Epipsocidae

Introduction

Epipsocidae includes over 140 species in 16 genera worldwide.  The family is mainly tropical with major radiations in South America, Africa, and Malaysia.  Two species are known from North America in the genus Bertkauia.

Epipsocids are medium to large-sized bark lice (~10 mm in length).  They live on bark, in foliage, in leaf litter, and on shaded rocks.

Characteristics

Synapomorphies

• Antennal scape is membranous over much of its ventral surface, and well sclerotized only at the base.
• Head lacks epistomal suture.
  
• Forewing has single anal vein because vein A2 is absent.
• Underside (ventral) surface of forewing is hairy.

General Characters

• Head:
  
• Antennae have 13 segments.
• Ocelli are sometimes grouped on a tubercle.
  
• Head is long due to long cheeks (genae).
• Legs: Tarsi have 2 segments.
• Wings:
• Underside (ventral) surface of forewing is hairy.
• Forewing veins and margins are hairy, hairs are arranged in single rows.
• Forewing veins:
• Areola postica is long and narrow, free of vein M.
  
• Pterostigma is long and narrow.
• Long crossvein connects veins Rs and M.
• Forewing has single anal vein because vein A2 is absent.
• Hindwing veins and margins are sometimes hairy.
• Male:
  
• Phallosome is usually open anteriorly, closed and sometimes pointed posteriorly.
• External parameres are broad and taper posteriorly.
• Female: 
  
• Subgenital plate is rounded and single-lobed.
• Gonapophyses are sometimes reduced and lacking ventral and/or dorsal valve:
• Dorsal valve (when present) is elongate and may be fused with external valve.
• Ventral valve (when present) is long and pointed.
• External valve is hairy.
• Eggs: Eggs are smooth, laid singly, and are covered with debris.

How to Know the Family

• Head is long due to long cheeks (genae).
• Ocelli are sometimes grouped on a tubercle.
• Forewing has single anal vein because vein A2 is absent.
  
• Underside (ventral) surface of forewing is hairy.

Family Monophyly

The monophyly of Epipsocidae is strongly supported by a morphological phylogeny of 11 Epipscocid genera (Casasola Gonzalez & Garcia Aldrete 2002) and by a molecular analysis that included 18S rDNA sequences of three species (Goja sp., Epipsocus sp., and Bertkauia crosbyana) (Johnson et al. 2004).

References

Casasola Gonzalez, J. A. C. & A. N. Garcia Aldrete. 2002. A taxonomic revision of genus Goja (Psocoptera: Epipsocidae). Mexico City: UNAM Press.

Johnson, K. P. & E. L. Mockford. 2003. Molecular Systematics of Psocomorpha (Psocoptera). Systematic Entomology 28: 409-40.

Johnson, K. P., K. Yoshizawa, and V. S. Smith. 2004. Multiple origins of parasitism in lice. Proceedings of the Royal Society of London B 271:1771-1776.

Lienhard, C. and C. N Smithers. 2002. Psocoptera (Insecta) World Catalogue and Bibliography. Muséum d'Histoire Naturelle, Geneva, Switzerland.

Mockford, E. L. 1998. Generic definitions and species assignments in he Family Epipsocidae (Psocoptera). Insecta Mundi 12: 81-91.

Mockford, E. L. 1993. North American Psocoptera (Insecta). Sandhill Crane Press, Gainesville, Florida.

Smithers, C. N. 1996. Psocoptera. Pp. 1-80, 363-372 (Index) in Wells A. (ed.) Zoological Catalogue of Australia. Vol. 26. Psocoptera, Phthiraptera, Thysanoptera. Melbourne: CSIRO Publishing, Australia.

Yoshizawa, K. 2002. Phylogeny and higher classification of suborder Psocomorpha (Insecta: Psocodea:'Psocoptera'). Zoological Journal of the Linnean Society 136: 371-400.