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Temporal range: 20.43–0 Ma Miocene – Recent
Cephalotes atratus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Cephalotes
Latreille, 1802
Type species
Formica atrata, now Cephalotes atratus
123 species
16 fossil species
(Species Checklist, Species by Country)

Cephalotes atratus casent0173663 profile 1.jpg

Cephalotes atratus

Cephalotes atratus casent0178627 dorsal 1.jpg

Specimen Label

Evolutionary Relationships

Ochetomyrmex (2 species), Tranopelta (2 species)

Allomerus (8 species), Blepharidatta (4 species), Diaphoromyrma (1 species), Lachnomyrmex (16 species), Wasmannia (11 species)

Acanthognathus (7 species), Colobostruma (16 species), Daceton (2 species), Epopostruma (20 species), Lenomyrmex (7 species), Mesostruma (9 species), Microdaceton (4 species), Orectognathus (29 species),

Acromyrmex (55 species), Apterostigma (44 species), Atta (20 species), Cyatta (1 species), Cyphomyrmex (23 species), Kalathomyrmex (1 species), Mycetophylax (21 species), Mycetagroicus (4 species), Mycetarotes (4 species), Mycetosoritis (2 species), Mycocepurus (6 species), Myrmicocrypta (31 species), Sericomyrmex (11 species), Trachymyrmex (9 species), Xerolitor (1 species)

  (1,294 species)

  (123 species)

  (44 species)

  (853 species)

  (1 species)

  (1 species)

  (7 species)

  (16 species)

  (8 species)

  (34 species)

  (53 species)

  (1 species)

Based on Ward et al. (2014), Blaimer et al. (2018) and Li et al. (2018).

Common in the New World tropics, Turtle ants have long attracted the attention of tropical biologists due to their unusual soldier caste with large armored heads that match the size and shape of their nest entrances. Nests occupy pre-existing arboreal cavities, and soldiers function as living doors to admit incoming foragers or exclude potential intruders.

Cephalotes (119 species) consume a mostly herbivorous diet supplemented by pollen, bird feces and vertebrate urine (e.g. Cephalotes atratus) (Baroni Urbani and de Andrade 1997; Powell 2008).

Photo Gallery

  • Cephalotes atratus dealate queen from Surinam. Copyright: Piotr Naskrecki
  • A worker from Dominican amber.
  • A young spider, Aphantochilus roguersi, of the family Thomisidae (crab spiders), a predator (and mimic) of Cephalotes, photographed in Manaus, Brazil, by Thiago Gomes de Carvalho.
  • Aphantochilus rogersi is a species of ant-mimicking crab spiders from South America. It is found from Panama to Paraguay. It mimics ants of the genus Cephalotes, which are their preferred prey. It has the unusual behaviour of carrying the dead husks of ants aloft like a protective umbrella. This may camouflage or hide its identity and allow it to approach and overpower other ants, or it may be a form of defence to protect itself from its enemies. Photo by Gil Wizen.


De Andrade and Baroni Urbani (1999) assigned Cephalotes species to clades.

AntWeb icon 02.png See images of species within this genus

Keys including this Genus


Keys to Species in this Genus


Distribution and Richness based on AntMaps


Fossils are known from: Dominican amber, Dominican Republic (Burdigalian, Early Miocene), Mexican amber, Chiapas, Mexico (Middle Miocene).


The biology of many Cephalotes species is not known. Ants in this genus are common in the New World tropics and subtropics and are especially abundant and diverse in the canopies of Neotropical forests. The majority of species are arboreal. Species that live in other strata inhabit smaller trees, bushes or grass stems. These noon-arboreal species, due to their accessibility, are among the better studied members of the genus. There are also species that can be found in downed wood but it is likely the wood housed the colony before it fell to the ground. Soil nests are not known for any species nor do most species appear to extensively excavate plant tissue. They nest instead in preformed cavities. Overall, ants in the genus utilize a wide range of plants. Some species are predictable in their plant use but none appear to have evolved specialized mutualisms with particular plant species.

Worker castes typically include two forms, a worker and soldier, but there are a few species that are monomorphic. The larger soldier caste typically has an enlarged head disk. In some species the head of the soldier is very different from the worker while in others these differences are less pronounced. Queens and soldiers tend to share similar head morphology. Soldiers use their heads to plug the nest entrance. This can be very effective in excluding potential intruders. Other morphological differences between the worker castes are present but these differences have not been studied as well as head moprhology.

