Sternorrhyncha

Sternorrhyncha
An aphid.
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hemiptera
Suborder:	Sternorrhyncha
Superfamilies
Aleyrodoidea Aphidoidea Coccoidea Phylloxeroidea Psylloidea

The Sternorrhyncha suborder of the Hemiptera contains the aphids, whiteflies, and scale insects, groups which were traditionally included in the now-obsolete order "Homoptera". "Sternorrhyncha" refers to the rearward position of the mouthparts relative to the head.

Distributed worldwide, all members of this group are plant-feeders (phytophagous), and many are major crop and ornamental pests.

Many exhibit modified morphology and/or life cycles, including phenomena such as flightless morphs, parthenogenesis, sexual dimorphism, and eusociality.

Phylogeny

The phylogeny of the Sternorrhyncha, inferred from analysis of small subunit (18S) ribosomal RNA, is shown in the cladogram.

Sternorrhyncha	Psylloidea (jumping plant lice, etc.)       Aleyrodoidea (whiteflies)       Coccoidea (scale insects)   Aphidomorpha   Phylloxeroidea (phylloxera bugs)     Aphididae (aphids)

Groups

Well-known groups in the Sternorrhyncha include:

• aphids – (Aphididae)
• woolly and gall-making aphids (Eriosomatinae)
• pine and spruce aphids (Adelgidae)
• phylloxerans (Phylloxeridae, including the vine phylloxera)
• whiteflies – (Aleyrodidae)
• jumping plant lice (Psyllidae and allied families)
• Superfamily Coccoidea (scale insects)
  • cottony cushion scales, giant coccids, and ground pearls (Margarodidae)
  • armoured scales (Diaspididae)
  • cochineal insects (Dactylopiidae)
  • lac scales (Kerriidae, Lacciferidae, Tachardinidae)
  • soft scales (Coccidae)
  • pit scales (Asterolecaniidae)
  • mealybugs (Pseudococcidae)
  • felted scales (Eriococcidae)

External links

• Suborder Sternorrhyncha—Plant-parasitic Hemipterans at BugGuide