The male genital tract and aedeagal components of the Diptera with a discussion of their phylogenetic significance

Abstract

The male genital tract of Diptera is surveyed, based on whole dissections, with emphasis on nematocerous infraorders and especially the Culicomorpha. The genital tracts of all available nematocerous families are described and illustrated, including, for the first time, those of the families Thaumaleidae, Dixidae, Hesperinidae, and Pachyneuridae, and, as an outgroup, the mecopteran family Nannochoristidae (Mecoptera). On the basis of outgroup comparison, the Diptera + Mecoptera + Siphonaptera share the synapomorphies of accessory gland continuous with the vas deferens and U-shaped vasa deferentia. Further synapomorphies of the male genital tract provide evidence of the monophyly of the Mecoptera + Siphonaptera, Boreidae + Siphonaptera, and the Blephariceridae + Psychodidae + Trichoceridae + Anisopodidae + Brachycera. The Bibionomorpha, Culicomorpha, and Ptychopteromorpha share the synapomorphy of paired, two-to three-chambered accessory gland complexes, with secondary losses in Corethrellidae + Culicidae. It is concluded that there is no convincing evidence for the monophyly of the Chironomoidea. A sperm pump with an ejaculatory apodeme and the absence of a spermatophore are considered to be part of the ground plan of Diptera, but, because of uncertainty as to the identity of the basal lineage within Diptera and the homology of the sperm pump outside of Diptera, the polarity of these features cannot be presently interpreted.

Ribosomal protein genes of holometabolan insects reject the Halteria, instead revealing a close affinity of Strepsiptera with Coleoptera

“…Other characters proposed to support the close affinities of these two orders (e.g. Wheeler et al, 2001;Whiting et al, 1997) have since been critically reinterpreted (Beutel and Pohl, 2006;Hünefeld and Beutel, 2005;Krenn, 2007;Kristensen, 1999;Sinclair et al, 2007). Studies using 28S rRNA data conflicted with results from 18S rRNA alone, as they did not recover the Halteria, and even placed Strepsiptera outside Holometabola altogether (Huelsenbeck, 2001;Hwang et al, 1998).…”

Structure and ultrastructure of spermatozoa of Chrysomya megacephala (Diptera: Calliphoridae)

“…The male internal reproductive organs in Chrysomya megacephala (Calliphoridae) comprise: testes, vas deferens, accessory glands, seminal vesicle, ejaculatory duct and resemble the pattern structure observed in other Diptera ( Joly et al, 2003 andSinclair et al, 2007). Such reproductive organs in Diptera are poorly known, with few detailed comparative studies ( Sinclair et al, 2007).…”

“…Such reproductive organs in Diptera are poorly known, with few detailed comparative studies ( Sinclair et al, 2007).…”

The State of Phylogenetic Analysis: Narrow Visions and Simple Answers—Examples from the Diptera (flies)

“…Features of adults, pupae and larvae become congruent at certain nodes when apomorphic and plesiomorphic features are distinguished. Subsequent morphologically-based work largely supported Hennig's conclusions, although there was significant further resolution and obviously plenty of questions remaining for further study (e.g., Borkent, 2012;Buck, 2006;Courtney, 1990Courtney, , 1991Courtney, , 1994aCumming et al, 1995;McAlpine, 1989;Michelsen, 1996;Oosterbroek & Courtney, 1995;Pape, 1992;Sinclair, 1992;Sinclair & Cumming, 2006;Sinclair et al, 1994Sinclair et al, , 2007Starý, 2008;Wood & Borkent, 1989;Woodley, 1989;Yeates, 2002). Wiegmann et al (2011) and Lambkin et al (2013) recently published partially complementary results of a sixyear (2004)(2005)(2006)(2007)(2008)(2009) cooperative effort between 17 different laboratories studying Diptera phylogeny and supported by an NSF grant of $2.4 million (US).…”

“…The character state distribution of this feature by Lambkin et al (2013) shows that it is absent in non-Diptera and present in all nematocerous Diptera other than Culicomorpha and Nymphomyiidae, indicating that it is correctly identified as synapomorphic for this lineage. However, it is important to know that an ejaculatory apodeme has been previously identified in Mecoptera but there are questions of homology with that found in Diptera (Sinclair et al, 2007). Further to this, the absence of an ejaculatory apodeme in Culicomorpha is almost certainly related to the presence of a spermatophore, a different mechanism to deliver sperm, which is considered a derived condition within the Diptera and quite possibly derived from a lineage with an ejaculatory apodeme.…”