Keys to Larvae of Veterinary Importance in Australia

1	Larvae with obvious spines or processes on each segment	2
	Larvae without obvious spines or processes (smooth)	7
2	Spines on ventral surface only; Mouth hooks well developed; Found in sheep nasal sinuses	Oestrus ovis
	Spines encircling body	3
3	Fleshy processes on dorsal and lateral aspects, few on ventral surface; Rows of small spines on first 2 or 3 anterior segments thereafter spines on central aspect; Larvae slender and pointed anteriorly	Chrysomya rufif
	No fleshy processes	4
4	Densly covered with small black spines which form bands at posterior margins of segments; Spiracles slit straight; Larvae slender (NOT IN AUSTRALIA)	Chrysomya bezziana
	1 or 2 rows of flat spines on the anterior margin of most segments; Larvae with 3 anterior triangular segments and remainder of larvae with parallel sides;	[Gasterophilus] 5
5	One row of spines on each segment	G nasalis
	Two rows of spines on each segment	6
6	Mouth hook with saddle-like depression	G intestinals
	Ventral side of segment 3 with 1 interrupted row of spines; Mouth hooks uniformly bent	G haemorrhoidalis
7	Larvae robust and rounded at both ends; Rudimentary mouth hooks; found in skin of cattle; Very small spines present (NOT IN AUSTRALIA)	Hypoderma sp
	Larvae slender; Pointed anteriorly and tapering to a large posterior part	8
8	Posterior spiracles sunken and often completely hidden in rounded cavity; Slit nearly vertical	Sarcophaga sp
	Posterior spiracles not sunken; Slit never vertical	9
9	Slit in posterior spiracle straight	[Calliphoridae] 10
	Slit sinuous	Musca sp
10	Peritreme broken	Chrysomya
	Peritreme entire	11
11	Peritreme thick; Accessory sclerite between mouthhooks (can't see in whole maggots)	Calliphora sp
	Peritreme thin; No accessory sclerite	Lucilia sp