In view of the preliminary nature of this paper, the key to the species is given here. Because it is one of the largest and easiest to recognize of the species originally included here. Horn pointed out the open anterior coxal cavities as the defining characters of the genus.
Because of the difference in the male and female claws, Weise has placed Monoxia in the subfamily Apophyliini, a group consisting of African and Asian genera and far removed from Galerucella. Apart from its family resemblance, the only similarity of Monoxia with the other genera of the subfamily Apophyliini is the difference in. A STUDY OF THE GENUS MONOXIA — BLAKE 147 the claws of the sexes in the majority of the species, and its inclusion in this subfamily is purely artificial.
As in Galerucella, there are often traces of one or two raised lines on the inner part of the elytra, parallel to the suture and especially visible on the basal half. Furthermore, the abdomen of the male in most specimens is not as indented as in other species. Among the medium-sized species it is distinguished by the coarse elytral punctation.
The most striking feature of the guttulate, which distinguishes it from other large species, is that it is long and somewhat upright.
A STUDY OF THE GENUS MONOXIA — BLAKE 155 MONOXIA SORDID A (LeConte)
The shape of the prothorax places this species, together with two hitherto undescribed species, apicalis and brisleyi, in a distinct group. These three have another point in common — the claws are not simple in the female, as in most species of Monoxia, but have a small tooth, which raises them. The abdomen of the male does not appear as forked as in most species of Monoxia.
The only other species of the genus known to the author which has this last characteristic is the eastern M. Some specimens are entirely pale or with only faint reddish-brown spots, while others are heavily and darkly marked. Some Arizona specimens are also large and very dark, while others are small and pale and resemble the Colorado Desert species.
While the general shape of the aedeagus remains the same throughout, there is considerable variation in this structure even in a series from a single locality.
A STUDY OF THE GENUS MONOXIA — BLAKE 157 LeConte's Latin description of Galleruca angularis may be translated
LeConte gave as a distinguishing mark of this species the prominent posterior angles of the prothorax, a character usually expressed in this species. This prominence of the basal angles is mainly due to the breadth of the prothorax, together with the exceptionally well-developed teeth and the deep curvature below the tooth at the basal border. The prothorax is broader than in many species, being nearly twice as long and covered with short, sharp pubescence.
The elytra are broadly elongate, with a short intrahumeral depression, but this is not as long or as pronounced as in guttulataor conspuia, and the punctation is not as shallow as those two species. In addition to having rather prominent basal angles of the prothorax, it is further distinguished by being one of the largest species, varying in length from 4.5 to 5.3 mm. Along the Pacific coast, from California to British Columbia, specimens have elytral pubescence rather sparse, closely acute and inconspicuous, with punctation subconspicuously visible.
Specimens from eastern Washington (Elk, Pullman, Ritzville), on the other hand, have moderately dense elytral pubescence, and the prothorax not so depressed at the sides. Specimens from Idaho, Montana, Wyoming, Utah, and Colorado have even denser elytral pubescence, almost obscuring the punctation below. In these the prothorax appears wider and less depressed at the sides, with the basal angles more prominent.
In all specimens examined from different localities, the aedeagus is similar in being long, curved and. The tip, however, in specimens from eastern Washington, Idaho, Montana, Utah, and Colorado is broader than in specimens from the Pacific coast and somewhat wedge-shaped. It is possible that with a more complete scope of their biology, specimens from the eastern part of their range may represent one or more distinct subspecies.
A STUDY OF THE GENUS MONOXIA — ^BLAKE 159
The elytra are very small, and those of the subsutural series usually merge, forming a narrow, foreshortened line; the humerus are prominent and marked with a larger black spot. Three of these four are undoubtedly the same species as the first, but one, a male, which is more slender and less densely punctured and hairy, belongs to a different species. The one with the label and the two similar males are the same color.
The female has darker markings - prothorax. has two lateral spots and a median stripe that unites anteriorly to form an M-shaped figure, and the elytra have the suture dark, and the spots coalesce in places to form interrupted vittae and the undersurface. is almost dark except for the last abdominal segments. In the paler male specimens, the prothorax is unmarked or only weakly marked, the elytra have less contiguous spots, and the mesosternum, metasternum and first abdominal segments are partially darker. The head in all four is without prominences; the median line is not. very impressed; the pubescence is dense but not long and covers the occipital puncture; the color is pale, deeper on the occiput, but the labrum and median line are dark. slightly darker reddish brown and thicker outer joints.
