Louse Morphology and Identification

1	Head broad; front usually rounded, sometimes triangular	[Biting Lice] 5
	Head long; front usually pointed	[Anoplura] 2
2	All legs of similar size; Paratergal plates on abdominal segments present and heavily chitinised; On ungulates	Haematopinus
	All legs of similar size, Paratergal plates on abdominal segments present and heavily chitinised; On humans	Pediculus
	1st pair of legs shorter than others	3
3	2 rows of ventral setae on each abdominal segment; Spiracles not on tubercles	4
	1  row of ventral setae on each abdominal segment, Spiracles on tubercles which protrude from the abdomen	Solenopotes
4	Paratergal plates absent; On cattle, sheep, goats and dogs	Linognathus
	Paratergal plates present; On rodents	Polyplax
5	Antennae 3 to 5 segmented, not hidden in antennal grooves	[Ischnocera] 6
	Antennae 4 segmented and hidden in antennal grooves	[Amblycera] 12
6	On Birds; Antennae 5 segmented; Paired claws	7
	On mammals; Antennae 3 segmented; Single claws	10
7	Hind legs similar length to first two pairs of legs	8
	Hind legs at least twice as long as first two pairs; Body long and narrow; On poultry	Lipeurus
8	3 long bristles project from each side of the dorsal surface of the head; Barrel-shaped body; ~2m long	Cuclotogaster
	2 long bristles projecting from each side of the dorsal surface of the head	9
9	Distinct hollow margin posterior to antennae; Marked angular corners at the posterior margins; 3-5mm long; On Poultry	Goniodes
	Head rounded; Less than 2mm long; On poultry	Goniocotes
10	Head triangular; On cats	Felicola
	Head rounded anteriorly	11
11	On ruminants or horses	Bovicola
	On dogs	Trichodectes
12	On birds	13
	On mammals	14
13	~2mm long; Abdomen with sparse covering of setae; Found on thigh or breast feathers	Menopan
	Larger lice (~3.5mm); Abdomen with dense covering of setae; Found on thigh, breast or perivent feathers	Menacanthus
14	On guinea pigs; Oval abdomen; 6 pairs of ventrolaterally located abdominal spiracles	Gyropus
	On Guinea pigs; Slender abdomen (sides parallel); 5 pairs of ventrally located abdominal spiracles	Gliricola
	On dogs	Heterodoxus