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The Panchaetothripinae comprises 42 genera and 146 species of leaf-feeding thrips, some of which are horticultural pests. We examined representatives of the 18 genera that include most of these pests. For species delimitation, we used DNA barcoding to produce171 sequences for 40 morphospecies. Most species were found to be monophyletic, although cryptic diversity was evident in 8 presumptive species. A multilocus molecular phylogenetic assessment was based on one mitochondrial (COI) and three nuclear loci (EF-1α , ITS2, and 28S) from 132 specimens (18 genera and 33 species), representing all genera and ~82% of species in China. Maximum likelihood (ML) and Bayesian inference (BI) confirmed monophyly of each genus with strong support. Monophyly of tribes Panchaetothripini and Monilothripini were refuted, but the well supported tribe Tryphactothripini was confirmed. Rhipiphorothrips was recovered as a sister to the remainder of the genera of Panchaetothripinae combined. Both analyses revealed two major clades. Clade A comprised the majority of the genera, including tribe Tryphactothripini. Clade B included only four genera of which two, Helionothrips and Caliothrips , are particularly species rich. The relationships of some genera remain unresolved. [ABSTRACT FROM AUTHOR]

Buffel grass (Cenchrus ciliaris) is a perennial tussock grass native to parts of Africa and southern Asia but is now distributed throughout much of mainland Australia. Corresponding with its presence in Australia has been an alteration of fire regimes and soil nutrients, and a reduction in floral diversity. We investigated whether buffel grass supported a less diverse community of thrips (order Thysanoptera) compared to the native grasses Cymbopogon ambiguus and Themeda triandra growing in Alice Springs, central Australia. The survey data showed that abundance was highest on buffel grass; however, the thrips community was almost entirely dominated by one species. The thrips communities on the native grasses were similar and markedly more diverse than that on buffel grass, both in terms of species richness and functional feeding groups. Flower feeders constituted the greatest proportion of thrips on all three grasses, but the native grasses also supported leaf feeders and predators. The results indicate that thrips are sensitive to vegetation change, and we suggest that active removal of buffel grass and replacement with local native grasses would help reverse the loss of biodiversity and normal ecological function in urban areas like Alice Springs. We also suggest that the order Thysanoptera is under-utilised in biodiversity research. [ABSTRACT FROM AUTHOR]

Thrips (Thysanoptera) are opportunistic insects that exhibit a wide range of life histories. Most species are either fungivorous or phytophagous, while a few are predators. In coffee agroecosystems, the presence of these insects is noticeable, especially when coffee is flowering. The identity of thrips and the role they might be playing on coffee flowers is unknown. We conducted a survey of thrips in 30 commercial coffee plantations of Chiapas, Mexico, with the aim to investigate the species composition of thrips associated with coffee flowers and to determine whether they were carrying coffee pollen on their bodies. Thrips were collected at random in ∼1 ha. Coffee branches were shaken against a plastic tray to separate insects from flowers. A total of 42 thrips species in 24 genera and five families were identified. The most common species were Karnyothrips merrilli Watson, Haplothrips gowdeyi (Franklin), Frankliniella difficilis Hood, Frankliniella gardeniae Moulton, Frankliniella insularis (Franklin), Frankliniella invasor Sakimura, Frankliniella parvula Hood, and Frankliniella varipes Moulton. Of these species, Karnyothrips merrilli is considered a predator of thrips and other small arthropods, while the other species are phytophagous. We assumed these thrips might be living on other plants and shift to coffee due to the abundance of pollen and nectar during the flowering season. Using microscopy, we examined the bodies of thrips caught in sticky traps. We found coffee pollen on the bodies of seven thrips species, and discuss the possibility of these thrips serving as coffee pollinators. [ABSTRACT FROM AUTHOR]

Most Thysanoptera possess a haplo-diploid reproductive mode and reproduce via arrhenotoky. Females can mature eggs successively throughout almost their entire life, but in most terebrantian thrips spermiogenesis is complete by adult male eclosion, and testes contain only mature spermatids. In parasitoid wasps this phenomenon of preadult spermiogenesis is described as prospermatogeny. It is unclear if prospermatogeny and this predetermined sperm quantity have implications for mating strategy and fitness. In this study, we give a detailed description of mating behavior of the thripine species Echinothrips americanus, which largely corresponds with the only available data of another species of this family, Frankliniella occidentalis (Thysanoptera: Thripidae). With investigations using light microscopy, we describe for the first time the chronological sequence of internal processes during copulation. The release of male accessory gland material followed subsequently by spermatozoa indicates production of a female-determined type 1 spermatophore. Despite prospermatogeny, males are able to inseminate 10 females with an equal amount of spermatozoa. It is only the quantity of glandular material that decreases with the number of previous copulations. Based on these new findings, the reproductive strategy of this species is discussed. [ABSTRACT FROM AUTHOR]

