Other Common Names
"curticornis complex" (clausa, curticornis, perplexa, & rubida)
Identification
See the key on page 99 of Camras
(1)(1953)...and, in particular, the table on pg. 102 of that reference...for details on separating the four taxa in this species complex.
Range
clausa: Transcontinental (Maine to Georgia, west to Washington and California...the only species in the complex present east of the Rockies);
curticornis: Western (Arizona, California, Colorado, Idaho, Oregon, Utah, Washington, and Wyoming);
perplexa: Western (Arizona, California, Idaho, Oregon, and Washington);
rubida: Western (California, Colorado, Idaho, Nevada, Oregon, Utah, Washington, and Wyoming)
Remarks
"[The species M. curticornis] is considered the basic species from which the others in this complex (M. rubida, M. clausa, and M. perplexa) are derived. Intermediates occur between all of these species, and at one time I felt that they should be considered one greatly variable species. However, the differences between the female genital plate characteristic of one species, without any intermediates, and the presence of different forms in the same regions without, intermediates, support the contention that we are dealing with distinct species in spite of the occasional occurrence of intergrades."