The behavioral repertoire of Cephalotes varians has been examined in great detail (ethograms from Wilson 1976, Cole 1980 and Cole 1983). Soldiers do little else besides defend the nest. This specialized soldier behavior is presumed to be the norm for most species. An especially interesting behavior occurs when workers are dislodged from trees: they "fly" towards the tree, often grabbing the trunk well above the ground (video).

Mature nest size varies, by species, from less than a hundred to many thousands of workers. Available evidence suggests most species are monogynous. Queens may mate with multiple males.

The proventriculus of the Cephalotes is peculiar relative to other ants. The morphology of the structure suggests it serves as a powerful pump and filter. This does not appear to lead these ants to have a highly specialized diet as most species appear to be general scavengers. Foragers have been observed feeding on carrion, bird feces, extrafloral nectaries and even tending membracids. Pollen feeding has been observed in some species, and this is somewhat specialized for ants, but it is not evident that any species restricts its diet to this resource in any significant way. Evidence for pollen feeding in Cephalotes has accumulated, in part, via finding digested pollen grains seen in infrabucal pellets. It has been suggested that the morphology of the proventriculus is a specialization for processing pollen.

More research examining all aspects of the biology of Cephalotes is needed. Our present understanding of these ants is largely based on species that live in locations other than the forest canopy, which is where Cephalotes are most common and diverse.

Association with Other Organisms

All Associate Records for Genus

Explore Associate Data: All, Drilldown
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Taxon Relationship Associate Type Associate Taxon Associate Relationship Locality Source Notes
Cephalotes atratus host fungus Ophiocordyceps cucumispora pathogen Araujo et al., 2018; Shrestha et al., 2017
Cephalotes atratus host fungus Ophiocordyceps evansii pathogen Sanjuan et al., 2015; Araujo et al., 2018; Shrestha et al., 2017
Cephalotes atratus host fungus Ophiocordyceps kniphofioides pathogen Shrestha et al., 2017
Cephalotes atratus host fungus Ophiocordyceps niphofioides pathogen Araujo et al., 2018; Shrestha et al., 2017
Cephalotes atratus host nematode Myrmeconema neotropicum parasite Peru, Panama Poinar & Yanoviak, 2008
Cephalotes atratus host phorid fly Apocephalus catholicus parasite Brown et al., 2015 injured
Cephalotes atratus host phorid fly Apocephalus roeschardae parasite Brown et al., 2015 injured
Cephalotes atratus host phorid fly Apocephalus roeschardae parasite phorid.net attacked
Cephalotes atratus host phorid fly Diocophora sp parasite Brown et al., 2015 injured
Cephalotes atratus host phorid fly Megaselia sp parasite Brown et al., 2015 injured
Cephalotes minutus host nematode Agamomermis cephaloti parasite Brazil Poinar et al., 2006
Cephalotes serratus host nematode Palaeoallantonema cephalotae parasite Dominican amber Poinar, 2011 Dominican amber
Cephalotes specularis xenobiont ant Crematogaster ampla host Powell et al., 2014

Life History Traits

  • Mean colony size: ~10000 (Greer et al., 2021)
  • Compound colony type: not parasitic (Greer et al., 2021)
  • Nest site: arboreal (Greer et al., 2021)
  • Diet class: herbivore (Greer et al., 2021)
  • Foraging stratum: arboreal (Greer et al., 2021)
  • Foraging behaviour: cooperative (Greer et al., 2021)


Powell (2016) studied how nesting ecology in Cephalotes has shaped the diversification of an elaborate soldier caste. The evolution of morphologically specialized soldier heads was associated with substantial shifts in nest-entrance preferences, and in many species there is a match between head sizes and entrance sizes. These findings suggest the general hypothesis that the evolution of novel caste types is driven by major shifts in ecological specialization, while the size distribution of existing castes tracks minor shifts in resource use.


Worker Morphology

 • Eyes: >100 ommatidia • Pronotal Spines: dentiform; present • Mesonotal Spines: absent • Propodeal Spines: absent; present • Petiolar Spines: absent • Caste: polymorphic • Sting: absent • Metaplural Gland: present • Cocoon: absent


All Karyotype Records for Genus

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Taxon Haploid Diploid Karyotype Locality Source Notes
Cephalotes pusillus 22 44 28M+16A Brazil Cristiano et al., 2017