The insects known as thrips are commonly thought of as flower-living and pestiferous organisms, but we report here a novel interaction between a phlaeothripine thrips species, Mirothrips arbiter gen. et sp. nov. and three species of social paper wasps in Brazil. This thrips species breeds inside the wasp colonies, and larval and adult thrips feed on wasp eggs, which become severely damaged. Infested nests can contain up to 300 M. arbiter gen. et sp. nov. individuals. The closest relatives of M. arbiter are two presumably predaceous species: Mirothrips bicolor sp. nov., which inhabits abandoned Cecidomyiidae galls, and Mirothrips analis comb. nov., described from individuals collected in the silken bags of the caterpillars of Psychidae moths. The behaviour exhibited by M. arbiter represents one of the most evolutionarily advanced lifestyles known among Thysanoptera, and we predict that other polistine species serve as hosts for this thrips in Brazil. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109, 332-341. [ABSTRACT FROM AUTHOR]

Akainothrips francisi sp. nov. is shown to be an inquiline (i.e. it invades, and breeds within, domiciles of another species). Currently, its only known host is Dunatothrips aneurae, a subsocial thrips that creates silken domiciles by securing together phyllodes of mulga ( Acacia aneura) in the arid zone of Australia. We found Ak. francisi prolifically breeding inside live D. aneurae host domiciles, both immature and mature. Akainothrips francisi did not kill its host and we saw no evidence of antagonistic host-inquiline interactions. This is thus the second demonstrably inquiline species of Acacia thrips, although other possible inquilines have been suggested including two Akainothrips. We found that Ak. francisi occurred with positive density dependence, and was associated with moderately reduced host reproduction. This latter association was especially evident in larger host domiciles, suggesting that Ak. francisi either inhibits further host reproduction after invasion or exploits poor quality hosts more successfully. Sex ratios were slightly female biased. Akainothrips francisi males were exceptionally variable in size, colour, and foreleg size compared to females, with morphs co-occurring within domiciles, suggesting sexual selection and the possibility of different male reproductive strategies. The discovery of Ak. francisi highlights particular morphological affinities among known or suspected inquiline Acacia thrips within Akainothrips and other genera, allowing us to hypothesize a common origin of this lifestyle from within Akainothrips. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ••, ••-••. [ABSTRACT FROM AUTHOR]

The western flower thrips, Frankliniella accidentalis(Pergande); flower thrips, Frankliniella tritici (Fitch) ; and tobacco thrips, Frankliniella fusca (Hinds), are abundant, polyphagous species in the southern United States. Paspalum notatum Flugge and Paspalum distichum L. (Poales: Poaeeae) are low-maintenance, warm-climate, tolerant grasses that are used for pasture and residential lawns and along roadsides. The potential of P. notatum and P. distichum to serve as sources of the common polyphagous Frankliniella thrips in the southeastern United States was evaluated. The abilities of F. fusca, F. occidentalis, and F. tritici to survive and reproduce on vegetative-stage P. distichum, P. notatum 'Argentine', P. notatum 'Pensacola', and P. notatum 'Tifton 9' were compared in laboratory no-choice tests. Survival of the adults of each thrips species was ≈20% after 12 d on each of the Paspalum treatments. No progeny were produced by F. occidentalis on the U.S. native P. distichum, and the other thrips species produced very few progeny on this host. The number of progeny of each thrips was very low on all P. notatum cultivars. A field survey of the Thysanoptera associated with P. notatum Argentine also was conducted to determine whether the Frankliniella thrips were feeding or reproducing under field conditions. A few male and female adults of F. tritici and F.fusca were noted in the racemes, but larval populations were not observed. Reproducing populations of Caprithrips insularis Beshear and Haplothrips graminis Hood were present in the stems and leaves, and the racemes, respectively. Collectively, the laboratory and field studies revealed that the tested P. notatum cultivars and P. distichum accession are poor hosts for reproduction of the Frankliniella thrips in the southern United States and that the large plantings of these grasses are not serving as sources of pest Frankliniella thrips. [ABSTRACT FROM AUTHOR]

The article discusses a study on a new species of Charassothrips Hood from Colombia. This new species was taken from several different plants near Bogota, Colombia, from Asteraceae flowers that are very different in form from the known hosts of other species of Charassothrips. Variation between species within this genus was interesting, including the number of antennal segments, the form of the major setae, the body color, and the markings within the surface reticulation.

