Insects in the subfamily Phymatidae are commonly called ambush bugs after their habit of lying in wait for prey relying on their superb camouflage

Camouflage

Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...

. Armed with raptorial

Raptorial

The term raptorial implies much the same as "predatory", but most often refers to modifications of an arthropod's foreleg that make it function for the grasping of prey while it is consumed, where the gripping surfaces are formed from the opposing faces of two successive leg segments...

 forelegs, ambush bugs routinely capture prey ten or more times their own size. They form a subgroup within the assassin bugs.

Description

Phymatidae are 5–12 mm (0.196850393700787–0.47244094488189 ) long. In Phymata, the scutellum is triangular and shorter than the pronotum. In Macrocephalus the scutellum is narrow and rounded and extends to the tip of the abdomen

Abdomen

In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...

.

Phymatidae normally have a large fore femur

Arthropod leg

The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...

 and clubbed antennae

Antenna (biology)

Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....

. The forewing membrane

Biological membrane

A biological membrane or biomembrane is an enclosing or separatingmembrane that acts as a selective barrier, within or around a cell. It consists of a lipid bilayer with embedded proteins that may constitute close to 50% of membrane content...

s sometime lack distinct cell

Cell (biology)

The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....

s.

The antennae have four segments. There are two ocelli. The beak

Beak

The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...

 has three segments. The tarsi

Arthropod leg

The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...

 also have three segments. The rear half of the abdomen

Abdomen

In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...

 expands beyond the edges of the wings.

Taxonomy

Phymatidae was often given family-level status and this classification is still used in some textbooks. Based on cladistic analyses, however, ambush bugs (Phymatidae) are part of the family Reduviidae

Reduviidae

Reduviidae is a large, cosmopolitan family of predatory insects in the suborder Heteroptera...

 (assassin bugs).

Etymology

Phymatinae is derived from the Greek phymata meaning swollen which presumably refers to the enlarged abdomen and femora.

Taxonomy

Phymatinae contains the following species:

• Lophoscutus Kormilev, 1951
  • Lophoscutus affinis Guérin-Méneville, 1838
  • Lophoscutus prehensilis Fabricius, 1803
• Macrocephalus Swederus, 1787
  • Macrocephalus arizonicus Cockerell, 1900
  • Macrocephalus barberi Evans, 1931
  • Macrocephalus cimicoides Swederus, 1787
  • Macrocephalus dorannae Evans, 1931
  • Macrocephalus gracilis Handlirsch, 1897
  • Macrocephalus manicatus Fabricius, 1803
  • Macrocephalus notatus Westwood, 1841
  • Macrocephalus similis Kormilev, 1972
  • Macrocephalus uhleri Handlirsch, 1898
• Phymata Latreille, 1802
  • Phymata albopicta Handlirsch, 1897
  • Phymata americana Melin, 1930
  • Phymata arctostaphylae Van Duzee, 1914
  • Phymata borica Evans, 1931
  • Phymata crassipes
    Phymata crassipes
    Phymata crassipes is a species of assassin and thread-legged bugs belonging to the family Reduviidae, subfamily Phymatinae.Size 7-9 mm long. Their triangular scutellum is shorter than a pronotum without prominent tubercles. They have clubbed antennae and enlarged fore femora and abdomen, which...
    
    Fabricius, 1775
  • Phymata fasciata Gray, 1832
  • Phymata granulosa Handlirsch, 1897
  • Phymata luteomarginata Kormilev, 1957
  • Phymata luxa Evans, 1931
  • Phymata maculata Kormilev, 1957
  • Phymata noualhieri Handlirsch, 1897
  • Phymata pacifica Evans, 1931
  • Phymata pallida Kormilev, 1957
  • Phymata pennsylvanica Handlirsch, 1897
  • Phymata rossi Evans, 1931
  • Phymata saileri Kormilev, 1957
  • Phymata salicis Cockerell, 1900
  • Phymata vicina Handlirsch, 1897