Floyd G. Werner

ANTHICIDAE OF THE GREATER ANTILLES, AND A NEW SPECIES FROM VENEZUELA (COLEOPTERA)

Thirteen of the 29 species that are known or reported from the Greater Antilles appear to be endemic. Five (Anthicus darlingtoni, hispaniolae, macgillavryi, soledad and subtilis) make up the subtilisgroup, which does not seem to have near relatives on the mainland. Three others stand quite isolated in their genera: Acanthinus schwarzi in an almost exclusively neotropical genus, Anthicus blackwelderi and russoi in a world-wide genus that contains many diverse elements. A. blackwelderi is counted among the endemic species because it has different color patterns on the islands that it is known to inhabit; the form of the internal sac of the male genitalia is very different from that of possible relatives on the mainland. A. russoi is probably not properly placed in Anthicus, and is unlike any anthicid known to me in several details; Menozzi’s (1930) evidence that it is a myrmecophile with a native ant makes local origin seem logical. The 5 other endemic species are similar to mainland New World species. Mecynotarsus hispaniolae and jamaicanus belong to the elegans-group, which has species from Florida to Central America. Notoxus bipunctatus and jamaicus have been assigned to the monodon-group (Chandler 1978), which ranges from Canada to northern South America. Finally, Anthicus antilleorurn seems to have originated in the Greater Antilles and spread to the Virgin Islands and Bahama Islands; its nearest relatives are found around the southern Caribbean.

ENZYME VARIATION IN SEMI-ISOLATED POPULATIONS OF THE MOUNTAIN FLY CHAMAEMYIA HERBARUM

Chamaemyia herbarum (Robineau-Desvoidy) is an acalyptrate fly in the family Chamaemyiidae. In southern Arizona, C. herbarum larvae prey upon one or more species of mealybugs (Trionymus spp.) which infest the bunch grass Muklenbergia virescens (H.B.K.) Kunth. The fly overwinters in the pupal stage and two to four generations are completed during summer breeding seasons. It is restricted to small, isolated populations within the pine forest or transition zone (Merriam, 1890). Adult populations in mountain meadows are small, from approximately 50 to 1,000 individuals, and are separated from each other on the same mountain by stretches of meadowless pine forest. The dispersal ability of the species is not known. Adults have been observed moving toward the base of grass clumps during windy periods. Such behavior would limit passive wind dispersal, the most likely means of movement between mountain ranges. The center of distribution of C. herbarum is in the Rocky Mountains of the western United States and the southernmost extension of its range is in the southeastern mountains of Arizona. Populations in the Colorado Rockies may be classified as semi-isolated; the proximity and continuity of the mountain ranges may allow limited migration between populations or subpopulations. In Arizona and northwestern New Mexico, each population is restricted to a separate mountain range and may be a geographic isolate. Although the species is restricted to the same pine forest zone across its range, populations are located within different biotic provinces (Dice, 1943). These provinces are based upon differences in floral composition; however, they also reflect faunal species boundaries. Grasses of southern Arizona mountains support mealybug species not found farther north. The specific grassmealybug associations are not available for C. herbarum; therefore, a comparison between isozyme frequency differences and biotic provinces may define possible genotype-environment interactions. The purpose of our study is to evaluate the importance of geographic isolation, small population size, founder effect, and ecological adaptation to the differentiation of C. herbarum populations. Genetic differences between populations were determined by multiple loci starch gel electrophoresis. A morphological analysis of metric characters was conducted to estimate further population variation.

A New Genus and Species of AnthicidaeFrom Western United States

The first specimen of the inter,esting beetle described here was taken by Dr. W. L. Nutting and the author under dried flakes of mud .on an alkali flat in Nevada in 19.50. A diligent search in this rigorous habitat resulted in our obtaining one specimen alive, another dead and broken up, a living and a dead specimen of Tanarthrus salinus Lec. and one or two living spiders. There was evidence of other insects, present mostly as fragments. Most .of these seemed to. belong to gr,oups that would have blown in from surrounding areas. A second living specimen was taken by H. B. Leech in sand dunes near Stovepipe Wells, in Death Valley. The two collections indicate a rather extensive range for the species in the West, possibly confined to .extreme desert areas. Despite the shortened elytra, this insect is quite ,obviously an Anthicid. On first appearance it might be linked with such an insect as Ta,narthrus brevipennis Csy., a species which also has abbreviated elytra. There are several striking points, of difference. The present insect is much more slender than any known species .of Tanarthrus. It has the last segment of the antennae entire and normal, without the groove that gives the illusion of dividing the last segment into two in Tanarthrus. There are major ,differences in the internal sac of the male genitalia. All the species ,of Tanarthrus except T. salinus have been examined and they have heavy spines, .on the internal sac and lack any specialized armature around the gonopore. The present insect lacks spines .on the internal sac and has a peculiar structur,e associated with the gonopore, completely unlike any found elsewhere in the family, at least as it is represented in North Ameri.ca. The general shape of the genitalia is similar in the two genera. It seems

Two New Species of Emelinus From Arizona (Coleoptera: Aderidae)

The two species of Emelinus described here bring the known species in .our fauna to. four. Others assignable to the genus have been described from Central and South America but, s.o far, none from the Old W.orld. Since the last general work on Nearctic species of Aderidae, by Casey in 1895,e there has been only one significant publication affecting our fauna, a reclassification on a World basis by Baguena Corella in 1948. Whereas neither Pic nor Champion felt that the genera set up by Casey could have more than subgeneric or species-group significance, Baguena Corella has made an effort to split up the huge and diversified assemblage .of species already assigned to Xylophilus or Hylophilus, raising Emelinus not only back to generic rank but setting it off in a separate tribe, Emelinini. Baguena Corella also shows good reason for using the family name Aderi.dae, thus ending a triple tie for the names Euglenidae, Xylophilidae and Hylophilidae. Baguena Corella’s definition of Emelinus restricts it to species with the head totally visible from above and with the male antennae flabellate from the fourth segment. The two new species fit this diagnosis but differ in some details possibly .of generic significance from E. melsheimeri (Lec.) and E. ashmeadi Csy. In these the antennae angle beyond the third segment in the male and the rami .of segments six through ten .originate near the apex of the segments. The two species from Arizona do