INTRODUCTION 
The family Polyctenidae comprises a small assemblage of ectoparasites 
of bats. It is comparable in number of species to such small families as the 
Leptopodidae and Mesoveliidae but individuals are less common than in 
either of these semiaquatic groups, less than one hundred specimens of the 
family having been accumulated in the insect collections of the world. 
However, a fairly wide sampling of geographical areas has been achieved. 
It still remains for a hemipterist particularly interested in these bugs to 
collect and observe them alive in the field. Despite this lack of biological 
information and despite the small sampling and absence of positive knowl¬ 
edge as to the limits of variability, host specificity and related matters, a 
rather large fund of information has been accumulated. Out of this has 
emerged a remarkably complete picture of this unique group of Hemiptera. 
History . First described by Giglioli in 1864, Polyctenes molossus was 
placed in the dipterous family Nycteribiidae. The name was originally 
suggested to Giglioli by J. O. Westwood who followed, ten years later, with 
a monumental work in which he proposed the family Polyctenidae and re¬ 
ferred it to the order Anoplura. Waterhouse soon transferred the group 
back to the Diptera and then, one year later, first suggested its hemipterous 
affinities. It was left in the Diptera, however, for the next twenty-four 
years until Speiser reviewed its systematic position in 1904 and placed it 
near the bed bugs where it remains to this day. 
By this time much confusion had crept into the literature because of the 
failure of entomologists to recognize the immature forms. Kirkaldy brought 
order out of the chaos in 1906 with a very brief but sound classification of 
the group into four genera. Horvath then became interested in the group and 
described several genera and species, most of which proved to be synonyms. 
The modern era in Polyctenid systematics really began with Jordan’s 
comprehensive review of the old world species in 1911. Jordan used the 
microscopic technique developed in the course of his studies on fleas and 
other ectoparasites. In a series of papers he did much to clear up doubtful 
forms and made known several exceedingly interesting new genera and 
species. It was Jordan who first suggested the remarkable type of viviparous 
reproduction which Hagen (1931) studied so thoroughly. Contributions by 
Ferris, Schwenck, and a catalogue by da Costa Lima (1920) practically 
completed work on the group until the monograph by Ferris and Usinger in 
1939. This last work was prompted by the accumulation of more material 
than had ever been assembled before and was greatly facilitated by the 
cooperation of hemipterists and parasitologists in various parts of the world. 
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