ANISOPODIDAE

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 : 724

ANISOPODIDAE

Description ( Fig. 2F )

Testis: Each testis is pear-shaped, with short anterior filaments, covered by brownish fat tissue ( Abul-Nasr, 1950).

Epididymis: Not differentiated.

Vas deferens: These ducts are rather short, running posteriorly, clothed in brownish fat tissue, as found on the testis. The ducts consist of one thin layer throughout, except for a layer of glandular cells at the junction with the seminal vesicle ( Abul-Nasr, 1950).

Accessory gland and seminal vesicle: Each vas deferens empties separately into the proximal end of a pair of elongate accessory glands ( Abul-Nasr, 1950). These long glands remain separate and possess a layer of glandular cells that produce a secretion that surrounds the spermatozoan mass ( Abul-Nasr, 1950). Each gland is coated with a thin layer of circular muscles and large amounts of spermatozoa are stored in this paired gland shortly after emergence of the adult ( Abul-Nasr, 1950).

Ejaculatory duct: Each gland empties separately into the ejaculatory duct, which remains medially divided, entering the sperm pump closely appressed. This duct is long and convoluted, starting as a thickened tube, which gradually decreases in thickness posteriorly. Circular muscles coat the distal portion of the duct ( Abul-Nasr, 1950).

Ejaculatory apodeme, sperm pump, and aedeagus: The ejaculatory apodeme is rod-shaped, and acts as a piston to compress the sperm pump, forcing the seminal fluid into the long, slender, coiled aedeagal tube ( Abul-Nasr, 1950). The sperm pump is partially enclosed by the fused, concave, plate-like paramere.

Remarks: The male genital tract of Anisopodidae was illustrated by Abul-Nasr (1950) and Dahl (1980). The aedeagus is very long and thread-like and the sperm pump clearly functions to pump seminal fluid through this tube. The ejaculatory duct is a paired tube and no spermatophores are formed.

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.