The male genital tract and aedeagal components of the Diptera with a discussion of their phylogenetic significance Sinclair, Bradley J. Borkent, Art Wood, D. Monty Zoological Journal of the Linnean Society 2007 2007-08-31 150 4 711 742 78Z 174624 [365,576,538,562] Insecta Blephariceridae Animalia Diptera 11 722 Arthropoda family   Description ( Fig. 2B)  Testis:Each testis is oval and pale (  PhilorusKellogg) or club-shaped, bent and twisted, and darkly pigmented ( Zwick, 1977).  Epididymis:Not differentiated.  Vas deferens:These ducts are long and slender and extend directly to the sperm pump (  Philorus) or are non-existent when the testis is rather elongate and empties directly into the sperm pump ( Zwick, 1977).  Accessory gland and seminal vesicle:There are one to two pairs of pale glands, which empty separately at the base of the elongate testes ( Zwick, 1977). The contents and function of these glands are unknown. No glands were observed in  Philorus.  Ejaculatory duct:The ducts exiting the testis remain completely separate for their entire length and empty separately and directly into the sperm pump ( Zwick, 1977; Sinclair, 2000: fig. 1). There appears to be no distinction between the vas deferens and the ejaculatory duct.  Ejaculatory apodeme, sperm pump, and aedeagus:The base of the aedeagus bears an enlarged ejaculatory apodeme, which compresses the sperm pump ( Sinclair, 2000). The aedeagus in Blephariceridaeis divided posteriorly into three narrow forks, with each narrow tube opening independently ( Fig. 2B).  Remark:The male genital tract of this family was studied by Zwick (1977).