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Summary Nymphomyia succina sp.n., the first fossil nymphomyiid fly (Diptera) from the Eocene Baltic and Bitterfeld amber is described and figured, based on four males. A probably conspecific female from the Baltic amber is also described and figured. With the discovery of this species, a gap in the distribution pattern of extant Nymphomyiidae is closed. It is probable that nymphomyiids colonized the eastern Nearctic Region via the Thule landbridge approximately 25–30 million years before present.

1-Acyl-4-benzylpyridinium salts 4 containing nonnucleophilic anions X– such as CF3SO3–, FSO3–, and BF4– can be generated quantitatively and in situ from 1-acyl-4-alkylidene-1,4-dihydropyridines 1a–f and the corresponding acid, HX. The BF4– salts reveal an interesting and unexpected thermal instability which allows the convenient synthesis of carboxylic acid fluorides 5b–f. This procedure offers advantages over known methods: All operations can be performed in a standard glass apparatus and do not require high pressures. The formation of RCOF 5 is assisted by the pyridine moiety of 4, which splits off and functions as a Lewis base to intercept the BF3 acid. The structural and electronic relationships as well as dominating differences between the very reactive cations of 4 and their almost “inert” uncharged precursors, the dihydropyridines 1, are discussed both on the fundament of experimental evidence (X-ray structures of 1f and the extremely reactive and very labile 4f) and theoretical investigations (ab initio and DFT MO calculations).

Chaetopteryx villosa Fabr. is uni- or semivoltine. The species was reared at 6°C and 10°C (8 h light, 16 h dark = LD 8/16) and at 10°C and 14°C (LD 14/10). Larval instar duration and pupal period decreased with increasing temperature. Instars II-IV were completed within 2-5 wk. Vth instar larvae pupated after two to twelve months. Pupal development required between one and three months. At 6°C no specimens pupated. At 10°C, LD 14/10 accelerated the development of instars II, IV, V and pupae. Head capsule widths were different between laboratory and field specimens. Relative consumption rate (RCR) ranged between 3.07 ± 1.12 (instar II, 14°C) and 0.09 ± 0.05 (instar V 6°C) mg mg-1 d-1. Growth rate, relative growth rate and efficiency of conversion were calculated. In a field experiment fine particulate versus coarse particulate organic material were tested as food sources. FPOM-fed specimens were smaller than those fed with FPOM + CPOM. Pupation was initiated earlier in the FPOM fed group and lasted longer than in the other groups.

Four species of Trichomyiinae are recorded from the Palaearctic region and a key to them is provided. Trichomyia urbica Haliday, T.parvula Szabo and the genitalia of T.itocoae Tokunaga & Komyo are redescribed. T.malkkyi sp.n., from Greece, is described. Detailed information is given on the structure of the sclerotized parts of the abdomen and on the internal genitalia of some Palaearctic, Nearctic and South American Trichomyiinae. The monophyly of some species-groups is briefly discussed, but the interrelationships of these groups remain obscure.

Die Umsetzung von tertiaren α-Hydroxy-ketonen mit Chlorsulfonylisocyanat, gefolgt von Verseifung mit Wasser, liefert die Carbamidsaureester 1--8. Diese werden durch thermische Cyclisierung in die Δ3-Oxazolone-(2) 9–14 ubergefuhrt. Reduktion von 9–14 mit Lithiumalanat fuhrt zu Oxazolidonen-(2) 15–20. Durch Verseifen mit Natronlauge werden 9–14 zu den Ausgangs-Hydroxyketonen gespalten. Synthesis and Properties of 3-Oxazol-2-ones Reaction of tertiary α-hydroxyketones with chlorosulfonyl isocyanate followed by hydrolysis with water yields the carbamates 1–8. These are converted into the 3-oxazol-2-ones 9–14 by thermal cyclisation. Reduction of 9–14 with lithium aluminum hydride leads to the 2-oxazolidones 15–20; saponification with sodium hydroxide produces the initial hydroxyketones.