather smooth. Inferior occipital corner indistinctly emarginated with weak carina. Eye almost flat, no more than 14 facets in a row across the greatest diameter. Antennal scape slighty surpassing the occipital corner, when laid back over the head as much as possible; basal lobe perpendicularly enlarged, its outer projection bigger than the internal ones, outwards directed when the scape is lodged in the scrobe; anterior surface surmounted by small tubercles.

Alitrunk. Pronotum with an indistinct humeral angle; antero-inferior corner armed with a triangular and flattened spine-like projection; lateral spines moderately long; median projections as two small microtuberculated spines. Mesonotum with the first pair of projections a little stouter and longer than pronotal lateral spines; second pair very low, formed by a small and crenulated longitudinal ridge, sometimes vestigial; third pair vestigial or absent. Mesopleura covered with hairs; acute triangular projection on superior border of katepisternum. Alitrunk weakly constricted dorso-laterally at the shallowly impressed metanotal groove. Basal face of propodeum narrow, laterally delimited by a row of small teeth; propodeal spines longer and slender than promesonotal projections.

Waist and gaster. Petiole shortly pedunculated, the node proper as long as broad, with one or two pairs of minute dorsal teeth; subpetiolar process vestigial. Postpetiole slightly broader than long, shallowly excavate above; postero-dorsal border straight; posterolateral corners without projections. Gaster opaque with minute piligerous tubercles randomly distributed in the tergum 1.

Type Material

Mayhe-Nunes and Brandão (2005) - Workers, holotype and 18 paratypes. Paraguay, Nueva Assuncion: Teniente Enciso [21° 00'S 61° 00' W] (Museum of Comparative Zoology, National Museum of Natural History; Los Angeles County Museum of Natural History; not examined).

Alex Wild collected a sample in Paraguay, compared it with types (deposited in LACM, and not as stated by Fowler although we are not sure whether the collections mentioned by Fowler keep other types) and kindly sent us two workers for deposit in the MZSP. Afterwards, we found an undetermined sample in the MZSP that we recognize as T. kempfi, with a handwritten label by Kempf with very similar data to the type material: Paraguay, Tte. Enciso 1975 HF xiv, H. Fowler, # 13414; although they do not belong to the type series, probably belong to the series used by Fowler in the original description.

References

• Fowler, H. G. 1982a. A new species of Trachymyrmex fungus-growing ant (Hymenoptera: Myrmicinae: Attini) from Paraguay. J. N. Y. Entomol. Soc. 90: 70-73 (page 70, figs. 1-3 worker described)
• Mayhé-Nunes, A. J. and Brandão, C. R. F. 2005. Revisionary studies on the attine ant genus Trachymyrmex Forel. Part 2: the Iheringi group (Hymenoptera: Formicidae). Sociobiology. 45(2):271-305. (page 290, figs. 29-32 worker described)
• Santos, C.D.A.D., Chaul, J.C.M., Serrao, J.E. 2025. Taxonomic contributions to Mycetomoellerius Solomon et al., 2019 (Hymenoptera: Formicidae: Myrmicinae): description of two new species and a key for the genus. Zootaxa 5569(1), 93–118 (doi:10.11646/zootaxa.5569.1.3)
• Solomon, S.E., Rabeling, C., Sosa-Calvo, J., Lopes, C.T., Rodrigues, A., Vasconcelos, H.L., Bacci Jr, M., Mueller, U.G., Schultz, T.R. 2019. The molecular phylogenetics of Trachymyrmex Forel ants and their fungal cultivars provide insights into the origin and coevolutionary history of ‘higher-attine’ ant agriculture. Systematic Entomology 44: 939-956 (doi:10.1111/syen.12370).
• Tibcherani, M., Aranda, R., Mello, R.L. 2020. Time to go home: The temporal threshold in the regeneration of the ant community in the Brazilian savanna. Applied Soil Ecology 150, 103451 (doi:10.1016/j.apsoil.2019.103451).

References based on Global Ant Biodiversity Informatics

• Brandao, C.R.F. 1991. Adendos ao catalogo abreviado das formigas da regiao neotropical (Hymenoptera: Formicidae). Rev. Bras. Entomol. 35: 319-412.
• Drose W., L. R. Podgaiski, A. Cavalleri, R. M. Feitosa, and M. S. Mendonca. 2017. Ground-dwelling and vegetation ant fauna in southern Brazilian grasslands. Sociobiology 64(4): 381-392.
• Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
• Fowler H. G. 1982. A new species of Trachymyrmex fungus-growing ant (Hymenoptera: Myrmicinae: Attini) from Paraguay. J. N. Y. Entomol. Soc. 90: 70-73.
• Mayhé-Nunes A. J., and C. R. F. Brandão. 2005. Revisionary studies on the attine ant genus Trachymyrmex Forel. Part 2: the Iheringi group (Hymenoptera: Formicidae). Sociobiology 45(2): 271-305.
• Solomon S. E., C. Rabeling, J. Sosa-Calvo, C. Lopes, A. Rodrigues, H. L. Vasconcelos, M. Bacci, U. G. Mueller, and T. R. Schultz. 2019. The molecular phylogenetics of Trachymyrmex Forel ants and their fungal cultivars provide insights into the origin and coevolutionary history of ‘higher-attine’ ant agriculture. Systematic Entomology 44: 939–956.