Xerolitor explicatus

Xerolitor explicatus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Xerolitor
Species:	X. explicatus
Binomial name
Xerolitor explicatus (Kempf, 1968) Specimen labels

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -18.112222° to -22.809943°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

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

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. ‎

Xerolitor explicatus is a member of the higher-attine ants, a clade that includes Sericomyrmex, Trachymyrmex, and the leaf-cutting ant genera Acromyrmex and Atta. The phylogeny further indicates that within the higher attines, X. explicatus is the sole representative of a depauperate evolutionary lineage that descended from a common ancestor, shared with the genus Sericomyrmex, that lived ∼15 Ma (Ješovnik et al., 2017). Our results are consistent with those of earlier studies (Branstetter et al., 2017; Ješovnik et al., 2017). Considering the cryptic biology of X. explicatus, it is possible that additional species of the currently monotypic genus Xerolitor remain to be discovered.

Nomenclature

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

• explicatus. Mycetosoritis explicata Kempf, 1968b: 401, figs. 14-16 (w.) BRAZIL.
  • Sosa-Calvo, Brady & Schultz, 2009: 114 (q.).
  • Status as species: Kempf, 1972a: 146; Bolton, 1995b: 269; Wild, 2007b: 33; Sosa-Calvo, Brady & Schultz, 2009: 114.
  • Combination in Xerolitor: Sosa-Calvo et al., 2018: 557.

Type Material

• Holotype, worker, Anápolis, Goiás, Brazil, Museu de Zoologia da Universidade de Sao Paulo.
• Paratype, workers, Anápolis, Goiás, Brazil, Museu de Zoologia da Universidade de Sao Paulo.

Description

Head: Mandible triangular, masticatory margin with eight teeth, which increase gradually in size towards apex. Clypeal apron present, convex, medially concave. Median clypeal seta long (∼1/5 of mandible length), originating on anterior margin of clypeal apron emargination; lateral portion of clypeus with cluster of four to five clypeal hairs each. Preocular carina raised and extending posterad joining frontal carina at posterior cephalic margin forming complete antennal scrobe. Frontal lobe greatly expanded, covering antennal insertion, and jagged. Leading (anterior) edge of antennal scape denticulate, covered with subdecumbent long hairs that project toward apex; posterior edge of antennal scape lacking denticles and bearing appressed hairs. Mesosoma: Dorsum of pronotum flat and with some very low tubercles that bear some decumbent or subdecumbent hairs. Lateral margins of pronotum with denticulate carina. Lateral pronotal spine triangular, large. Lateral mesonotal tubercles large, triangular and keeled, with broad base. Posterior mesonotal lobes carinate. Dorsum of promesonotum forming shield, carinate on all sides, separated from lateral portions of promesonotum by abrupt right angles, and, posteriorly, overhanging and elevated above propodeum. Anterolateral face of propodeum with carinules ending in small tubercles. Metasoma: Petiolar node approximately as long as broad. Postpetiole wider than long; side bearing several denticles of similar length; posterior margin vestigially emarginated. First gastral tergite ovate, with pair of lateral longitudinal carinae along anterior two-thirds; dorsum with small, pimple-like, piligerous tubercles connected to each other by weak but distinct rugae, forming an areolate surface sculpture. In lateral view, first gastral tergite longer than sternite, dorsally overhanging remaining segments.

References

• 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).
• Kempf, W. W. 1968b. Miscellaneous studies on Neotropical ants. IV. (Hymenoptera, Formicidae). Stud. Entomol. 11: 369-415 (page 401, figs. 14-16 worker described)
• Sosa-Calvo, J., S. G. Brady and T. R. Schultz. 2009. The gyne of the enigmatic fungus-farming ant species Mycetosoritis explicata. Journal of Hymenoptera Research 18(1): 113-120.
• Sosa-Calvo, J., Schultz, T.R., Jesovnik, A., Dahan, R.A., Rabeling, C. 2018. Evolution, systematics, and natural history of a new genus of cryptobiotic fungus-growing ants. Systematic Entomology, 43, 549–567 (doi:10.1111/syen.12289).

References based on Global Ant Biodiversity Informatics

• Wild, A. L. "A catalogue of the ants of Paraguay (Hymenoptera: Formicidae)." Zootaxa 1622 (2007): 1-55.