Myrmicine
Guides
Aphaenogaster fulva
Tawny Collared Ant
Aphaenogaster fulva is a species of myrmicine ant in the genus Aphaenogaster, first described by Roger in 1863. It is part of a species complex that has undergone taxonomic revision, with some authorities treating related forms as separate species or subspecies. The species has been studied for its spatial distribution patterns in temperate forests, particularly in relation to environmental gradients such as soil moisture and vegetation cover. Like other Aphaenogaster species, it is a ground-nesting ant with generalist foraging habits.
Aphaenogaster uinta
Aphaenogaster uinta is a myrmicine ant species described by Wheeler in 1917. It is native to the western United States and may also occur in Saskatchewan, Canada. Like other members of the genus Aphaenogaster, it belongs to the spine-waisted ant group, though specific details about its biology and ecology remain poorly documented in the available literature.
Cyphomyrmex rimosus
Rimose Fungus-farming Ant
Cyphomyrmex rimosus is a fungus-growing ant in the tribe Attini, native to the Neotropics. It is a small, slow-moving species that cultivates fungal gardens for food. Colonies are typically small, with fewer than 500 workers. Workers are known to feign death when disturbed, remaining immobile for extended periods.
Eurhopalothrix
Eurhopalothrix is a genus of small myrmicine ants in the tribe Attini. Species are characterized by distinctive shield-like facial structures with reduced eyes and specialized mandibular dentition. The genus occurs primarily in the Neotropics, with documented records from Central America through northern South America and into the Atlantic Forest of Brazil and temperate grasslands of Argentina. Several species have been described in recent taxonomic revisions, including 33 new species from Central America documented by Jack Longino.
Formicoxenus hirticornis
Dogwood Guest Ant
Formicoxenus hirticornis is a small myrmicine ant species in the genus Formicoxenus, commonly known as the Dogwood Guest Ant. Species in this genus are specialized social parasites that inhabit nests of larger host ant species, particularly those in the genus Myrmica. The specific epithet 'hirticornis' refers to hairy antennae. This species is rarely encountered and poorly documented in scientific literature.
Leptothorax acervorum
acorn ant
Leptothorax acervorum is a small myrmicine ant first described by Fabricius in 1793. It exhibits a Holarctic distribution spanning Europe, northern Asia, and North America. The species is notable for its facultatively polygynous social structure, where colonies may contain one or multiple queens. Workers display a distinctive two-toned coloration with darker head and metasoma contrasting with a lighter mesosoma. Body size increases with latitude following Bergmann's rule, with boreal populations producing workers approximately 10% larger than those from central Europe.
Leptothorax canadensis
Northern Thin Ant
Leptothorax canadensis is a small myrmicine ant native to eastern North America, where it is one of the most common ants in boreal coniferous forests. The species exhibits facultative polygyny, with colonies containing multiple fertile queens. It is also known as a slave-making ant, conducting organized raids on host colonies—particularly Leptothorax muscorum—to capture pupae that emerge as workers serving the slave-making colony. Genetic studies indicate a multicolonial population structure with moderate gene flow and no evidence of inbreeding.
Myrmica punctiventris
Myrmica punctiventris is a species of ant in the genus Myrmica, family Formicidae. It has been studied in the context of micronutrient distribution among social insect castes. The species is part of the ecologically significant Myrmica genus, which includes ants known for associations with various invertebrates including butterfly larvae.
Orasema
Orasema is a genus of chalcid wasps in the family Eucharitidae containing at least 50 described species. These wasps are specialized parasitoids of myrmicine ants (Formicidae: Myrmicinae), with documented hosts including Pheidole, Wasmannia, and Solenopsis. The genus is widespread in the New World, ranging from northern Argentina to southern Canada. Several species groups have been established based on morphology and molecular phylogeny, with the stramineipes group being the most diverse. Some species have been associated with minor agricultural damage when ovipositing into crop plant leaves.
Pheidole cerebrosior
Pheidole cerebrosior is a species of higher myrmicine ant in the family Formicidae, described by Wheeler in 1915. It belongs to the hyperdiverse genus Pheidole, which is characterized by worker polymorphism with distinct major and minor castes. The species is part of the Attini tribe, which includes the well-known fungus-growing ants, though Pheidole species are not fungus-growers themselves. Information regarding its biology, ecology, and distribution remains limited in the available literature.
