Pioneer white butterfly, Belenois aurota (Lepidoptera: Pieridae) a new threat to ker (Capparis decidua) plant in arid region of India: incidence and morphological evidence

The pioneer white butterfly, Belenois aurota Fabricius, 1793 (Lepidoptera: Pieridae), has recently emerged as a major pest of ker (Capparis decidua) plant in arid region of India and causes around >70% damage to wild and cultivated ker plants. The maximum incidence (86.67%) was observed in first fortnight of December and the minimum (11.67%) in first fortnight of September. The average numbers of insects ranged between 1.33 and 10.33 larvae per branch of plant and the lowest in second fortnight of March and the highest in first fortnight of December. Adults of this small butterfly were blacks and whites in color with black markings on both upper and under sides broader, the white spots on black apical area of fore wing often sub-obsolete above. Eggs were laid in batches on young shoots or new branches and were 1.74 mm in length, 1.55 mm in width, and yellow in color when first laid. The length and width of 1^st instar larvae were 2.05 mm and 0.47 mm, respectively and feed on branches gregariously. The lengths of 2nd, 3rd, and 4^th instar larvae were 5.12 mm, 12.27 mm, and 18.6 mm, respectively. The 5^th instar larvae were 24.71 mm long and 3.93 mm wide and long, cylindrical, broader towards the head, slightly tomentose on back, hairy on the sides. Pupae were 18.84 mm long and 4.92 mm wide and transparent, pale cream-colour. Adult females had a body length of 13.23 mm and a wingspan of 41.65 mm. Bodies of males were 11.54 mm long and their wingspan measured 38.72 mm. The lengths of male and female antennae were 11.40 mm and 10.54 mm, respectively