Lucilia illustris

Lucilia illustris is a member of the Calliphoridae family of flies commonly known as a blow fly. Along with several other species, L. illustris is commonly referred to as the green bottle fly. L. illustris is typically 6–9 mm in length and has a metallic blue-green thorax. The larvae develop in three instars, each with unique developmental properties. The adult fly typically will feed on flowers, but the females need some sort of carrion protein in order to breed and lay eggs. Due to the predictable nature of development, Lucilia illustris is often used by forensic entomologists to determine time and place of death. Medically, L. illustris is often used for Maggot Debridement Therapy because it only causes myiasis in necrotic tissue. Lucilia illustris was first described by the German entomologist Johann Wilhelm Meigen in 1826. Its specific epithet is derived from the Latin illustris 'brilliant'. Lucilia illustris is 6–9 mm in length. Its bucca (cheeks) are colored black with slightly gray pollinose and black hairs. The first segment of the antenna is black; the second generally orange-tipped, and the third segment is about three times the length of the second segment and colored a dark brown or black. The arista (a bristle on the antenna) is dark brown or black, and has cilia that are dark and long. The back of its head is black and there are three to four rows of black cilia behind the eyes. A metallic blue-green thorax reflects bronze and purple. In some lights, silvery pollen appears on its back, as well as a dark line that extends along the back. Black setae can be found on both the propleuron and the hypopleuron, with brown setae on the prosternum. There are dark brown or black sclerites located at the wing-base, as well as dark brown or black found on the spiracle. L. illustris has black legs, translucent wings, and does not have a costal spine. The abdomen has similar coloring to the thorax, but looks slightly white in certain lights. The first segment of the abdomen has metallic and dark brown coloring. The second segment has a slight indication of a spot in the middle of the back on the front margin, as well as a row of hardly apparent bristles along the margin. The third and fourth segments both have long upright bristles, but the fourth segment's hairs are scattered and also includes a marginal row of bristles. 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 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.