Stenostrophia tribalteata subsp. sierrae Linsley & Chemsak, 1976

Two Pacific Northwest subspecies: tribalteata serpentina (Casey, 1891:41) and tribalteata sierrae Linsley & Chemsak, 1976:113. Subspecies serpentina (left image) ranges through the Rocky mountains from British Columbia to Wyoming and Nevada. Subspecies sierrae (right image) can be found from the central Oregon Cascades to southern California. The two populations appear to come into close contact in the central Oregon Cascades (see map, Fig. 28 in Linsley and Chemsak, 1976, p. 112).

The nominal subspecies, S. tribalteata tribalteata (LeConte, 1873), only occurs on the eastern slopes of the Sierra Nevadas, and ranges into central Nevada. 

Above left: subspecies serpentina, with typical pale antennae and weaker median bands of the elytra.
Above right: Stenostrophia tribalteata sierrae. Notice that the yellow bands on the elytra are slightly thinner than the black bands.  

History 

The "subspecies" of tribalteata have a somewhat complicated nomenclatural history, as different authors have treated tribalteata ​(LeConte) and serpentina (​Casey) as either two distinct species, or "aberrations" of the same. The species have also been listed under several genera. A full review and bibliography of the history of names applied to ​this group is presented by Linsley and Chemsak (1976, p. 111).  The following is a brief summary with reference to the more notable authors:  

Casey (1891) originally described Leptura serpentina from Idaho as a species distinct from tribalteata (type locality: Owen's Valley, California). Casey however was notorious for naming specimens based on very few specimens and soon thereafter, Leng and Hamilton (1896) decided that Casey's serpentina was merely a synonym of a variable species tribalteata (LeConte). Casey (1913) again treated the species as distinct when he described the genus Stenostrophia, commenting, "serpentina has been hastily united with tribalteata, but it is a valid species, differing greatly in the structure of the antennae, particularly those of the male, where those organs are long, slender and filiform, being scarcely at all shorter than the body and are constantly testaceous in color throughout; in tribalteata they are much thicker, shorter, more compact, differ less sexually and are always deep black in color." Horning and Barr (1970) recognized tribalteata and serpentina as distinct species, though within the genus Anoplodera. Melville Hatch (1971, p. 130, pl. 14, fig. 7) recognized only one species, A. tribalteata.  Linsley and Chemsak (1976) returned the species to Stenostrophia Casey, and were the first to introduce the concept of serpentina and tribalteata as subspecies, to which they also added the subspecies sierrae. Linsley's subspecies concept is elaborated in Mayre, Linsley and Usinger (1953). Though it is probably equally as acceptable to refer to these forms as full species, I have retained L&C's system until such time that a more thorough investigation can be made of the internal morphology and biology of the species complex. 

References

1. Casey, T. L. 1891. Coleopterological notices III. Ann. New York Acad. Sci., 6:9-214. <PDF at Biodiversity Heritage Library>
2. Casey, T. L. 1913. Further studies amongst the American Longicornia. Memoirs on the Coleoptera, 4:193-388. <PDF at Biodiversity Heritage Library>
3. Hatch, M. 1971. The beetles of the Pacific Northwest. Part V. Rhipiceroidea, Sternoxi, Phytophaga, Rhynchophora, and Lamellicornia. University of Washington Publications in Biology, 16.
4. Horning, D. S. jr. and W.F. Barr. 1970. Insects of Craters of the Moon National Monument. Id. Univ. Coll. Agric. Res., 11: 371-383. 
5. LeConte, J. L. 1873. New species of North American Coleoptera. Prepared for the Smithsonian Institution. Part II. Smithsonian Miscellaneous Collections.  11(264):169-240. 
6. Leng, C. W. and J. Hamilton. 1896. The Lamiinae of North America. Transactions of the American Entomological Society, 23: 101-178. <PDF at BHL> 
7. Linsley, E.G. and J.A. Chemsak. 1976. Cerambycidae of North America. Part VI, No.2. Taxonomy and Classification of the Subfamily Lepturinae. University of California Publications in Entomology 80, 186 pp. 
8. Mayer, E., E.G. Linsley and R.L. Usinger. 1953. Methods and Principals of Systematic Zoology. McGraw-Hill Book Company, Inc., New York, Toronto, London. 336 pages.