Species Pseudomasaris zonalis

P. zonalis albopictus R.M. Bohart (1950) forms with whitish markings (description)

Pseudomasaris zonalis (Cresson 1864)

Females: Color is black and sulphur-yellow (whitish in some forms, especially in the northeastern part of its range), frons with a pale spot above clypeus (may be missing in some specimens). P. zonalis can be recognized by humeri with an obtuse anterior ridge. Specimens where this ridge is weak may resemble marginalis The latter is more pubescent, and has a lamellate propodeum; if teeth are present, they're even shorter than in zonalis).

Though somewhat similar to P. edwardsii (also having humeri with an obtuse anterior ridge), female zonalis are lacking the 'bump' on mesotibia, characteristic for female edwardsii.

P. zonalis can be separated from the larger P. coquilletti by humeri with an obtuse anterior ridge vs. rounded in coquilletti.

Propodeal spines in zonalis usually shorter than in coquilletti and edwardsii; the yellow of upper orbits is not produced toward ocelli.

Males: smaller than coquilletti, with mid-tibia anteriorly emarginate; antennal club better defined, and obviously wider than segment 7:

see Richards (1963, 1966)

w NA (BC―CA to ID―CO)

Basically a mountain dweller, provided Phacelia flowers are present. Of 103 specimen examined by O.W. Richards (1963; see reference below), 47 were found at high altitudes (10,000 - 12,000 ft./ ~3000 - 3600 m), the remainder mostly from 6,000 ft.(~1800 m) or higher. At least one record exists from below 1,000 ft.(~300 m): Mitchell Canyon, Contra Costa County, CA; May 1961, on Phacelia nemoralis Greene.

Mostly May to August, depending on altitude and flowering of food plants.

Males feed on nectar of plants frequented by females. Females gather pollen and nectar to provision nest cells for offspring.

Plants used: mostly Phacelia (Boraginaceae, formerly in Hydrophyllaceae).