What length and time characterize the 1st instar maggot stage?

• A. 5 mm long after 1.8 days
• B. 10 mm long after 2.5 days
• C. 14-16 mm long after 4-5 days
• D. 2 mm long after 0.5 days

Answer: (A)

In forensic entomology, the timing of larval growth is tied to the size of the maggots as they develop through instars. The first instar is the freshly hatched larva, which grows quickly as it feeds. Under typical conditions, it reaches about 5 millimeters in length by roughly 1.5 to 2 days after hatching, marking the end of the first instar and the start of the second. So describing a maggot as about 5 mm long at around 1.8 days fits this growth pattern for the 1st instar.

The other descriptions point to later stages or earlier moments: about 10 mm after 2.5 days would be a larger, later instar; 14–16 mm after 4–5 days indicates a much later stage; and 2 mm after 0.5 days is earlier and doesn’t reflect the typical size reached by the end of the first instar.