Green-veined white

Description

Pieris napi,vulgarly called white verdinervada,is a butterfly of medium-small size (males between 4,5 and 5,and females between 4 and 5 cm in span),of white front with black spots and reverse with greenish nerves,and with sexual dimorphism.It belongs to the family Pieridae,and was described by Linnaeus in 1758.The polymorphism of this species is very marked: there are differences between the butterflies of the first generation,more intensely colored,and those of the following generations.There are also notable differences between populations of different places and,even,between individuals of the same population.The front or upper face of the wings is white with black spots.The reverse is white and yellow lemon intense in the first generation,and pale in the others,with grayish spots and greenish veins.The obverse of the anterior wings of the males is white with the gray coast and a gray apical spot,sometimes interrupted by small black strokes.The basal area is gray in its proximal part and white in the distal zone,the disc,postdiscal and submarginal areas are also white with veins finely highlighted in gray.In the postdiscal area a blackish spot appears in E3.The hind wings are white with a black postdiscal spot on E7.The reverse wing is white,yellow and with greenish strokes.The previous ones have the yellowish apical zone and the veins softly labeled yellow,less in the first generation that are thickly marked with gray.In E3 a black dot appears.The posterior ones are pale yellow with a grayish spot on E7;in the first generation these wings are intense yellow with veins marked by thick greenish strokes,the greenish E7 stain being also.The wings of the females are similar,with spots of greater extension.The obverse of the previous ones has a darker basal area,with a black and elongated spot on E1a and three other black postdiscal spots on E1b,E3 and E5 that is confused with the apical spot.As in the rest of the species of their family,the imagos have a small head,with antennas in a club,and well-developed palps.The three pairs of legs are functional.Its forewings form an acute angle at its base,while the hindwings,which have a greater alar surface,are rounded.Two anal nerves are characteristic in the posterior wings.The caterpillars are yellowish-green,elongated,with a small head,cylindrical,and without spines.The chrysalises,are hung by the cremáster of the stems of the hospedadoras plants and they are fixed with a cíngulo of silk,acquiring the tonality of the plant in which they are.It can be confused with other species of the same genus such as P.brassicae,P.rapae,P.ergane or P.mannii.