Description of the mature larva of Ancistrocerus sikhimensis (Hymenoptera: Eumenidae)

The mature larva of A. sikhimensis is described, illustrated, and compared with that of other species of the genus so far described. The final-instar of this species and the different species recently described, or redescribed, in this genus are A. kitcheneri, A. longispinosus, and A. trifasciatus, and all can be differentiated on the basis of the following characters: (a) the development of antennae; (b) the development of the atrium with respect to the subatrium; (c) the number of the sensilla of the labrum and galea, and (d) the presence/absence of spinules and papillae on the labium.