Pheidole californica

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Pheidole californica
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Pheidole
Species: P. californica
Binomial name
Pheidole californica
Mayr, 1870

Pheidole californica casent0006758 profile 1.jpg

Pheidole californica casent0006758 dorsal 1.jpg

Specimen Label


Colonies have been found nesting variously under objects, in oak galls, or in open sandy soil (Cole 1934b; Mallis 1941). Stefan Cover reports a population in moist spots in a grazed Chihuahuan desert at 1295 m in Hidalgo, extreme southwest New Mexico. The colonies were nesting in soil with a high clay content; the most common other ant species was Temnothorax pergandei. (Wilson 2003)


The Pheidole californica complex comprises three closely related and partly sympatric species of seed harvesting ants restricted to the western Nearctic region. Pheidole clementensis Gregg may be distinguished from both Pheidole californica Mayr and Pheidole creightoni Gregg by the diagonal rather than longitudinal rugulae between the clypeus and the eye in lateral View. The closely related P. californica and P. creightoni are most readily distinguished from one another by the angle of their lateral cephalic setae. Pheidole californica has decumbent setae forming an angle of forty-five degrees or less with the lateral margins of the head in full face view, while the cephalic setae of P. creightoni emerge at an angle of approximately ninety degrees. (Burge, 2005.)

See also the description in the nomenclature section.

Keys including this Species


Pheidole californica is broadly distributed in the western Nearctic region (Burge, 2005); California north to Washington, east to Idaho and New Mexico (Wilson, 2003).

Latitudinal Distribution Pattern

Latitudinal Range: 50.78233333° to 28.93333333°.

Tropical South

Distribution based on Regional Taxon Lists

Nearctic Region: United States (type locality).
Neotropical Region: Mexico.

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.


Association with Other Organisms

Explore-icon.png Explore: Show all Associate data or Search these data. See also a list of all data tables or learn how data is managed.
  • This species is a host for the eucharitid wasp Orasema sp. b2 nr bakeri (a parasitoid) (Quevillon, 2018) (encounter mode independent; direct transmission; transmission outside nest).

Flight Period

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec





Images from AntWeb

Pheidole californica casent0005752 head 1.jpgPheidole californica casent0005752 profile 1.jpgPheidole californica casent0005752 dorsal 1.jpgPheidole californica casent0005752 label 1.jpg
Worker. Specimen code casent0005752. Photographer April Nobile, uploaded by California Academy of Sciences. Owned by UCDC, Davis, CA, USA.


Images from AntWeb

Pheidole californica casent0006750 head 1.jpgPheidole californica casent0006750 profile 1.jpgPheidole californica casent0006750 dorsal 1.jpgPheidole californica casent0006750 label 1.jpg
Worker (major/soldier). Specimen code casent0006750. Photographer April Nobile, uploaded by California Academy of Sciences. Owned by CAS, San Francisco, CA, USA.
Pheidole californica casent0005751 head 1.jpgPheidole californica casent0005751 profile 1.jpgPheidole californica casent0005751 dorsal 1.jpgPheidole californica casent0005751 label 1.jpg
Worker (major/soldier). Specimen code casent0005751. Photographer April Nobile, uploaded by California Academy of Sciences. Owned by UCDC, Davis, CA, USA.


