Manual for Diagnosis of Screw-worm Fly - xcs consulting

A Manual for the Diagnosis of Screw-Worm Fly
6.2 Larvae
Because the first two larval instars are relatively inconspicuous and occupy only two days
of the 4-7 day larval development period, they are very rarely presented for diagnosis, and
so the larval separation key is confined to the third (final) instar larva (Fig. 16). Reference
to figures in key refers to scanning electron microscope photographs of mature larvae (Figs
18-28).
For further details of some of the larvae described in this key and other closely related species,
see Erzinçlioglu (1987), Fuller (1932), Kitching (1976) and Liu and Greenberg (1989).
1. Body with prominent projections of papillae on each segment (= ‘hairy maggot’) (A)
………………...............................................................................................................…2
- Body without prominent papillae except few on posterior segment (’smooth maggot’)
(B) ………………..................................................................................................………4
2. Very ‘hairy’ maggot, large larva (up to 17mm long); papillae present on both dorsal
and ventral surfaces …………………..................................................…………………..3
- Less ‘hairy’ maggot, small larva (