Synonyms and other taxonomic changes
Syn: A. parallelus Horn 1872
Explanation of Names
Attalus rufiventris Horn, 1872
Identification
highly variable, often with a red or nearly all red head and pronotum, elytra flat colored and distinctly not parallel-sided
"This species
varies in its coloring to a greater extent than has been indicated by previous authors, so much so that the limitation of the species and its satisfactory placement in any key become difficult matters. Even after we agree that Fall (1917) was correct in placing
A. parallelus Horn as a synonym of
A. rufiventris, the variation
described by Horn (1872), in which the "occiput and narrow median thoracic stripe (are) black," by no means exhausts the possibilities.
In a series of 90 specimens, from various points in Texas, southern New Mexico, southern Arizona, and southern California,
only seven are typical A. rufiventris with the thorax and head entirely red and these are all females. Of all the others which have the elytra typically colored, with only a narrow sutural margin and the apices red, 21 in number, represent Horn's 'variety,' noted above and are all males except one, showing that this variation is mainly sexual in character. In some the thoracic stripe is abbreviated, forming a median anterior thoracic spot. In many the black color of the occiput extends for a variable distance down the fronts in some reaching the clypeal suture. In most of those which have the lower portion of the front yellow, the pale color forms a transverse band above the clypeus, but in a few it forms a definitely trilobed frontal area, as in several other species.
Ten of the specimens, from southern Texas and southern California, have the elytra quadrimaculate and are Horn's
A. parallelus. The remaining specimens, which constitute the
majority of the entire series, show all degrees of intermediate stages between the elytral coloring of the typical specimens and the quadrimaculate form. Some show an elytral pattern resembling
A. trimaculatus, but these may be distinguished from
A. trimaculatus, in addition to the short head, by the fact that the apical spots always attain the lateral elytral margins.
In the southern Arizona specimens, twelve in number, from Tucson and Wickenburg, the basal portion of the pale sutural margin tends to become widely dilated, forming a red triangle whose sides extend from the elytral humeri to a point near the apex of the suture. In the extreme forms of this variation, the scutellum is also entirely pale.
In a series of ten from southwestern New Mexico (Hidalgo County), the abdomen is more or less heavily maculate with black, in the majority being entirely black, with the borders of the segments pale, thus belying the specific name.
A series of nineteen specimens from the Santa Rosa Mountains, in southern California, appear to be typical
A. rufiventris, except for a strong tendency to the quadrimaculate form, eight of the ten of such forms mentioned above occurring in this series. The scutellum in all of these specimens, however, remains black whereas in typical
A. parallelus from southern Texas, it is testaceous.
Specimens of the quadrimaculate form, from Prescott, Arizona, received after the above notes were made and which are associated with typical
A. rufiventris have two black dots on the prothorax, of variable size, arranged as in
Collops bipunctatus.
It is possible that I have included more than one species in this lot of material and, in fact, I have separated two forms from the original confused lot, presently to be described as new, largely on the basis of characteristic modifications of the genital segments. With these exceptions, however, intermediate examples appear to be present to connect all the extremes noted. It seems that this species is in a state of active evolutionary change at the present time and is splitting up into several derivative forms, which are not as yet sufficiently isolated or distinct to be defined as sub-species. I believe that we can best obtain a concept of such species by carefully noting the extent and the locale of the variations in such series as it has been my privilege to examine. (emphasis added)
(2)Range
s.CA-e.TX, UT / n. Mex. (BAJA-SON)
(2)(3), mostly OK to s.TX
See Also
Attalus subtropicus Marshall - elytra shiny and nearly parallel-sided, back of head black and wide pronotal stripe always present
- uncommon and resticted to s. TX (as far n. as Bexar Co.)
Det. E. G. Riley, 2010
Attalus trimaculatus (Motschulsky) - Range: CA-AZ
Attalus tucsonensis Marshall - Range: CA-AZ
Print References
Fall, H.C. (1917) Short studies in the Malachiidae. Transactions of the American Entomological Society, 43: 67-88.
Horn, G.H. (1872) Synopsis of the Malachiidae of the United States. Transactions of the American Entomological Society. 4: 109-127. (
Full Text)
Marshall, M.Y. (1951) Studies in Malachiidae, III. Proceedings of the California Academy of Sciences, 27: 77-132. (
Full Text)
