Explanation of Names
PTILIIDAE: from the Greek "ptilon" (feather) - a reference to the feather-like hindwings, and the origin of the common name, Featherwinged Beetles.
Numbers
Nearctica.com lists 113 species in 28 genera in North America
U. of Florida states there are 115 species in 23 genera in North America
Size
the smallest known beetles, most species being 1 mm or less in length and the smallest known being 0.35mm
Identification
minute size, hindwings with feathery filamentous fringe of hairs (usually hidden beneath elytra in live individuals, and often protruding beyond elytra in pinned museum specimens)
Many species exhibit striking polymorphism, in which each sex is represented by two forms:
1. a normal morph with well-developed eyes, wings, and body pigmentation
2. a vestigial morph in which eyes, wings, and body pigmentation are reduced or lacking
The vestigial morph is the more abundant form, comprising 90% or more of all individuals
Range
Widely distributed in temperate and tropical regions of the world
Habitat
leaf-litter on the ground, decaying logs, compost heaps, treeholes, decaying fungi, animal dung, under bark, sea weed on sea shores, and in other moist organic materials
Food
larvae and adults feed on molds and fungi
Life Cycle
Reproduction occurs continuously under favorable conditions; larvae often are found together with both teneral and fully-hardened adults at different times of the year; only a single egg is accommodated and matured in the abdomen at a time, and this egg is nearly half the female body length.
Remarks
Ptiliidae have an unusually high incidence of thelytokous parthenogenesis (the production of females from unfertilized eggs). In Florida, five of seven species in the pantropical genus Bambara are known from females only.
Print References
American Beetles, Vol. 1, Chapter 17
(1)Internet References
adult images plus description, numbers, habitat, distribution, biology, and references [courtesy of Henry Drybas, Field Museum of Natural History, Illinois] (Featured Creatures, U. of Florida)
