Abstract: Taxonomical features including color and chaetotaxy of the head, thorax and abdomen of Hepialus oblifurcus larva are described. This larva is the main hOSt of the fungus Cordeceios sinensis; they form the insect-herb which has been used as materia medica for a long history in China. Head capsule is nearly circular and light yellow-brown or yellow-brown in color. Postoccipital su[cus is black These are six ocelli arranged in two rows on each side of the head. Clypeus is triangular and light yellow-brown in color. Clypeal membrane is long and narrow and milky white. Labrum is lobe-like and yellowbrown. Mandible is dark brown and there are five teeth at its end. Fusulus is long and thin On the head there are two pairs of vertical setae, three pairs anterior setae, two pairs posterior setae, a pair lateral setae, two pairs genal setae, three pairs ocellar setae, three pairs subocellar setae, two pairs frontal setae, three pairs clypeal setae and five pairs labral setae. The thorax and abdomen are milky white during the first and second instars.After the third instar, it is divided into two parts whose boundary is located at the middle of the first abdominal segment. The anterior part is light yellow-white and the posterior part is jade yellow. Prothoracic shield is large, half moon-shaped and light yellow. There are nine pairs of elliptical spiracles. Pleopod crotchets of the first instar larva are in form of uniserial circle and those of larva from second to eight instar are in form of multiserial circle. Crotchets of the anal foot are in form of multiserial penellipse. On the prothorax, there are two pairs of anterodorsal setae, two pairs dorsal setae, two pairs subdorsal setae three pairs lateral setae, two pairs subventral setae and a pair of ventral setae. There are no anterodorsal setae and only a pair of subventral setae on mesothorax and metathorax. Chaetotaxy of abdominal segments can be divided into three types which vary in the number of subvenral and ventral setae.

Key words: Hepialus oblifurcus Chu et Wang——taxonomical feature