Mycetophylax simplex

Mycetophylax simplex
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Mycetophylax
Species:	M. simplex
Binomial name
Mycetophylax simplex (Emery, 1888) Specimen Labels

Albuquerque et al. (2005) examined the nest density of M. simplex at Rio Grande do Sul, Brazil, coastal beaches. They found average densities of 0.01 to 0.13 nests/m2 at four sites, and that nests were found near vegetation and showed a clumped distribution. They noted that the density and distribution pattern of nests seemed to be related to the availability of nesting places and foraging resources. Following this, Diehl & Diehl-Fleig (2007) described M. simplex nest architecture and colony populations.

At a Glance

• Intertidal zone

Identification

Mycetophylax simplex can be easily distinguished from other Mycetophylax by its yellow-brownish color and the unarmed propodeum.

Keys including this Species

• Key to Mycetophylax Species

Distribution

Until now the known geographic distribution of M. simplex included only the State of Rio Grande do Sul, Brazil, but we collected colonies of this species at the Isle of Florianópolis, Santa Catarina State, Brazil for the first time. Fowler (1980) recorded M. simplex in Paraguay, but as this species is currently known only along the Atlantic beaches, therefore this previous collection information should be used with care; we have not examined this material. (Klingenberg and Brandao 2009)

Latitudinal Distribution Pattern

Latitudinal Range: -27° to -33.75°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

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

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 (31 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 (56 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. ‎

Nomenclature

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

• simplex. Cyphomyrmex simplex Emery, 1888c: 361 (w.). BRAZIL.
  • Klingenberg & Brandão, 2009: 20 (q.m.).
  • Combination in C. (Mycetophylax): Emery, 1913b: 251.
  • Combination in Mycetophylax: Kempf, 1972a: 146; Sosa-Calvo et al., 2017: 9.

Type Material

Klingenberg and Brandao 2009:

Cyphomyrmex simplex (worker) Syntype Brazil, Rio Grande do Sul, São Lourenço (type specimens not localized)

Description

Klingenberg & Brandão, 2009:

Worker

Range of measurements (in mm) and indices of examined specimens (N = 36): IOD 0.83-1.03; HL 0.85-1.01; CI 96-106; SL 0.49-0.82; SI 58-82; ML 0.34-0.48; MI 39-52; WL 1.05-1.30; PrW 0.52-0.69; PL 0.19-0.26; PPL 0.22-0.27; GL 0.70-0.92; FL 0.92-1.14; TL 3.30-4.05.

Color yellow to brownish, opaque, clypeus castaneous; masticatory border, median portion of clypeus, labrum, frontal area and coronal suture dark brown. Area between preocular and frontal carinae hairless. Surface of frons with small irregular pores; a single seta coming out from each of them (only visible with higher magnifications). Whole body, legs and antennae with short, sparse and appressed white hairs, brighter than integument, but the area between preocular carinae and frontal carinae, lateral faces of the mesosoma, dorsal discs of the coxae and petiole with even sparser pilosity. Masticatory border of mandibles with longer hairs. Sculpture reticulate. Mandibular dorsal disc with very fine longitudinal rugae. Integument of the frontal lobes with a rounded semitransparent spot on each side, above the antennal insertions, darker than the rest of the integument of the frontal lobes.

Head as long as wide (see CI), almost heart-shaped. Margin of vertexal in full face view concave, poserolateral corners rounded. Compound eyes with eleven ommatidia at maximum length and nine ommatidia at maximum width. Masticatory border of mandibles with seven to eight triangular teeth, the three most apical the same in size, the others somewhat smaller. Anterior margin of clypeus almost straight. Frontal lobes slender, covering the antennal insertions, but their maximum expansions attaining less than half the distance between the median line and external border of the head. External margin of frontal lobes gently rounded. Frontal and lateral carinae continuing posteriorly up to half the distance between the posterior margin of the eyes and vertexal margin. Antennal scapes slightly curved apically, only reaching the posterolateral corners of the head. Antennae ending in a two segmented club, the last antennal segment as long as the two before combined.

Pronotum convex with vestigial tumuli and pointed inferior pronotal spines. In lateral view mesonotum separated from pronotum by a distinct rounded suture, mesonotum projecting over the pronotum. Metapropodeal impression shallow. Basal face of propodeum slightly convex, a little longer than the straight declivous face meeting in an angle, but lacking spines or protuberances. Inferior margin of pronotum, katepisternum and metapleura bordered by a broad translucent carina. Propodeal spiracle small, with rounded opening 45° oblique in relation to the main body axis. Node of petiole as wide as high, in dorsal view, twice as wide as peduncle; ventral process as an acute denticle. Postpetiole wider than high.

