Mycetomoellerius atlanticus

Mycetomoellerius atlanticus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Mycetomoellerius
Species:	M. atlanticus
Binomial name
Mycetomoellerius atlanticus (Mayhé-Nunes & Brandão, 2007)

This is the most common Mycetomoellerius in the Restinga da Marambaia. The type material consisted of a collection from pitfall traps, but we were not able to find any nests. Samples from other localities were also exclusively collected near the beach at the Brazilian coast, but unfortunately the labels do not contain further biological data. Workers of M. atlanticus may build their nests in sandy soils in the coastal dunes.

Identification

A member of the jamaicensis species group. Mayhé-Nunes & Brandão (2007) - Workers of this species may be confounded with those of Mycetomoellerius zeteki, but can be separated because M. atlanticus workers lack conspicuous teeth on the anterior lateral margin of the frontal lobes, and also by the longer antennal scapes, shorter propodeal spines, sagital keel on sternum I of gaster and lighter color. They differ from Mycetomoellerius jamaicensis and Mycetomoellerius ixyodus by the projecting midpronotal tooth, which bears much shorter anterior mesonotal projections. From Mycetomoellerius haytianus workers of M. atlanticus can be distinguished by coarse spatulate hairs all over the body and the lighter coloration. Mycetomoellerius isthmicus lacks the inferior pronotal projection and has the lateral pronotal projections shorter than mesonotal anterior ones.

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.

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -19.17291° to -23.03333333°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (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. ‎

Castes

Known only from the worker caste.

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.

• atlanticus. Trachymyrmedx atlanticus Mayhé-Nunes & Brandão, 2007: 5, figs. 1-4, 30 (w.) BRAZIL.
  • Combination in Mycetomoellerius: Solomon et al., 2019: 948.

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

Description

Worker

(n = 9). TL 5.2 (4.3–5.6); DHL 1.51 (1.31–1.58); HW 1.39 (1.11–1.47); IFW 0.89 (0.78–0.93); ScL 1.14 (1.00–1.24); HWL 0.95 (0.71–1.09); MeL 2.02 (1.78–2.13); PL 0.37 (0.27–0.42); PPL 0.49 (0.40–0.56); GL 1.37 (1.18–1.44); HfL 2.14 (1.78–2.22).

Light yellow to yellowish-brown, with darker spots on the head dorsum, mesosoma and gaster, giving to overall body a smudge appearance in lighter specimens; darker funiculus, tarsi and shiny mandibles. Integument opaque and finely granulose. Pilosity: short, bristly spatulate dark hairs confined to body projections, strongly curved or hook-like hairs on other parts of the body.

Figs. 1-4

Head in full face view (Fig. 1) a little longer than broad to as long as broad (DCI average 93; 90–99). Outer border of mandible feebly sinuous; masticatory margin with two apical and five teeth, with a diastema between the subapical and third teeth. Clypeus median apron without projections. Frontal area impressed. Frontal lobe semicircular, moderately expanded (FLI average 63; 62–67), with smooth free border, lacking prominent denticles on the slightly crenulate antero-lateral border. Frontal carina moderately diverging caudad, reaching the antennal scrobe posterior end in a small tooth at the posterior margin of head; preocular carina posteriorly ending in the posterior margin as a tubercle larger than the frontal carina projection. Occipital spine almost as long as preocular carina projection. Supraocular projection indistinct. Inferior corner of occiput, in side view, with a small blunt spine. Eye faintly convex, not surpassing the head lateral border, with 14 facets in a row across the greatest diameter. Antennal scape, when lodged in the scrobe, projecting beyond the tip of the preocular carina projection; gradually thickened toward apex, covered with small piligerous tubercles.

Mesosoma (Figs. 1, 2). Pronotal dorsum faintly marginate in front and on sides; antero-inferior corner with a strong and blunt flattened spine; inferior margin smooth; median pronotal tooth tip truncate, projected above the tip of the longer lateral pronotal spines, which points outwards from the pronotum, in frontal view. Anterior pair of mesonotal spines a little longer and stouter than lateral pronotal ones, directed upwards; the second and third pairs gradually smaller, almost tooth-like. Anterior margin of katepisternum smooth, with a minute tooth on the superior third. Metanotal constriction shallowly impressed. Basal face of propodeum laterally marginate by a row of 3–4 denticles on each side; propodeal spines shorter than the distance between their inner bases. Hind femora longer than mesosoma length.

Waist and gaster (Figs. 2–4). Dorsum of petiolar node with two pairs of minute spines, the sides parallel in dorsal view, with a series of lateral denticles; sternum without sagital keel. Postpetiole broader than long in dorsal view, broader behind than in front, and shallowly impressed dorsally, with concave postero-dorsal border. Gaster, when seen from above, suboval. Tergum I (=abdominal tergum IV) with straight lateral faces separated from the dorsal face by a longitudinal row of piligerous tubercles on each side; anterior two thirds of dorsum with three glabrous shallow longitudinal furrows separated by a pair of piligerous tubercles rows. Sternum I with a small anterior sagital keel.

Type Material

Holotype worker: BRAZIL, Rio de Janeiro: Restinga da Marambaia [23° 02’ S, 43° 36’ W], 15.iii.2005, A. B. Vargas col., pitfall trap # P2G3S16 (deposited in Instituto de Biologia Universidade Federal Rural do Rio de Janeiro). Paratype workers: same data as holotype, pitfalls # P2G3S16 (2 workers deposited in CECL, 3 deposited in Museu de Zoologia da Universidade de Sao Paulo), 2 workers # P3G2S6 (deposited in CECL), 2 workers # P2G2S14 (deposited in MZSP).

Etymology

This species shows a distribution restricted to the Atlantic forest domain, and hence its name.

References

• Mayhé-Nunes, A.J., Brandão, C.R.F. 2007. Revisionary studies on the attine ant genus Trachymyrmex Forel. Part 3: The Jamaicensis group (Hymenoptera: Formicidae). Zootaxa. 1444:1-21 (doi:10.11646/zootaxa.1444.1.1).
• 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).

References based on Global Ant Biodiversity Informatics

• Mayhe-Nunes A. J., and C. R. F. Brandao. 2007. Revisionary studies on the attine ant genus Trachymyrmex Forel. Part 3: The Jamaicensis group (Hymenoptera: Formicidae). Zootaxa 1444: 1-21.
• Nascimento Santos M., J. H. C. Delabie, and J. M. Queiroz. 2019. Biodiversity conservation in urban parks: a study of ground-dwelling ants (Hymenoptera: Formicidae) in Rio de Janeiro City. Urban Ecosystems https://doi.org/10.1007/s11252-019-00872-8
• 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.