Pheidole crassicornis
crassicornis-group Big-headed Ants
Pheidole crassicornis is a species of big-headed ant in the genus Pheidole, family Formicidae, first described by Emery in 1895. The species belongs to the crassicornis complex within this diverse ant genus. Two subspecies are recognized: P. c. crassicornis (the nominate form) and P. c. tetra (described by Creighton in 1950). Like other Pheidole species, it exhibits the characteristic worker polymorphism with distinct major and minor worker castes.
Pheidole dentigula
Woodland Big-headed Ant
Pheidole dentigula is a species of big-headed ant in the genus Pheidole, first described by Smith in 1927. As with other members of this hyperdiverse genus, it exhibits a dimorphic worker caste system with minor workers and major soldiers. The species is native to North America and has been documented in woodland habitats.
Pheidole metallescens
Metallic Big-headed Ant
Pheidole metallescens is a species of big-headed ant in the genus Pheidole, first described by Emery in 1895. The species exhibits the characteristic dimorphic worker caste system typical of the genus, with minor workers and major workers (soldiers) possessing disproportionately large heads. Two subspecies are recognized: P. m. metallescens and P. m. splendidula. The species belongs to the diverse myrmicine ant tribe Attini.
Pheidole morrisii
Morris' Big-headed Ant
Pheidole morrisii is a species of big-headed ant in the genus Pheidole, first described by Forel in 1886. Like other members of this hyperdiverse genus, it exhibits the characteristic dimorphic worker caste system with minor workers and major workers (soldiers) bearing disproportionately enlarged heads. The species belongs to the myrmicine subfamily and is part of the tribe Attini.
Pheidole obtusospinosa
Blunt-spined Big-headed Ant
Pheidole obtusospinosa is a species of big-headed ant in the genus Pheidole, characterized by soldier ants with enlarged, squared heads used for nest defense. The species belongs to the hyperdiverse ant genus Pheidole, which contains over 1,000 species globally. Soldiers of this species have been observed using their modified heads to block nest entrances against intruders, particularly army ants such as Eciton burchelli. The species was described by Pergande in 1896.
Pheidole tysoni
Tyson's Big-headed Ant
Pheidole tysoni is a species of big-headed ant in the genus Pheidole, described by Auguste Forel in 1901. As a member of this hyperdiverse ant genus, it exhibits the characteristic worker polymorphism with distinct major and minor worker castes. The species is part of the myrmicine subfamily and is classified within the Attini tribe. Available information about its biology and ecology remains limited in the provided sources.
Protomognathus
Protomognathus is a genus of myrmicine ants containing obligatory slave-making species. The genus includes Protomognathus americanus, which exhibits a "prudent" slave-making strategy characterized by minimal fitness impact on host colonies compared to more destructive slave-makers. Scout workers actively seek host colonies, and colony size influences both scouting behavior and host defensive responses.
Solenopsis tonsa
Thompson's Thief Ant
Solenopsis tonsa is a species of thief ant described by Thompson in 1989. It belongs to the genus Solenopsis, which includes the well-known red imported fire ant (Solenopsis invicta). The species is commonly referred to as Thompson's Thief Ant. Very few observations of this species have been recorded, with only four documented observations on iNaturalist as of the knowledge cutoff. As a member of the Solenopsis genus, it shares the general morphological characteristics of small myrmicine ants, though specific distinguishing features from congeners are not well documented in available sources.
Temnothorax caguatan
Temnothorax caguatan is a species of small myrmicine ant described in 2014 from California, USA. It belongs to a genus of cavity-nesting ants known for nesting in pre-existing cavities such as hollow acorns, twigs, and rock crevices. The species was one of ten new Temnothorax species described from California in a single study, effectively doubling the known species diversity of this genus in the state. Like other members of Temnothorax, it is likely a generalist scavenger with colonies of moderate size.
Temnothorax nevadensis
Nevada Acorn Ant
Temnothorax nevadensis is a species of acorn ant in the family Formicidae, originally described by Wheeler in 1903. Like other members of the genus, it is a small ant species that typically nests in preformed cavities such as hollow nuts or acorns. The species is part of a diverse genus containing over 350 species worldwide, with approximately 60 species known from North America.
Trachymyrmex nogalensis
Trachymyrmex nogalensis is a fungus-gardening ant species from southern Arizona, described by Byars in 1951. As a member of the attine tribe, it cultivates fungal gardens as its primary food source. The queen caste was first characterized in a 2007 taxonomic revision, having previously been undescribed. The species is one of nine North American Trachymyrmex species recognized in that revision.