Populations of the invasive Frankliniella occidentalis (Pergande) are serious pests of agricultural crops in the Aconcagua Valley of central Chile. An extensive survey was conducted of 55 plant species in 24 families to identify plant hosts of F. occidentalis and to determine its relative abundance on each host during each season. A more intensive study was conducted on selected plant species serving as reproductive hosts to determine the population dynamics of F. occidentalis and to evaluate the potential importance of Onus species and other natural enemies for controlling F. occidentali.c. Adults of F. occidentali.s were active during each season of the year inhabiting the flowers of 91% of the sampled plant species in 22 families, and 86% of these plant species in 19 families served as reproductive hosts. The number of host plant species used was greatest in the spring and least in the winter. All of the hosts except Medicago sativa L. were used only when flowering. Populations of F. occidentalis were significantly aggregated in M. sativa in the terminal buds over the leaves when the host was not flowering, and in the flowers, followed by the terminal buds, followed by the leaves when the host was flowering. Larvae were 1.3-2.3 times more abundant on dates when M. sativa was flowering. There were no identifiable patterns in plant hosts based on endemicity or plant family. Most of the plant species used by F. occidentalis were inferior quality hosts where populations either declined or were stable. Populations of F. occidentalis on low-quality hosts generally escaped predation by Onus species and competition by other species of thrips. Only 25% of the food hosts and 28% of the reproductive hosts for F. occidentalis in the extensive survey, respectively, were host plants for Onus. Parasitoids and other predators were not found to be important in suppressing thrips on any of the plant hosts. Populations of F. occidentali.s increased on only a few hosts, including M. sativa and Sisymbrium officinale L. Scop. These apparently are major sources of F. occidentalis adults invading crops. We conclude that F. occidentalis is established in central Chile and that it has replaced and possibly displaced the native Frankliniella australis (Morgan) as the most common thrips species. [ABSTRACT FROM AUTHOR]

Results of analyses of molecular sequence (COI, 28S-D2) and morphology (21 character states) data, both alone and combined, were used to determine relationships between 18 species of Scirtothrips (Thysanoptera: Thripidae, Thripinae). Two species of Neohydatothrips from Panama were used as the outgroup. Five major pest Scirtothrips were included in these analyses: S. aurantii, S. citri, S. dorsalis, S. kenyensis, and S. perseae. Trees generated from a parsimony analysis of molecular data and Bayesian analysis of molecular and morphology data combined showed high levels of congruence. The morphology-only tree had several differences in species groupings when compared with trees derived using molecular data. Both parsimony and Bayesian analyses using molecular data indicated that Scirtothrips species associated with avocados were monophyletic, a result not observed with morphological analyses. No support was found for a monophyletic S. dorsalis clade when sampled from six different countries. The S. dorsalis complex may be comprised of at least three separable groups identifiable at the molecular level, but indistinguishable morphologically. The implications of this finding for S. dorsalis, a thrips pest of global significance with high invasion potential, are discussed. [ABSTRACT FROM AUTHOR]

Effective plant quarantine and biological control initiatives require rapid and accurate identification of exotic and potentially invasive taxa that may cause high economic losses or environmental damage. The genus Scirtothrips Shull includes several species that are serious agricultural pests, and, because of their minute size and cryptic behavior, prone to undetected transport through international trade of plant material. Although assigning specimens to the genus Scirtothrips is straightforward using traditional taxonomic methods, identification of species is much more difficult and requires expert knowledge of the genus. Furthermore, the validity of some Scirtothrips species is questionable. Therefore, an easy, accurate, and highly reliable technique is desirable for Scirtothrips identification. Here, we provide a simple molecular key based on the internal transcribed spacer regions 1 and 2 (ITS 1 and ITS2) of nuclear ribosomal DNA. Individual specimens can be identified by amplification of their ITS1 and ITS2 regions with general primers and determining the size of the products by using standard agarose gel electrophoresis, followed in some instances by DNA digestion with the restriction enzymes Sad or PspOM I. The advantage of this identification system is that nonspecialists are able to quickly and cheaply identify individual specimens. Material analyzed for this work was collected in the United States (California), India, South Africa, Kenya, Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, Panama, Australia, New Zealand and Raiatea (Society Islands French Polynesia). We have identified seven pest species with the molecular-based methods described here. It is hoped that this system can be extended to other members of the genus as their ITS1 and ITS2 sequences become available. We also provide molecular confirmation for two new Scirtothrips species, one species from Honduras and one species from New Zealand. [ABSTRACT FROM AUTHOR]

Kladothrips rugosus Froggatt has previously been considered a single polyphagous species that, in Australia, induces galls on several species of Acacia, with the gall structure varying both within and between hosts. On Acacia papyrocarpa, two types of gall are induced by this species, one with the surface ridged but the other with the surface smooth. Using sequence data from cytochrome oxidase subunit I (CO I) and elongation factor-1 alpha gene fragments, we show that the thrips inducing these two gall-types are genetically distinct and comprise separate lineages. Uncorrected ‘ p’ distances calculated from CO I gene fragments were 0.000 and 0.006 within lineages and 0.074 and 0.078 between lineages. The between-lineage distances are comparable with distances between morphologically distinct species of other Acacia gall-thrips. Re-examination of adult thrips from the two gall types revealed consistent differences in body colour, as well as in body sculpture. Together with observations on gall founding behaviour, these data indicate that the thrips populations in the two gall types on A. papyrocarpa are reproductively isolated and should be considered as separate species. The form from smooth galls on A. papyrocarpa is therefore described as Kladothrips nicolsoni sp. nov., although the form from ridged galls can be considered only as ‘ K. rugosus agg.’. These inconsistencies in the taxonomic status of the various units within the K. rugosus species complex are discussed, although most of them cannot be distinguished morphologically at present. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 88, 555–563. [ABSTRACT FROM AUTHOR]