STATE PLANT BOARD 
August 1952 E-844 
United States Department of Agriculture 
Agricultural Research Administration 
Bureau of Entomology and Plant Quarantine 
NOTES ON LYCTIDAE (COLEOPTERA) 
By Ross H. Arnett, Jr. 
Division of Insect Detection and Identification 
That the family Lyctidae, the false powder-post beetles, is of 
economic importance is indicated by the numerous times these small 
beetles are encountered in various manufactured goods, such as ax and 
hammer handles, baskets, and furniture, as well as in buildings and in 
herbs and roots. 
Recently two species, Lyctus prostomoides Gorham and L. impressa 
Comolli, have come to my attention as intercepted and imported pests. 
Although there is no evidence that they have become established in this 
country, they may have gone unrecognized as " Lyctus sp." Another species 
L. villosa Lesne, was sent in for identification recently, and from the 
data accompanying the specimens, as well as from additional specimens 
in the U. S. National Museum collection, it appears that this species may 
have become established in this country, but has not yet been recorded in 
the literature. Therefore, a few notes on the distinctive appearance of 
these species, their hosts and distribution, may call attention to their 
presence in this country, either in existing collections or in those made 
in the future. 
There is some controversy over the proper generic placing of the first 
two species mentioned above. The current catalog (Lesne _7, pp. 14-16) 
places them in the genus Trogoxylon LeConte (_5, p. 209). The validity of 
the separation of this genus from Lyctus Fabricius (2, p. 502) is question- 
able. LeConte's separation was on the basis of the structure of the 
anterior tibiae (viz., anterior tibia with the outer apical angle not pro- 
longed in Trogoxylon and prolonged in Lyctus) . This character has since 
been shown not to be constant for the species which LeConte included in 
the genus. In the original description of the genus the genotype of 
Trogoxylon was designated as the species Xylotrogus parallelipipedus 
Melsheimer (8, p. 112). This designation gives us a basis for a definition 
of the genus. The group that LeConte considered as constituting this 
genus corresponds roughly to Kraus's (_4, pp. 116-118) group of species of 
Lyctus with confused pubescence and confused or somewhat striate elytral 
punctation. These species may or may not form a natural group but these 
