An unidentified gland-like tissue near the androgenic gland of red swamp crayfish, Procambarus clarkii

ABSTRACT:   Among all of the decapods that have been studied, only one kind of gland, the androgenic gland, has been found attached to the subterminal ejaculatory region of the vas deferens. In the present study of the red swamp crayfish, it was found that two kinds of gland-like tissues were attached to the subterminal ejaculatory region of the vas deferens. One of the tissues, which is referred to as TIB, is located inside the body cavity, whereas the other tissue, which is referred to as TIC, is inside the coxa. The characteristics of TIB resemble those of the androgenic gland of other malacostracans. The TIC cells, however, are smaller and more basophilic due to the small size and high density of their cytoplasm and nuclei. Moreover, black fibers, similar to the nerve fibers of the ganglion, were detected among the TIC cells after Bodian's stain. The conclusion is that TIC may be a newly found male sexual characteristic and further research is needed to confirm its functions.