Lucilia Illustris - Larvae

Larvae

The larvae develop in three stages, or instars. In the first instar, it is difficult to determine the dispersion of the spines due to some segments not being pigmented. The second through ninth segments each have a full set of spines as anterior borders. However, the color starts to change in the eighth and ninth segments: segment 8 has lighter colored spines and the ninth segment's spines are practically void of color. The spines are reduced to one or two rows in segment 9, but segment 10 has several rows that are lightly colored. Segment 11 is characterized by two or three rows of dark spines as a posterior border on the dorsal side. Segment 12 is characterized by tubercles, with an inner set on the upper border. Cephalopharyngeal sclerite are darkly pigmented.

In the second instar, segments 2 through 9 are characterized by a complete band of spines as a front border (as in the first instar). Segment 8 has spines, but they are only located ventrally and laterally. Segments 9 through 12 have complete bands of spines as a posterior border, but segment 9 only has one or two irregular rows of spines. The tubercles found on the upper border of the last segment are have a broad curve and are similar in size to the third instar tubercles. The cephaloskeleton has a dorsal cornua of consistent width until it comes to a point at the posterior end. Six to eight branches are found on the frontal spiracles.

The third instar has bands of spines completely around the spine at segments 2 through 9. Segment 10 has a band of spines, but there is generally a small area on the front that is not complete. There are five or six irregular rows on the back of segment 11. Segment 12 is usually smooth on its dorsal surface. The posterior spiracles are relatively large and darkly pigmented; the anterior spiracles (generally six to eight) have relatively large branches. The cephaloskeleton is also large and darkly colored.