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

  • californica. Pheidole californica Mayr, 1870b: 987 (s.w.) U.S.A. Wheeler, W.M. 1915b: 406 (q.); Wheeler, G.C. & Wheeler, J. 1972b: 243 (l.). Senior synonym of incenata, satura: Creighton, 1950a: 173; of pyramidensis: Wheeler, G.C. & Wheeler, J. 1986g: 13; of oregonica (and its junior synonyms hagermani, shoshoni): Wilson, 2003: 564.
  • hagermani. Pheidole californica var. hagermani Cole, 1936a: 35 (s.w.) U.S.A. Junior synonym of oregonica: Creighton, 1950a: 173.
  • incenata. Pheidole californica var. incenata Wheeler, W.M. 1915b: 407 (s.w.) U.S.A. Junior synonym of californica: Creighton, 1950a: 173.
  • nevadensis. Pheidole californica subsp. nevadensis Wheeler, W.M. 1915b: 408 (s.w.q.) U.S.A. [Junior primary homonym of nevadensis Forel, above.] Replacement name: pyramidensis Emery, 1922e: 105.
  • oregonica. Pheidole oregonica Emery, 1895c: 291 (s.w.) U.S.A. Wheeler, W.M. 1915b: 408 (q.). Subspecies of californica: Wheeler, W.M. 1915b: 407; Creighton, 1950a: 173. Senior synonym of hagermani: Creighton, 1950a: 173; of shoshoni: Gregg, 1959: 19. Junior synonym of californica: Wilson, 2003: 564.
  • pyramidensis. Pheidole californica subsp. pyramidensis Emery, 1922e: 105. Replacement name for nevadensis Wheeler, W.M. 1915b: 408. [Junior primary homonym of nevadensis Forel, 1901e: 353.] Junior synonym of californica: Wheeler, G.C. & Wheeler, J. 1986g: 13.
  • satura. Pheidole californica var. satura Wheeler, W.M. 1915b: 407 (s.w.) U.S.A. Junior synonym of californica: Creighton, 1950a: 173.
  • shoshoni. Pheidole californica var. shoshoni Cole, 1933: 618 (s.w.) U.S.A. Subspecies of californica: Creighton, 1950a: 174. Junior synonym of oregonica: Gregg, 1959: 19.

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


From Wilson (2003): A member of the “pilifera subgroup” of the larger pilifera group, comprising Pheidole calens, Pheidole californica, Pheidole carrolli, Pheidole cavigenis, Pheidole clementensis, Pheidole creightoni, Pheidole hoplitica, Pheidole littoralis, Pheidole micula, Pheidole pilifera, Pheidole polymorpha, Pheidole rugulosa, Pheidole senex, Pheidole soritis, Pheidole tepicana and Pheidole torosa, which subgroup is distinguished by the following traits. Major: dorsal head surface extensively sculptured; occipital lobes horizontally rugulose (or, in littoralis, foveate, in carrolli, smooth, and in micula and soritis, carinulate); postpetiole from above diamond-shaped, trapezoidal, or spinose. Minor: eye medium-sized to large.

P. californica is distinguished by the following combination of traits. Color yellow.

Major: all of pronotum smooth and shiny; humerus in dorsal oblique view low and smoothly convex; propodeal spine in side view equilaterally triangular; postpetiole from above trapezoidal. Closest to clementensis, from which it differs by its smaller size (HW in californica major about 0.90 mm, in clementensis major about 1.10 mm) and proportionately larger eye (major EL/HW 0.20 in californica versus 0.13 in clementensis). Also, the sides of the major head are smooth and shiny in some, but not all, californica populations (Philip S. Ward, personal communication).

MEASUREMENTS (mm) Major (Palo Alto, California): HW 0.92, HL 1.06, SL 0.54, EL 0.18, PW 0.44. Minor (Palo Alto): HW 0.48, HL 0.56, SL 0.48, EL 0.12, PW 0.28.

COLOR Major: concolorous yellow; gaster a slightly contrasting brownish yellow.

Minor: yellow with a slight brownish tinge.

Pheidole californica Wilson 2003.jpg

Figure. Upper: major. Lower: minor. CALIFORNICA: Palo Alto. Scale bars = 1 mm.

Type Material

San Francisco. Naturhistorisches Museum Wien, Vienna - as reported in Wilson (2003)


Based on the state of origin of the type series. (Wilson 2003)