Queen

Range of measurements (in mm) and indices of examined specimens (N = 10): IOD 1.14-1.20; HL 1.00-1.12; CI 104-116; SL 0.82-0.9; SI 71-78; ML 0.48-0.56; MI 44-52; WL 1.64-1.68; PL 0.30-0.36; PPL 0.24-0.32; GL 1.32-1.40; TL 5.10-5.30.

Color yellow to brownish, depending on age, masticatory border of mandibles, middle portion of clypeus, frontal area, area in front and lateral to the ocelli, and parapsidial areas brownish. Most characters as in the conspecific workers. Compound eyes with 18 ommatidia at maximum length and 14 ommatidia at maximum width. Pronotum with blunt anterior inferior spines. In lateral view, flattened scutum covering almost two thirds of pronotum. Notaulices indistinct. Parapsidial lines shallowly impressed. Scutellum subquadrate, anterior margin slightly concave, wider anteriorly; posterior margin concave with vestigial spines. Anepisternum subtriangular and katepisternum subquadrate, separated from the metapleura by a distinct suture.

Male

Range of measurements (in mm) and indices of examined specimens (N = 9): IOD 0.56-0.68; HL 0.56-0.68; CI 97-103; SL 0.58-0.76; SI 100-112; ML 0.24-0.30; MI 40-45; WL 1.30-1.70; PL 0.20-0.30; PPL 0.18-0.24; GL 0.94-1.34; TL 3.50-4.56.

Color dark brown, mandibles, antennae and legs yellowish. Integument reticulate with golden appressed shiny hairs. Hairs at external margin of mandible twice the length of the others. Mandibles with six to seven triangular teeth, decreasing in size from apical to basal, sometimes with varying distances between them. Clypeus anterior margin straight, with a distinct median impression on the anteclypeus. Median seta visible, with size similar to the mandible hairs. Median portion of clypeus bulging up to the level of half of the antennal insertions. Frontal carinae visible until the level of the posterior margin of compound eyes. Lateral carinae following the compound eyes, straight and directed backwards at posterior third. Compound eyes with 18 ommatidia at maximum length and 14 ommatidia at maximum width. Antennae 13-segmented. Antennal scapes straight, surpassing posterolateral corners of the head by half of their length. Antennal apical segment as long as the two preceding segments.

In dorsal view, anterior margin of scutum rounded, posterior margin convex. Parapsidial lines distinctly impressed, shiny, glabrous. Lateral margins of scutum as strong carinae. Prescutellum relatively wide, axillae subtriangular. Scutum-scutellar sulcus with transverse rugae. In lateral view anepisternum subtriangular and katepisternum subquadrate. Median coxa occupying only the posterior fourth of katepisternum inferior margin. Propodeal spiracle parallel in relation to the main body axis.

Petiolar peduncle reduced and node strongly developed, rounded. Ventral process poorly developed. Anterior margin of node meeting the peduncle in a square angle, dorso-posterior portion concave, in side view. In dorsal view, petiole subrectangular and slightly wider anteriorly. Postpetiole in dorsal view subquadrate, wider than petiole, wider posteriorly. Spiracle of first gastral tergite visible.

Karyotype

• n = 18, 2n = 36, karyotype = 20M+16SM (Brazil) (Cardoso et al., 2012a; Cardoso et al., 2014).
• 2n = 36, karyotype = 10M + 8SM (Brazil) (Micolino et al., 2019).

