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Family Ptiliidae - Featherwing[ed] Beetles

tiny ptiliid - Acrotrichis tiny ptiliid - Acrotrichis Tiny bristle-antennaed beetle - Ptenidium New Smallest Beetle !!!    (for bugguide, me) Fir Feather-wing - Pteryx Featherwing Beetle - Acrotrichis Ptiliidae Acrotrichis? - Acrotrichis
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
No Taxon (Series Staphyliniformia)
Superfamily Staphylinoidea (Rove, Carrion and Fungus Beetles)
Family Ptiliidae (Featherwing[ed] Beetles)
till EE ih dee
Explanation of Names
Ptiliidae Erichson 1845
Greek ptilon 'feather' (refers to the feather-like hind wings)
3 subfamilies, with ~120 spp. in 27 genera in our area, 550 described spp. in ~70 genera worldwide; significant numbers of undescribed taxa have been collected(1)(2)
Overview of our faunaTaxa not yet in the guide are marked (*); classification follows(3)
Subfamily Acrotrichinae
Subfamily Ptiliinae
the smallest known beetles, most species being under 1 mm, and the smallest known being 0.35 mm
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(4):
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
Widely distributed in temperate and tropical regions of the world
moist organic materials, incl. leaf-litter, decaying wood, compost, treeholes, fungi, seaweed, dung, under bark, etc.(4)
throughout the year
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 (nearly half the female body length) is accommodated and matured in the abdomen at a time. Many spp. produce females from unfertilized eggs (thelytokous parthenogenesis), in which case populations may be female-only(4)