I hope these are no reposts..
The head of a maggot or the larva of a bluebottle fly
A cat flea (Ctenocephalides felis) amongst cat hairs
A common housefly (Musca domestica)
A house dust mite (Dermatophagoides pteronyssinus)
A meal (or flour) mite (Acarus siro)
The head of a Silverfish (Lepisma saccharina)
The head of a red flour beetle (Tribolium castaneum)
A daddy-long-legs spider (Pholcus phalangioides)
The head of a human flea (Pulex irritans) (Looks like the girl from that Avatar movie I never saw)
The head of a yellow dung fly (Scatophaga stercoraria)
The head of a Jumping Spider (family Salticidae)
A fly
The head of a tropical caterpillar (order Lepidoptera)
The head of a froghopper (superfamily Cercopoidea)
A dog flea (Ctenocephalides canis)
A common wasp (Vespula vulgaris) head
A wasp's head (order Hymenoptera)
The head of a soldier turtle ant (Cephalotes sp.) from the Amazonian rainforest
The head of a honey bee (Apis sp.)
The head of a bedbug (Cimex sp.)