---

Hi Gordon,

Schumann et al. (1999) mention the following approx. world species numbers, but might be somewhat outdated:

Rhagionidae ~560
Xylomyidae ~105
Xylophagidae ~70


You may have a look at the BDWD, which give also a good guess, but keep in mind the status column for each family (cf. quality assurance).

Recently, a paper dealing with the global diversity of freshwater Diptera was published (Wagner et al. 2008), which might be of interest.

so long,
xylo

btw: you have post.....


literature cited:

Schumann, H.; Bährmann, R. & Stark, A. [eds.] (1999): Entomofauna Germanica 2. Checkliste der Dipteren Deutschlands. - Studia dipterologica Supplement 2: 1-354.

Wagner, R. et al. (2008): Global diversity of dipteran families (Insecta Diptera)in freshwater (excluding Simulidae, Culicidae, Chironomidae, Tipulidae and Tabanidae). - Hydrobiologia 595:489-519.