Morphology and chemistry of the mandibular gland complex in the primitive termite, Zootermopsis angusticollis (Hagen) (Isoptera : Hodotermitidae)

Abstract

A pair of cephalic exocrine glands are described in the primitive termite Zootermopsis angusticollis (Hagen) (Isoptera : Hodotermitidae). One of the glands, the accessory mandibular gland, is apparently undescribed and is located ventrally near the mandibular gland. The 2 glands are located on either side of the head and open in a region of intersegmental cuticle between the maxilla and the lateral margins of the head capsule. Together, the 2 glands are termed the mandibular gland complex. The morphology of the 2 glands is described using light microscopy and scanning electron microscopy. The accessory mandibular gland is formed as an invagination of intersegmental cuticle, has the shape of a 3-fingered glove, and empties via a single large pore. The mandibular gland empties via numerous pores into a pore plate which, when folded, becomes a “pocket” or reservoir. Individual accessory mandibular glands were dissected free of intersegmental cuticle and the 2 major components of the secretion of the gland were identified as n-heneicosane and n-tricosane. It is suggested that the secretion of the accessory mandibular gland may function as a recognition pheromone and/or as a spreading agent for the secretion of the mandibular gland.