References based on Global Ant Biodiversity Informatics

  • Allred D. M. 1982. Ants of Utah. The Great Basin Naturalist 42: 415-511.
  • Allred, D.M. 1982. The ants of Utah. Great Basin Naturalist 42:415-511.
  • Boulton A. M., Davies K. F. and Ward P. S. 2005. Species richness, abundance, and composition of ground-dwelling ants in northern California grasslands: role of plants, soil, and grazing. Environmental Entomology 34: 96-104
  • Burge D. O. 2005. Taxonomy, biology, and distribution of seed harvesting ants in the Pheidole californica complex (Hymenoptera: Formicidae). Journal of Hymenoptera Research 14: 137-150
  • Clarke K.M., Fisher B.L. and LeBuhn G. 2008. The influece of urban park characteristics on ant (Hymenoptera, Formicidae) communities. Urban Ecosyst 11: 317-334
  • Cole A. C., Jr. 1933. Descriptions of two new ants of the genus Pheidole (Hymenoptera: Formicidae). Annals of the Entomological Society of America 26: 616-618.
  • Cole A. C., Jr. 1936. An annotated list of the ants of Idaho (Hymenoptera: Formicidae). Canadian Entomologist 68: 34-39.
  • Cole A. C., Jr. 1942. The ants of Utah. American Midland Naturalist 28: 358-388.
  • Cole, A.C. 1936. An annotated list of the ants of Idaho (Hymenoptera; Formicidae). Canadian Entomologist 68(2):34-39
  • Cover S. P., and R. A. Johnson. 20011. Checklist of Arizona Ants. Downloaded on January 7th at
  • Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology
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  • Fisher B. L. 1997. A comparison of ant assemblages (Hymenoptera, Formicidae) on serpentine and non-serpentine soils in northern California. Insectes Sociaux 44: 23-33
  • Hoey-Chamberlain R. V., L. D. Hansen, J. H. Klotz and C. McNeeley. 2010. A survey of the ants of Washington and Surrounding areas in Idaho and Oregon focusing on disturbed sites (Hymenoptera: Formicidae). Sociobiology. 56: 195-207
  • Holway D.A. 1998. Effect of Argentine ant invasions on ground-dwelling arthropods in northern California riparian woodlands. Oecologia. 116: 252-258
  • Johnson, R.A. and P.S. Ward. 2002. Biogeography and endemism of ants (Hymenoptera: Formicidae) in Baja California, Mexico: a first overview. Journal of Biogeography 29:1009–1026/
  • La Rivers I. 1968. A first listing of the ants of Nevada. Biological Society of Nevada, Occasional Papers 17: 1-12.
  • Mallis A. 1941. A list of the ants of California with notes on their habits and distribution. Bulletin of the Southern California Academy of Sciences 40: 61-100. 
  • Ratchford, J.S., S.E. Wittman, E.S. Jules, A.M. Ellison, N.J. Gotelli and N.J. Sanders. 2005. The effects of fire, local environment and time on ant assemblages in fens and forests. Diversity and Distributions 11:487-497.
  • Rees D. M., and A. W. Grundmann. 1940. A preliminary list of the ants of Utah. Bulletin of the University of Utah, 31(5): 1-12.
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  • Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133
  • Ward P. S. 1987. Distribution of the introduced Argentine ant (Iridomyrmex humilis) in natural habitats of the lower Sacramento Valley and its effects on the indigenous ant fauna. Hilgardia 55: 1-16
  • Wetterer, J. K.; Ward, P. S.; Wetterer, A. L.; Longino, J. T.; Trager, J. C.; Miller, S. E. 2000. Ants (Hymenoptera: Formicidae) of Santa Cruz Island, California. Bulletin of the Southern California Academy of Sciences 99:25-31.
  • Wetterer, J.K., P.S. Ward, A.L. Wetterer, J.T. Longino, J.C. Trager and S.E. Miller. 2000. Ants (Hymenoptera:Formicidae) of Santa Cruz Island, California. Bulletin of the Southern California Academy of Science 99(1):25-31.
  • Wheeler G. C., and J. Wheeler. 1986. The ants of Nevada. Los Angeles: Natural History Museum of Los Angeles County, vii + 138 pp.
  • Wheeler W. M. 1915. Some additions to the North American ant-fauna. Bull. Am. Mus. Nat. Hist. 34: 389-421.
  • Wilson, E.O. 2003. Pheidole in the New World: A Dominant, Hyperdiverse Genus. Harvard University Press