PSYCHODIDAE

Sinclair, Bradley J., Borkent, Art & Wood, D. Monty, 2007, The male genital tract and aedeagal components of the Diptera with a discussion of their phylogenetic significance, Zoological Journal of the Linnean Society 150 (4), pp. 711-742 : 722-724

PSYCHODIDAE

Description ( Fig. 2E )

Testis: The testes are oblong–oval or rounded, with tapered anterior ends. Spermatozoa are densely packed in the posterior chambers.

Epididymis: Not differentiated.

Vas deferens: A short, narrow duct enters the accessory gland separately in Phlebotomus Rondani & Berté ( Davis, 1967; Perfil’ev, 1968; Just, 1973). In contrast, in other psychodids the entire reproductive tract is modified and the vasa deferentia are broad tubes little differentiated from the accessory glands ( Friele, 1930; Matsuda, 1976).

Accessory gland and seminal vesicle: Only a single heart-shaped gland is present in Phlebotomus and is here referred to as the accessory gland, but its bilobed condition suggests fusion of paired glands. No seminal vesicle in Phlebotomus is present. The vasa deferentia enter each side of this gland and are enveloped, forming a pair of small inner chambers with broad gland cells and a narrow exit to the single large inner chamber of this gland ( Just, 1973: fig. 7, Vsem; Jobling & Lewis, 1987). The cells within this larger chamber also have a secretory function. No seminal vesicle is identified in the modified genital tract of Tinearia alternata (Say) and Satchelliella pulustris (Meigen) , although two pairs of accessory glands are present ( Friele, 1930; Just, 1973).

Ejaculatory duct: A single narrow, tapered duct exits the accessory gland in Phlebotomus and enters the sperm pump ( Just, 1973). The ejaculatory duct in Satchelliella Vaillant is broad and muscular, directly associated with the base of the aedeagus and lies immediately ventral to a long ejaculatory apodeme, which is articulated with the aedeagus. The inner lumen of the duct consists of finely folded epithelium, which aids in the flexibility and contraction of the duct.

Ejaculatory apodeme, sperm pump, and aedeagus: The single ejaculatory duct enters the sperm pump anteriorly. This pump bears a rod-like ejaculatory apodeme that compresses the chamber in a piston-like manner, ejecting the seminal fluid through long, thread-like paired ducts to the phallotrema in Phlebotomus ( Perfil’ev, 1968; Just, 1973). The sperm pump is quite different in Satchelliella and sperm is probably forced out through the apex of the aedeagus by the combined action of the ejaculatory apodeme moving backwards and forwards and the muscular contractions of the ejaculatory duct.

Remarks: The narrow opening of the aedeagus and the presence of a sperm pump indicate that spermatophores are probably not produced in these genera of Psychodidae .

Figures

Figure 2. Male internal reproductive organs (dorsal view). A, Tipula oleracea L. (Tipulidae) [modified from Keuchenius (1913)]. B, Philorus vividis Kitakami (Blephariceridae) (accessory glands not observed) (scale bar = 0.1 mm). C, Lucilia sp. (Calliphoridae) [modified from Hori (1960)]. D, Trichocera annulata Meigen (Trichoceridae) [modified from Neumann (1958)]. E, Phlebotomus sp. (Psychodidae) [modified from Just (1973) and Perfil’ev (1968)]. F, Sylvicola sp. Anisopodidae [modified from Abul-Nasr (1950) and Dahl (1980)]. acc gl, accessory gland; aed, aedeagus; ej dt, ejaculatory duct; sem ves, seminal vesicle; spm pmp, sperm pump; tes, testis; vas df, vas deferens.