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Polyplacidae
Polyplacidae is a family of lice in the suborder Anoplura, the sucking lice. Lice in this family are known commonly as the spiny rat lice. The family has a cosmopolitan distribution. As of 2010 there were 193 species.Light, J. E., et al. (2010)Evolutionary history of mammalian sucking lice (Phthiraptera: Anoplura).''BMC Evolutionary Biology'', 10(1), 292. These are small to medium-sized lice. They are usually sexually dimorphic. They have 5-segmented antennae and small, slender, clawed forelegs. Their middle and hindlegs may be almost equal in size, or the hindlegs may be larger.Durden, L. A. & Webb, J. P. (1999)''Abrocomaphthirus hoplai'', a new genus and species of sucking louse from Chile and its relevance to zoogeography. ''Medical and Veterinary Entomology'', 13(4), 447-452. Lice in this family are parasites of many types of small mammals, including spiny rats, cavies, rabbits, hares, chinchillas, bushbabies, lemurs, squirrels, shrews, pouched rats, treeshrews, hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sucking Louse
Sucking lice (Anoplura, formerly known as Siphunculata) have around 500 species and represent the smaller of the two traditional superfamilies of lice. As opposed to the paraphyletic chewing lice, which are now divided among three suborders, the sucking lice are monophyletic. The Anoplura are all blood-feeding ectoparasites of mammals. They only occur on about 20% of all placentalian mammal species, and are unknown from several orders of mammals ( Monotremata, Edentata, Pholidota, Chiroptera, Cetacea, Sirenia, and Proboscidea).Piotrowski, F. (1992): Anoplura (echte Läuse). de Gruiter; 61 pp. (page 8) They can cause localized skin irritations and are vectors of several blood-borne diseases. Children appear particularly susceptible to attracting lice, possibly due to their fine hair. At least three species or subspecies of Anoplura are parasites of humans; the human condition of being infested with sucking lice is called pediculosis. ''Pediculus humanus'' is divided into two sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrew
Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to different families or orders. Although its external appearance is generally that of a long-nosed mouse, a shrew is not a rodent, as mice are. It is, in fact, a much closer relative of hedgehogs and moles; shrews are related to rodents only in that both belong to the Boreoeutheria magnorder. Shrews have sharp, spike-like teeth, whereas rodents have gnawing front incisor teeth. Shrews are distributed almost worldwide; among the major tropical and temperate land masses, only New Guinea, Australia, and New Zealand have no native shrews; in South America shrews appeared only relatively recently, as a result of the Great American Interchange, and are present only in the northern Andes. The shrew family has 385 known species, making it the fourth- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyly
In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic group (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of synapomorphies and symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term was coined by Willi Hennig to apply to well-known taxa like Reptilia ( reptiles) which, as commonly named and traditionally defined, is paraphyletic with respect to mammals and birds. Reptilia contains the last common ancestor of reptiles and all descendants of that ancestor, including all extant reptiles as well as the extinct synapsids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
