Abstract. The systematics of tribe Schistopterini (Diptera: Tephritidae) is reviewed and discussed, and a key is given to the fourteen current genera, of which four are new. A cladogram of the type species of the genera plus all other species of one of the new genera (Microtreta) is presented, supporting the monophyly of Microtreta. The new genera include Calloptera (type species Rhabdochaeta asteria Hendel), Microtreta (type species Microtreta fini, sp.n.), Melanopterella (type species Rhabdochaeta nigra Bezzi) and Schistotephritis (type species Camaromyia acrophthalma Bezzi). Microtreta is treated comprehensively; its constituents, deemingi, fini, frontale, jeffreyi and longicornis (all new species), are described from East Africa and the Arabian Peninsula. Host plants, all of genus Vernonia (Asteraceae), are recorded for the four East African species. Characters of immature stages are described for M. longicornis. Eighteen new combinations are made.

The little fire ant, Wasmannia auropunctata, probably arrived in Israel in ca. 1998 and was identified in 2005; this is the first record of this species from open areas outside the tropics and subtropics. It survives harsher conditions than in its native habitats, with minimal annual temperatures as low as 6°C, and 5-12 consecutive rainless months (under 15 mm rainfall per month). It is now known from 26 localities in Israel, mostly in irrigated gardens. As in other regions where they have invaded, these ants pose a serious threat to local biodiversity. At high densities they displaced almost all the local ant species sampled, affecting population abundances, species richness, and community structure. W. auropunctata seems to have a detrimental effect also on other ground arthropods, judging from the observed decline in spider and beetle abundances. We show here that this tropical species can pose a critical threat to local arthropods at a wider range of climatic conditions than was previously known.

We report results of field collections, laboratory rearing, and behavioral observations of tephritids belonging to the tribes Acanthonevrini and Gastrozonini in Malaysia and Thailand. The focus of the study was on general biology, seasonal history, mating, oviposition, larval biology, larval habits, and microhabitats. Host association with bamboo was unequivocally established for 31 species. Adult flies fed on liquids oozing from plants or other sources. Most species developed in the rainy season, when bamboo shoots were available. In Thailand, adult flies gathered along streams in the dry season. Observed sexual behavior patterns appeared to be simple in Gastrozonini, whereas in some Acanthonevrini, the males produced a foamy “nuptial gift,” which was offered to females during courtship. Eggs were laid under sheaths or in injuries to the bamboo surface. The main obstacle to oviposition and penetration of shoots appeared to be the hard culm sheaths.Thelarvae entered feeding substrates via injuries, holes created by other insects, or by squeezing in between culm sheaths and bamboo walls. Larvae of Gastrozonini and Rioxoptilona (Acanthonevrini) fed on living or dead bamboo shoots. Larvae of other Acanthonevrini developed in water-filled internode cavities, scraping particles from walls or collecting them from the water surface. Bamboo growth stages and degree of protection by culm sheaths were used to classify microhabitats. These determined to a large extent which guilds of flies could be found. While larvae of some bamboo tephritids destroyed thin bamboo shoots or branches, most acted as secondary pests and did not cause substantial economic losses.

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Abstract.  1. The sex determination mechanism in gall midges is little understood, although it is known that the females of several species primarily or exclusively produce unisexual broods throughout their lifetime. 2. The gall midge Izeniola obesula Dorchin is a multivoltine species, inducing multi‐chambered stem galls on the salt‐marsh plant Suaeda monoica. Each gall contains 5–70 individuals, all being the progeny of a single female. Sampling of more than 450 galls, from which adult midges were reared, suggested that I. obesula exhibits strict monogeny, resulting in galls that contain either all female or all male progeny. 3. Characterisation of the growth pattern of young S. monoica shoots revealed that shoots in apical positions grew more rapidly than shoots in more basal positions. Galls that were induced on such shoots were larger and yielded more adult midges. 4. No difference in the site of gall induction was found between male and female galls, with galls of either sex being mainly induced on more rapidly growing shoots. It is concluded that I. obesula females cannot control the sex of their progeny, and that both female‐producers and male‐producers strive to maximise their reproductive success by choosing the faster‐growing shoots for gall induction. 5. Female galls were larger and more abundant than male galls at almost all times. The sex ratio among galls fluctuated throughout the year, ranging from 4:1 in spring to 1:1 in winter. The skewed sex ratio among galls possibly results from greater mortality rates among male galls than among female galls, due to either primary or secondary factors. Alternatively, it is possible that the number or fitness of male‐producers in the population is reduced relative to female‐producers.