The Reproductive System of Some Florida Mosquitoes. I. The Male Reproductive Tract1

Abstract

A comparative system of the anatomical arrangement was made on 10 species, namely, Aedes triseriatus, A. taeniorhynchus, A. fulvus pallens, A. infirmatus, Psorophora howardii. Culex pipiens quinquefasciatus, Deinocerites cancer, Uranotaenia lowii, Culiseta inornata , and Anopheles crucians . The chief differences found were in the shape of the accessory glands, the time of formation of mature spermatozoa, and particularly in the arrangement of the seminal vesicles. The accessory glands were oval, or elongate, or pear-shaped; in U. lowii and A. taeniorhynchus they were shaped differently in newly emerged males than in older ones. In the Psorophora , the Culex , and the four Aedes species the seminal vesicles were conjoined or fused throughout their length, but in C. inornata, D. cancer, C. lowii , and A. crucians they were separate, connected only at the posterior ends. In the species with conjoined or fused vesicles the transfer of spermatozoa was rapid (10 to 15 seconds) during mating, but this was prolonged to 45 minutes or more in three of the four species with separate vesicles; mating behavior was not observed in Anopheles crucians , which is strikingly different from all the other nine species in the size and musculature of its ejaculatory duct. Active spermatozoa were found in the seminal vesicles within 15 minutes after emergence in P. howardii, D. cancer , and U. lowii ; after 6 hours in A. taeniorhynchus, A. triseriatus, A. infirmatus, C. p. quinquefasciatus, C. inornata , and A. crucians ; and after 20 hours in A. fulvus pallens.