Barklice
Guides
Psocodea
bark lice, book lice, parasitic lice, barklice, booklice
Psocodea is an order of insects comprising approximately 11,000 species across three extant suborders: Trogiomorpha, Troctomorpha, and Psocomorpha. The group includes free-living barklice and booklice, as well as the parasitic lice (formerly Phthiraptera). Molecular and morphological evidence demonstrates that parasitic lice evolved from within the barklice lineage, rendering the former order 'Psocoptera' paraphyletic. Members range from 1–10 mm in length and occupy diverse habitats from forest canopies to stored products.
Psocus
barklice
Psocus is a genus of barklice in the family Psocidae containing approximately 17 described species. The genus has been taxonomically redefined to exclude many previously assigned unrelated species. Psocus includes the largest known psocids and occurs naturally in Europe and North America.
Psoquillidae
bird nest barklice
Psoquillidae is a family of small insects commonly known as bird nest barklice, classified in the order Psocodea. The family contains approximately 8 genera and more than 30 described species. These insects are primarily associated with bird nests, where they inhabit the accumulated organic material. The family was established by Lienhard & Smithers in 2002.
Psyllipsocidae
Cave Barklice
Psyllipsocidae is a family of small psocid insects commonly known as cave barklice, comprising approximately 7 genera and more than 70 described species. The family belongs to the suborder Trogiomorpha within the order Psocodea. Members of this family have been recorded across multiple biogeographic realms including West Palaearctic, Afrotropical, Australian, Nearctic, Neotropical, and Oriental regions. Some genera, such as Dorypteryx, exhibit notably wide geographic distributions. Several extinct genera are known from Cretaceous amber deposits.
Psyllipsocus
Psyllipsocus is a genus of cave-dwelling barklice comprising more than 50 described species. Members of this genus inhabit dark, humid microhabitats including caves, rock crevices, and similar subterranean environments. The genus was established by Selys-Longchamps in 1872 and represents one of the most species-rich genera within the family Psyllipsocidae.
Pteroxanium
scaly-winged barklice
Pteroxanium is a genus of scaly-winged barklice in the family Lepidopsocidae, first described by Enderlein in 1922. The genus comprises approximately eight described species distributed across multiple continents. Members are characterized by their distinctive scaled wings, a trait that distinguishes them from many other barklice groups. The genus includes species found in both tropical and temperate regions, with records from the Americas, Europe, and insular localities.
Ptycta
barklice
Ptycta is a genus of barklice (family Psocidae) containing more than 150 described species. The genus was redefined based on the morphology of the male terminalia, specifically the forewing venation where veins Rs+M are fused for a short distance. Species occur across multiple continents including Asia, Australia, Africa, and the Americas. The genus is distinguished from the related Copostigma within the Copostigma–Ptycta complex by this wing venation character.
Ptyctini
common barklice
Ptyctini is a tribe of barklice in the family Psocidae, containing approximately 6 genera and at least 20 described species. Members are small, soft-bodied insects commonly found on bark, foliage, and other surfaces. The tribe was established by Mockford in 1993 and includes genera such as Ptycta, Steleops, and Trichadenotecnum.
Reuterella
damp barklice
Reuterella is a genus of damp barklice in the family Elipsocidae, established by Enderlein in 1903. The genus contains at least one described species, R. helvimacula. These insects belong to the order Psocodea, which includes barklice, booklice, and parasitic lice. Members of this genus are associated with moist microhabitats on bark surfaces.
Rhyopsocus
bird nest barklice
Rhyopsocus is a genus of barklice in the family Psoquillidae, commonly referred to as bird nest barklice. The genus contains more than 20 described species. These insects are associated with bird nests, where they feed on organic debris. They are small, soft-bodied insects typical of the order Psocodea.
Soa
Soa is a genus of booklice in the family Lepidopsocidae, order Psocodea. These small, wingless insects inhabit sheltered microhabitats and feed on organic debris. The genus was established by Enderlein in 1904 and is currently accepted in modern classifications.
