Order Acari

• Phylum: Arthropoda

  Subphylum: Chelicerata

  Class: Arachnida

  Order: Acari

  Family: Tydeidae

  Genus: Lorryia

  Species: Lorryia formosa

  Common name: citrus yellow mite

  A) 4 pairs of legs

  B) setae

  C) Chelicerae

  D) capitulum

  E) idiosoma

  
• Phylum: Arthropoda

  Subphylum: Chelicerata

  Class: Arachnida

  Order: Acari

  Family: Ixodidae

  Genus: Dermacentor

  Common name: tick

  A) 4 pairs of legs

  B) sculum

  C) opisthosoma

  D) podosoma

  E) capitulum

  F) Chelicerae

  
• Lack of body division: abdomen fused with prosoma
• Capitulum or gnathosoma: head region carrying the mouth parts
• Rostrum or tectum formed as the dorsal body wall projects
• The chelicerae and pedipalps are variable in structure depending on function
• Chelicerae may become needle-like or terminate in pincers
• 4 pairs of legs are each 6 segmented: composed of a coxa, a trochanter, a femur, a genu, a tibia, and a tarsus (the last with a pair of claws)
• Ventral side covered by plates
• Genital plate bears genital orifice
• Hairs or setae cover the mite bud