Dy MISC. PUBLICATION 341, U. S. DEPT. OF AGRICULTURE 
Field work and rearing experiments show that the white-fringed 
beetle reproduces by parthenogenesis, a rare phenomenon among 
beetles in general, but one of commoner occurrence in the Curculioni- 
dae than was formerly supposed. Several other introduced species 
of weevils treated in this publication are known or strongly suspected 
to be parthenogenetic, and the same mode of reproduction has been 
demonstrated for a few introduced species of two other genera, 
among them the vegetable weevil (Léstroderes obliquus Klug) and 
the alfalfa snout beetle (Brachyrhinus ligustict (.)). That these 
foreign pests have succeeded in establishing and maintaining them- 
selves, often in the face of vigorous control measures, indicates that 
parthenogenesis is an important predisposing factor to the likeli- 
hood of dispersal and to potential destructiveness, the ability of any 
specimen to start a new colony and the accelerated rate of reproduc- 
tion evidently being advantageous to their possessor in the contest 
to survive and to occupy new territory.. It may be mentioned that, 
so far as known, all parthenogenetic species of Curculionidae are 
flightless.° i 
The white-fringed beetle (fig. 1, A) was first described by Boheman 
in 1840 as Naupactus leucoloma. It belongs to the Pantomorus- 
Naupactus complex, which includes 240 or more named species, all 
indigenous to the New World. Of these about 193 are natives of 
South America and about 45 of Mexico or Central America. At 
present the majority of the South American species are cataloged in 
Naupactus, most of the others in Pantomorus. This publication deals 
with the taxonomy of the 14 species and varieties now known from 
the United States; all these, for reasons stated later, are assigned 
to Pantomorus. 
Pantomorus is a relatively natural group but Nauwpactus is hetero- 
geneous and some of its species will have to be transferred to Pan- 
tomorus or to other genera. Sharp and Champion * were perhaps the 
first to recognize adequately the broad scope of Pantomorus, and its 
close affinity with Maupactus,; they separated the two genera chiefly 
by the absence of wings and well developed humeri in Pantomorus 
and their presence in MVaupactus. These are the best distinguishing 
characters yet discovered, though they are often difficult to use and they 
nearly fail in two or three South American species which have wings 
intermediate in size between the rudimentary and the fully developed 
forms. There is little doubt that the Pantomorus-Naupactus series 
eventually will be reclassified along lines other than those based on 
wing characters, but until all the species can be critically studied the 
wing and humeral distinctions must be used for dividing the entire 
complex into two vaguely defined genera, Vaupactus and Pantomorus. 
All the species from the United States are flightless and are therefore 
placed in Pantomorus; they form, however, four rather distinct 
segregates which are here called subgenera. 
Little is known in detail of the biologies, but it is probable that all 
the species of both Pantomorus and Naupactus are root feeders as 
2 WILcox, J., MOTE, DON C., and CHILDS, LPROY. THE ROOT-WEEVILS INJURIOUS TO 
STRAWBERRIES IN OREGON, Oreg. Agr. Expt. Sta. Bull. 330, 109 pp., illus. 1934. See 
Pp. ATS: for a summary of data on parthenogenesis in the genera Brachyrhinus and 
yslobus. ‘ 
SMITH, FLOYD F. BIOLOGY AND CONTROL OF THE BLACK VINE WEEVIL. U. S. Dept. 
Agr. Tech. Bull. 325, 46 pp., illus. .1932. See pp. 20-21. 
3 SHARP, DAVID, and CHAMPION, G. C. BIOLOGIA CENTRALI-AMERICANA. INSECTA. 
COLEOPTERA. vy. 4, pt. 3, 354 pp., illus. 1889-1911. 
