Pheidole californica

Wilson, E. O., 2003, Pheidole in the New World. A dominant, hyperdiverse ant genus., Cambridge, MA: Harvard University Press : 564-565

Pheidole californica Mayr

Pheidole californica Mayr 1870b: 987. Syn.: Pheidole oregonica Emery 1895d: 291, n. syn.; Pheidole californica var. incenata Wheeler 1915b: 407, synonomy by Creighton 1950a:173; Pheidole californica var. satura Wheeler 1915b: 407, synonomy by Creighton 1950a: 173; Pheidole californica subsp.pyramidensis Emery 1922c: 105 (replacement name for nevadensis Wheeler 1915b: 408, junior primary homonym ofpheidole nevadensis Forel 190 lj: 353), synonomy by G. C. and J. Wheeler 1986g: 18; Pheidole californica var. shoshoni Cole 1933b: 618, synonomy by Gregg 1959: 1-9; Pheidole californica var. hagermani Cole 1936a: 35, synonomy by Creighton 1950a:173.

Types Naturhist. Mus. Wien.

Etymology Based on the state of origin of the type series.

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

P. californica is distinguished within this complex 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.

Range California north to Washington, east to Idaho and New Mexico.

Biology 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 Leptothorax pergandei .

figure Upper: major. Lower: minor. CALIFORNICA: Palo Alto. Type locality: San Francisco. Scale bars = 1 mm.