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

  • CEPHALOTES [Myrmicinae: Cephalotini]
    • Cephalotes Latreille, 1802a: 357. Type-species: Formica atrata, by monotypy.
    • [Type-species not Formica cephalotes, unjustified subsequent designation by Wheeler, W.M. 1911f: 160; corrected by Wheeler, W.M. 1913a: 78.]
    • Cephalotes junior synonym of Cryptocerus: Fabricius, 1804: 419.
    • Cephalotes senior synonym of Cryptocerus: Wheeler, W.M. 1913a: 78; Smith, M.R. 1949c: 19; Kempf, 1951: 107.
    • Cephalotes senior synonym of Eucryptocerus, †Exocryptocerus, Zacryptocerus (and its junior synonyms Cyathocephalus, Cyathomyrmex, Harnedia, Hypocryptocerus, Paracryptocerus): De Andrade & Baroni Urbani, 1999: 59.
  • CRYPTOCERUS [junior synonym of Cephalotes]
    • Cryptocerus Latreille, 1803: 311. Type-species: Formica atrata, by subsequent designation of Latreille, 1810: 437.
    • [Type-species not Cryptocerus umbraculatus, unjustified subsequent designation by Emery, 1914c: 38; repeated in Emery, 1924d: 305.]
    • Cryptocerus junior synonym of Cephalotes: Wheeler, W.M. 1913a: 78; Smith, M.R. 1949c: 19; see also discussion in Kempf, 1951: 105. [Cephalotes and Cryptocerus share the same type-species, synonymy is therefore absolute.]
  • CYATHOMYRMEX [junior synonym of Cephalotes]
    • Cyathomyrmex Creighton, 1933: 100 [as subgenus of Cryptocerus]. Replacement name for Cyathocephalus Emery, above. [Junior homonym of Cyathocephalus Kessler, 1868: 135 (Cestoda).]
    • Cyathomyrmex subgenus of Paracryptocerus: Smith, M.R. 1949c: 21.
    • Cyathomyrmex junior synonym of Paracryptocerus: Kempf, 1972a: 175.
    • Cyathomyrmex junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.
  • EUCRYPTOCERUS [junior synonym of Cephalotes]
    • Eucryptocerus Kempf, 1951: 127. Type-species: Cryptocerus oculatus, by original designation.
    • Eucryptocerus junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.
  • EXOCRYPTOCERUS [junior synonym of Cephalotes]
    • Exocryptocerus Vierbergen & Scheven, 1995: 159. Type-species: †Exocryptocerus serratus, by original designation.
    • Exocryptocerus junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.
  • HARNEDIA [junior synonym of Cephalotes]
    • Harnedia Smith, M.R. 1949c: 20 [as subgenus of Paracryptocerus]. Type-species: Cryptocerus umbraculatus, by original designation.
    • Harnedia junior synonym of Paracryptocerus: Kempf, 1972a: 175.
    • Harnedia junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.
  • HYPOCRYPTOCERUS [junior synonym of Cephalotes]
    • Hypocryptocerus Wheeler, W.M. 1920: 53 [as subgenus of Cryptocerus]. Type-species: Formica haemorrhoidalis, by original designation.
    • Hypocryptocerus raised to genus: Wheeler, W.M. 1936b: 200.
    • Hypocryptocerus junior synonym of Zacryptocerus: Kempf, 1973c: 460.
    • Hypocryptocerus junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.
  • PARACRYPTOCERUS [junior synonym of Cephalotes]
    • Paracryptocerus Emery, 1915i: 192 [as subgenus of Cryptocerus]. Type-species: Cryptocerus spinosus, by original designation.
    • Paracryptocerus raised to genus: Smith, M.R. 1949c: 20; Kempf, 1951: 153.
    • Paracryptocerus senior synonym of Cyathocephalus (homonym), Cyathomyrmex, Harnedia: Kempf, 1972a: 175.
    • Paracryptocerus junior synonym of Zacryptocerus: Kempf, 1973c: 460.
    • Paracryptocerus junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.
  • ZACRYPTOCERUS [junior synonym of Cephalotes]
    • Zacryptocerus Wheeler, W.M. 1911f: 175 (see also footnote). Type-species: Cryptocerus clypeatus, by original designation.
    • [Zacryptocerus Ashmead, 1905b: 384. Nomen nudum. (Based on a non-existent type-species: Cryptocerus multistrigus. Nomen nudum, attributed to Smith, F.).]
    • Zacryptocerus senior synonym of Hypocryptocerus, Paracryptocerus (and its junior synonyms Cyathomyrmex, Cyathocephalus (homonym), Harnedia): Kempf, 1973c: 460.
    • Zacryptocerus junior synonym of Cephalotes: De Andrade & Baroni Urbani, 1999: 59.