References

• Albuquerque, E.Z.de, Diehl-Fleig, E., Diehl, E. 2005. Density and distribution of nests of Mycetophylax simplex (Emery) (Hymenoptera, Formicidae) in areas with mobile dunes on the northern coast of Rio Grande do Sul, Brazil. Revista Brasileira de Entomologia 49(1): 123-126.
• Cardoso DC, das Grac¸as Pompolo S, Cristiano MP, Tavares MG (2014) The Role of Fusion in Ant Chromosome Evolution: Insights from Cytogenetic Analysis Using a Molecular Phylogenetic Approach in the Genus Mycetophylax. PLoS ONE 9(1): e87473 (doi 10.1371/journal.pone.0087473).
• Cardoso, D. C., Cristiano, M. P. 2021. Karyotype diversity, mode, and tempo of the chromosomal evolution of Attina (Formicidae: Myrmicinae: Attini): Is there an upper limit to chromosome number? Insects 1212, 1084 (doi:10.3390/insects12121084).
• Cardoso, D., Cristiano, M., Tavares, M., Schubart, C., & Heinze, J. (2015). Phylogeography of the sand dune ant Mycetophylax simplex along the Brazilian Atlantic Forest coast: remarkably low mtDNA diversity and shallow population structure. BMC Evolutionary Biology, 15, 106 (doi:10.1186/s12862-015-0383-4).
• Cardoso, D.C., Cristiano, M.P., Tavares, M.G. & Schoereder, J.H. 2012. Co-occurrence of putatively allopatric species of the genus Mycetophylax: first record of Mycetophylax simplex (EMERY, 1888) (Hymenoptera: Formicidae) from Rio de Janeiro State, Brazil. Myrmecological News 16:57-59.
• Cardoso, D.C., Heinze, J., Moura, M.N., Cristiano, M.P. 2018. Chromosomal variation among populations of a fungus-farming ant: implications for karyotype evolution and potential restriction to gene flow. BMC Evolutionary Biology 18, 146 (doi:10.1186/s12862-018-1247-5).
• Cardoso, D.C., Schoereder, J.H. 2014. Biotic and abiotic factors shaping ant (Hymenoptera: Formicidae) assemblages in Brazilian coastal sand dunes: The case of restinga in Santa Catarina. Florida Entomologist 97, 1443–1450. (doi:10.1653/024.097.0419).
• Emery, C. 1888c [1887]. Formiche della provincia di Rio Grande do Sûl nel Brasile, raccolte dal dott. Hermann von Ihering. Bull. Soc. Entomol. Ital. 19: 352-366 (page 361, worker described)
• Emery, C. 1913c. Études sur les Myrmicinae. [V-VII.]. Ann. Soc. Entomol. Belg. 57: 250-262 (page 251, Combination in C. (Mycetophylax))
• Hanisch, P.E., Sosa-Calvo, J., Schultz, T.R. 2022. The last piece of the puzzle? Phylogenetic position and natural history of the monotypic fungus-farming ant genus Paramycetophylax (Formicidae: Attini). Insect Systematics and Diversity 6 (1): 11:1-17 (doi:10.1093/isd/ixab029).
• Jesovnik, A., Sosa-Calvo, J., Lloyd, M.W., Branstetter, M.G., Andez. F.F., Schultz, T.R. 2017. Phylogenomic species delimitation and host-symbiont coevolution in the fungus-farming ant genus Sericomyrmex Mayr (Hymenoptera: Formicidae): ultraconserved elements (UCEs) resolve a recent radiation. Systematic Entomology 42, 523–542 (doi:10.1111/syen.12228).
• Kempf, W. W. 1972b. Catálogo abreviado das formigas da regia~o Neotropical. Stud. Entomol. 15: 3-344 (page 146, Combination in Mycetophylax)
• Klingenberg, C. & Brandão, C.R.F. 2009. Revision of the fungus-growing ant genera Mycetophylax Emery and Paramycetophylax Kusnezov rev. stat. and description of Kalathomyrmex n. gen. Zootaxa 2052: 1-31.
• Klingenberg, C., C. R. F. Brandão, and W. Engels. 2007. Primitive nest architecture and small monogynous colonies in basal Attini inhabiting sandy beaches of southern Brazil. Stud. Neotrop. Fauna Environ. 42:121-126. doi:10.1080/01650520601065509
• Larrea, D.D., Mourglia V., Gonzalez-Vainer, P. 2016. Mycetophylax simplex (Emery, 1888) (Hymenoptera: Formicidae): first record in Uruguay and distribution extension. Check List 12(2): 1869 (doi: http://dx.doi.org/10.15560/12.2.1869).
• Micolino, R., Cristiano, M.P., Travenzoli, N.M., Lopes, D.M., Cardoso, D.C. 2019. Chromosomal dynamics in space and time: evolutionary history of Mycetophylax ants across past climatic changes in the Brazilian Atlantic coast. Scientific Reports 9, 18800 (doi:10.1038/s41598-019-55135-5).
• Moura, M.N., Cardoso, D.C., Cristiano, M.P. 2020. The tight genome size of ants: diversity and evolution under ancestral state reconstruction and base composition. Zoological Journal of the Linnean Society, zlaa135 (doi:10.1093/zoolinnean/zlaa135).
• Santschi, F. 1922c. Myrmicines, dolichodérines et autres formicides néotropiques. Bull. Soc. Vaudoise Sci. Nat. 54: 345-378 (page 355, worker described)
• Santschi, F. 1923c. Solenopsis et autres fourmis néotropicales. Rev. Suisse Zool. 30: 245-273 (page 268, Replacement name: pauper)
• Sosa-Calvo, J., JesÏovnik, A., Vasconcelos, H.L., Bacci, M. Jr., Schultz, T.R. 2017. Rediscovery of the enigmatic fungus-farming ant "Mycetosoritis" asper Mayr (Hymenoptera: Formicidae): Implications for taxonomy, phylogeny, and the evolution of agriculture in ants. PLoS ONE 12: e0176498 (DOI 10.1371/journal.pone.0176498).

References based on Global Ant Biodiversity Informatics

• 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.