Fig. 2

Elongation of the body at successive developmental stages in Thamnocephalus. a Body length plotted against developmental stage. The animals roughly double in length as the body segments are specified. b Percent change in body length plotted against developmental stage, demonstrating the impact of the first molt on change in body length. c Overall ventral area of the trunk increases at each stage (after four En stripes added). Black bars represent the thoracic segments added prior to the first molt (dashed line), subsequent thoracic segments are gray. Genital segments (modified abdominal segments 1 and 2) are marked by solid lines and followed by additional abdominal segments. Box and whisker representation of these data in Additional file 3. On average, 23 larvae per stage were scored for a total of 433 larvae, exact distribution of larvae in each hour and developmental stage included in Additional file 15