The prothorax has well-rounded sides and is not too depressed in the middle and at the sides; the basal tooth is small; pubescence is. dense but not long, obscuring the dense point below. elytra are convex with only ashortintrahumeral depression and have deep and rough punctures, but distinct and not united, becoming. finer and shallower at the top. Testaceous, with pale pubescence, prothorax strongly and densely punctate, less than twice the entire length, with rounded sides, posterior angles acute, with a small tooth at apex, disc channeled and in both sides broadly impressed; elytra densely punctate, punctures stronger anteriorly; outer edge of antennae and thorax and abdomen infuscate.
A STUDY OF THE GENUS MONOXIA — ^BLAKB 161
Large (about 4.5 mm.), broadly oblong-oval, pale yellow-brown, often without elytral markings or with only pale reddish-brown traces of subsutural vitta and darkened humeri, under surface usually more or less dark; pro thorax not twice as wide, with posterior angles not pronounced and sides not much narrowed anteriorly;. Prothorax more rectangular in shape than indebilis, but not twice as wide as long, and with the sides not very curved and not much narrowed anteriorly; the disc is more depressed in the middle and on the sides than in debilis, the basal angles tend to be smaller than in debilis, and with duller basal teeth;. Elytra with intrahumeral sulcus not marked; punctuation dense, tending to be confluent, shallow and coarse and not completely hidden by the long but not dense pubescence; color often entirely pale or with pale reddish-brown traces of subsutural vitta and darkened humeral spot, occasionally the latter extending down the sides.
A STUDY OF THE GENUS MONOXIA - BLAKE 163 and in having a shallow elytral piction and differing from guttu-.
A STUDY OF THE GENUS MONOXIA — BLAKE 163 and in having shallower elytral pimctation, and it differs from guttu-
Medium-sized (about 4 mm), elongated, moderately convex, with a broad head and a narrow and not very sunken prothorax; sometimes quite pale, again with the prothorax and elytra darkly marked and the underside more or less darkened; densely covered with short, fine pubescence, and rather finely and shallowly punctured. Prothorax not twice as wide as long and not much wider than the head, with curved, sometimes angular sides, and a small tooth in the basal angle; not much. Body covered below with fine hair; sometimes pale, sometimes speckled beneath the surface and legs.
Paratypes also in the collection of the Museum of Comparative Zoology, Cambridge, Massachusetts, and the California Academy of Sciences, San Francisco, California.
A STUDY OF THE GENUS MONOXIA — ^BLAKE 165
H. Hatch, and Ralph Hopping
Remarks.—This slender, pale, medium-sized species, apparently abundant in western Texas, Arizona, and New Mexico and extending north to Alberta, is distinctive in being one of the least pubescent of the genus. Medium size (about 4 mm.), slender, pale yellowish brown, usually with darker reddish brown humeral spot and traces of subsutural vitta, sometimes heavily marked with spots and lateral infuscation;.
A STUDY OF THE GENUS MONOXIA — BLAKE 167
Elytra broadly elongate, convex, with a short intrahumcral sulcus, rather thickly and densely pimctate and covered with dense, pale, sometimes erect pubescence; usually with some minor marks. Body subpubescent fine, pale, with metasternum and sometimes first abdominal segments dark. Distribution.-Colorado (Denver, Florence, FortCollins, GrandJunc-. tion, Hotchkiss, La Veta, Kocky Ford); Idaho (Blackfoot, Parma).
A STUDY OF THE GENUS MONOXIA — BLAKE 169
A small series from LosAngeles, California appears to be somewhat more coarsely punctate than typical and the aedeagusis to be slightly wider. The head is densely punctate and slightly pubescent, with an impressed median line and a slight callus. Prothorax fully twice as long as long, with sides slightly rounded and with a small tooth in basal angle; disk broadly impressed at sides and.
Elytra somewhat depressed, with an intrahumeral depression extending below and in about one-third the length of theelytra; densely and distinctly punctate, pubescence moderately long but not at all obscuring the punctation; Heavy dark markings usually predominate over pale, pattern similar to distinguished specimens of M. It is a much smaller species than guttulata and belongs to a different group, being closely related to M. It has a prothorax of short and broad in similar shape, and the claws are toothed in both sexes, as in sordida.
A STUDY OF THE GENUS MONOXIA BLAKE 171
