Haemocytes associated with basement membrane of sex pheromone gland of Trichoplusia ni (Lepidoptera: Noctuidae). Ultrastructural observations

Abstract

In female Trichoplusia ni, granular haemocytes are observed near the basement membrane of developing sex pheromone gland cells while plasmatocytes are observed near the basement membrane of unmodified epidermal cells. The basement membrane underlying gland cells is clearly different from that of other epidermal cells. There is a thin amorphous layer (layer 1) which is also present beneath unmodified cells, and a second layer (layer 2) apposing the haemocytes. Layer 2 is distinctly banded which results from tubules similar in dimensions and structural appearance to those observed within granules of the granular haemocytes. The observations indicate that the granules participate in the formation of layer 2 by emptying their contents into the haemocoel next to layer 1.