AntWiki: The Ants --- Online
Jump to navigation Jump to search
Phalacromyrmex fugax
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Phalacromyrmex
Kempf, 1960
Type species
Phalacromyrmex fugax
1 species
(Species Checklist, Species by Country)

Phalacromyrmex fugax casent0103116 profile 1.jpg

Phalacromyrmex fugax

Phalacromyrmex fugax casent0103116 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 (56 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)

  (859 species)

  (1 species)

  (1 species)

  (7 species)

  (16 species)

  (9 species)

  (35 species)

  (55 species)

  (1 species)

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

The only species in the genus, Phalacromyrmex fugax, has been collected in forest habitats. The genus is endemic to Brazil and little is known about the biology of these ants.


Although quite distinct in its own right, this new genus seems at least superficially related with the ants of the tribe Dacetini in the subfamily Myrmicinae. As regards the number of antennal segments, it agrees with the Daceton-complex, but is otherwise completely different in head shape, short triangular mandibles, position of eyes and development of antennal scrobe. By its general habitus Phalacrornyrmex seemingly imitates the short-mandibulate members of the strumigenys-complex, especially Codiomyrmex and Glamyromyrmex (=Strumigenys). However, many important characters, such as the number of antennal segments, the unarmed petiolar and postpetiolar nodes, lacking any trace of spongiform appendages, the normally ovate gaster, lacking an anterior truncation and transverse crest, separate it also from this group. The peculiar palpal formula - maxillary palps with 3, labial palps with 2 segments - removes Phalacrornyrmex from all known Dacetine genera. As long as the sexual forms and the larvae are unknown, it seems best not to include the present genus in the Dacetini, although it seems even farther removed from all other Myrmecine tribes. (Kempf 1960)

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

Keys including this Genus



Distribution and Richness based on AntMaps

Species by Region

Number of species within biogeographic regions, along with the total number of species for each region.

Afrotropical Region Australasian Region Indo-Australian Region Malagasy Region Nearctic Region Neotropical Region Oriental Region Palaearctic Region
Species 0 0 0 0 0 1 0 0
Total Species 2837 1734 3036 929 832 4375 1686 2823


Life History Traits

  • Mean colony size: ? (Greer et al., 2021)
  • Compound colony type: not parasitic (Greer et al., 2021)
  • Nest site: hypogaeic (Greer et al., 2021)
  • Diet class: ? (Greer et al., 2021)
  • Foraging stratum: ? (Greer et al., 2021)



Worker Morphology

 • Eyes: 11-100 ommatidia • Pronotal Spines: absent • Mesonotal Spines: absent • Propodeal Spines: dentiform • Petiolar Spines: absent • Caste: none or weak • Sting: present • Metaplural Gland: present • Cocoon: absent


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

  • PHALACROMYRMEX [Myrmicinae: Phalacromyrmecini]
    • Phalacromyrmex Kempf, 1960b: 89. Type-species: Phalacromyrmex fugax, by original designation.

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

Worker - Mandibles short, broadly triangular, strongly curved laterad and apicad; chewing border serially dentate, larger teeth alternating with smaller ones. Labrum bilobed. Palpal formula 3:2. Antennae 11-segmented, funiculus with a 2-segmented apical club. Frontal carinae broadly expanded laterad and foreward, covering cheeks and eyes in full-face view. Clypeus flanked by the frontal carinae, its anterior border scarcely convex. Eyes small, situated ventrolaterally below the deeply excavate antennal scrobe. Thorax dorsally flattened, laterally marginate; mesoepinotum conspicuously compressed. Epinotum with a pair of upright triangular lamellae. Middle and hind legs without a tibial spur. Petiole strongly pedunculate. Both petiolar and postpetiolar nodes little broader than long, unarmed, lacking spongiform appendages. Gaster ovate, its anterior end not truncate, lacking a transverse crest. Body integument mostly smooth and shining. Erect hairs simple, short, very scarce, absent on dorsum of head. Appressed pilosity scarce and inconspicuous.

Baroni Urbani & De Andrade (2007) - Only one unequivocal synapomorphy for this genus results from our data, the presence of mesopleural costulation. CI 1.00, RI 0.00. We doubt, however the generic rank of this character. Other apomorphic characters resulting from our analysis are:

Worker (and gyne?) presence of a cuticular process of the mesonotum. CI 0.86, RI 0.75. Cuticular projections of the mesonotum are known also in Epopostruma and Strumigenys.

Worker (and gyne?) metapleaural gland bulla close to the annulus. CI 0.62, RI 0.40. The same character state is encountered in a number of non-related Dacetini genera like Protalaridris, Microdaceton, Epopostruma, a. o.

Worker (and gyne?) antennae 11-jointed. CI 0.20, RI 0.50. A character state shared with several outgroups and with Daceton and Acanthognathus.

The pretended generic apomorphies above are likely to be a by-product of the clustering together of the three "Phalacromyrmecini" genera, a clustering that is based on weak characters. We suspect that all the former Phalacromyrmecini genera might be better understood as atypical Strumigenys species.


phalacros - bald-headed; myrmex - an ant