Order Anoplura
Sucking Lice
General Description
Anoplura are described as wingless (apterous), hemimetabolous (having a simple metamorphosis i.e. no pupa) ectoparsites (living on the outside of their hosts) of mammals.
Morphological Characteristics
 | The mouthparts are adapted for sucking and retractable into a special cavity in the head when not being used with mandibulate mouthparts |
| The range in size from 0.5 to 10 mm long dorsoventrally flattened |
| Antennae short; 3-5 segmented |
| No ocelli and no cerci |
| Reduced or absent compound eyes |
| Strengthened legs which have large single claws and only a single tarsal segment as part of their special adaptation to clinging on. |
Biology
| Feed on fresh blood and only occur on mammals |
| The eggs are oval and whitish when first laid and are glued by the female louse onto the hair or skin of the host. |
| A female will lay about 300 eggs, approximately 10 eggs a day. |
| The eggs take 8 to 12 days to hatch depending on the species. |
| There are three larval instars which take 12 to 19 days to become adult. |
| There is then a further period of 1 to 3 days before the new adults become sexually mature. |
Distribution
There are about 300 described species worldwide
Economic Importance
Sucking lice are responsible for the spread of disease in humans and domestic animals. Pediculosis is an infestation of lice anywhere on the human body. It is usually characterized by skin irritation, allergic reactions, and a general feeling of malaise. In addition, the human body louse is responsible for the spread of relapsing fever (Borellia recurrentis), epidemic typhus (Rickettsia prowazeki), and trench fever (Rickettsia quintana). Lice associated with domestic animals have also been implicated in the transmission of disease (e.g., hog lice spread pox virus and cattle lice spread rickettsial anaplasmosis).
Interesting Facts
| During the war, louse-borne disease were common when soldiers were forced to live in crowded and unsanitary conditions. Trench fever was especially widespread during World War I, and was probably a major factor in the final collapse of the Russian army. |
| Some South American Indian tribes members believe it is customary to collect and eat the lice from one another's body. They view this behavior as a way of sharing each other's soul. |
Lice Pictures
From Iowa State University Entomology Image Gallery.Louse Taxonomy and Phylogeny From Glasgow University