Speleketor
Speleketor is a genus of large-winged psocids (booklice/barklice) in the family Prionoglarididae. The genus was established by Gurney in 1943 and contains at least three described species. Members are found in the southwestern United States. Psocids in this genus are characterized by relatively large wings compared to body size, distinguishing them from many related taxa.
Sphaeropsocus
Sphaeropsocus is a genus of small psocopterans in the family Sphaeropsocidae, first described by Hagen in 1882. It belongs to the suborder Troctomorpha, a group of barklice and booklice characterized by specialized mouthpart structures. The genus is part of a small family containing few described species, most of which are rarely encountered. Members of this genus are minute insects associated with dead plant material and organic debris.
Stenocaecilius
lizard barklice
Stenocaecilius is a genus of barklice in the family Caeciliusidae, commonly referred to as lizard barklice. The genus was established by Mockford in 2000 and contains more than 40 described species. Members of this genus belong to the order Psocodea, a group of small, often overlooked insects associated with dead plant material.
Stimulopalpus
tropical barklice
Stimulopalpus is a genus of tropical barklice in the family Amphientomidae, containing at least 30 described species. Members of this genus are small, wingless or weakly winged insects that inhabit tropical environments. They belong to the order Psocodea, which includes barklice, booklice, and parasitic lice. The genus was established by Enderlein in 1906 and represents one of the more species-rich genera within its family.
Tapinellinae
Tapinellinae is a subfamily of small, wingless insects within the family Pachytroctidae (order Psocodea). These minute hexapods are part of the diverse assemblage of barklice and booklice relatives, though specific biological details remain poorly documented. The subfamily was established by Enderlein in 1908 and contains genera characterized by particular morphological features of the head and mouthparts. Members are found in association with decaying organic matter in forest habitats.
Teliapsocus
shaggy psocids
Teliapsocus is a genus of shaggy psocids in the family Dasydemellidae, established by Chapman in 1930. The genus contains at least two described species: T. conterminus (1863) and T. distinctus (1986). These insects are small, winged barklice that inhabit vegetation and are part of the diverse Psocodea order.
Trichopsocus
lash-faced psocids
Trichopsocus is a genus of psocids (barklice and booklice) in the family Trichopsocidae, commonly referred to as lash-faced psocids. The genus contains nine described species distributed across multiple continents. Members are small, winged insects typically associated with vegetation and tree bark.
Trichopsocus dalii
Trichopsocus dalii is a small barklouse species in the family Trichopsocidae, characterized by its green coloration. It has been recorded across Europe, North Africa, the Middle East, and North America. The species is associated with a broad range of woody host plants.
Valenzuela
lizard barklice
Valenzuela is a large genus of barklice in the family Caeciliusidae, commonly known as lizard barklice. The genus contains at least 300 described species, making it one of the most diverse genera within Psocodea. Some species are known from Eocene fossils in Poland and Russia, indicating a long evolutionary history. Members of this genus are small, winged or wingless insects that inhabit bark and leaf litter environments.
Valenzuela lachloosae
Valenzuela lachloosae is a species of barklouse in the family Caeciliusidae, order Psocodea. It is an insect in the class Insecta, phylum Arthropoda. No specific ecological or biological details are documented for this species. The genus Valenzuela contains multiple described species, most of which are poorly known.
Xanthocaecilius
lizard barklice
Xanthocaecilius is a genus of lizard barklice established by Mockford in 1989. The genus contains at least two described species: Xanthocaecilius quillayute (Chapman, 1930) and Xanthocaecilius sommermanae (Mockford, 1955). These insects belong to the order Psocodea, a group that includes barklice, booklice, and parasitic lice. The genus has been recorded from Mexico and is part of the family Paracaeciliidae (sometimes referenced as Caeciliusidae in older literature).