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Thirty-nine species of terebrantian Thysanoptera belonging to four families and 22 genera are here recorded from the Maltese Islands. Of these, 33 represent new records to this archipelago. Thrips were collected from 65 different locations over a seven-year period, covering the main habitat types found across the Maltese Islands, namely steppe, garigue, maquis and woodland, but also sand dunes and saltmarshes as well as roadsides, private and public gardens, greenhouses and cultivated fields. An illustrated dichotomous key to identify the Terebrantia of the Maltese Islands is presented. Chorological data for the species researched in the current study shows that the majority of these insects are of a European Mediterranean origin, though the geographical distribution of some of them extends to Africa and the Middle East. Seven species associated with agricultural commodities were found to be of alien origin; however they were locally found in small numbers and do not pose a threat to horticulture.

Four species of phlaeothripines are newly recorded and illustrated from New Caledonia: Adraneothrips moundi n. sp., Baenothrips cf. cuneatus Zhao & Tong, Leichhardtithrips evanidus Tree & Mound and Sophiothrips typicus (Ananthakrishnan). The male of L. evanidus is recorded for the first time.

Four species of Teuchothrips are recognised as endemic to New Caledonia and distinct from the many species of this genus in Australia. Three of these species are shown to have a variable number of sense cones on antennal segment IV, in contrast to most recorded species in the Liothrips-lineage. One endemic species is removed from Teuchothrips and considered here as Neocecidothrips pacificus (Bianchi) comb.n. together with illustrations and diagnostic notes. A key is provided for the four Teuchothrips species known from New Caledonia.

Thrips (Thysanoptera) are opportunistic organisms that exhibit a wide range of life histories. Although easily overlooked because of their small size, they have been recorded from many types of ecosystems worldwide (Mound 2005). The thysanopteran fauna comprises~6,000 species and is more abundant and diverse in thetropics than in temperate regions (Mound and Marullo1996).

The Pacific island of New Caledonia is located about 1500km East of Australia just north of the Tropic of Capricorn. It has a rich endemic flora involving more than 5000 plant species (Endemia.nc 2021; Guillaumin 1948), but the only account of the Thysanoptera fauna apart from some new species descriptions is a check-list of 44 genera and 68 species (Bournier & Mound 2000). Here we describe a new monotypic genus of Panchaetothripinae that has been collected twice in New Caledonia, in 1992 and 2012, but without any information on possible host associations. This genus shares character states with a monobasic genus from New Zealand, but more particularly with a genus of four species endemic to Australia. The Thripidae fauna of New Zealand appears to be well-studied (Mound et al. 2017), with only one or two undescribed species known in collections. The Australian Thysanoptera fauna has also been studied extensively in the past 20 years (Mound & Tree 2020), and few undescribed species of Thripidae are known. In contrast, the Thysanoptera fauna of New Caledo-nia appears to be largely unexplored, and description here of this new genus serves to emphasize the uniqueness of this fauna. Photographs of the habitus and morphological characters were taken on the technical platform at CBGP (Centre de Biologie pour la Gestion des Populations) using a KEYENCE® VHX-5000 digital microscope and a Leica DM5500, and at CSIRO, Canberra using a Leica DM2500 with Nomarski illumination.

The composition and structure of thrips populations were determined in agroecosystems of 10 crops in the Andean, Caribbean, and Orinoquia regions of Colombia. From 18,183 identified specimens, 81 species belonging to 20 genera and three families were found. The Andean region was the most diverse with 60 species (n = 11,360, Chao 1 = 70.5, H′ = 1.986), followed by the Caribbean region with 42 (n = 5,960, Chao 1 = 57.6, H′ = 2.256) and the Orinoquia with 24 (n = 863, Chao 1 = 31; H′ = 2.301). The crop with the richest fauna was avocado (Persea americana) Mill. with 40 species (n = 4,047, Chao 1 = 55.17, H′ = 1.302), followed by coffee (Coffea arabica) L. with 26 (n = 1,395, Chao 1 = 33; H′ = 1.026), cassava (Manihot esculenta) Crantz. with 25 (n = 1,050, Chao 1 = 29.67, H′ = 1.635), citrus (Citrus spp.) with 22 (n= 836, Chao 1 = 25.75, H′ = 1.748), corn (Zea mays) L. with 22 (n = 1,647, Chao 1 = 24.5, H′ = 1.365), mango (Mangifera indica) L. with 17 (n = 1,144, Chao 1 = 18.5, H′ = 1.303), blackberry (Rubus glaucus) Bentham. with 11 (n = 545, Chao 1 = 16, H′ = 0.886), banana (Musa spp.) with 9 species (n = 1,798, Chao 1 = 9, H′ = 0.208), cotton (Gossypium hirsutum) L. with 8 (n = 5,621, Chao 1 = 11, H′ = 0.913), and rubber tree (Hevea brasiliensis) Müll.Arg. with 4 species (n = 90, Chao 1 = 4, H′ = 0.594). Differences were found in the distribution of the species in the altitudinal gradients and in the biogeographical regions. Frankliniella gardeniae Moulton, was the most abundant species, with the highest presence in crops, the greatest geographic and altitudinal distribution.

Entomopathogenic fungi such as Beauveria spp. have potential applications in the biocontrol of insect pests but little is known regarding their infectivity to the pine weevil Pissodes nemorensis. In this study, five isolates of Beauveria pseudobassiana and five isolates of Beauveria bassiana were tested for characteristics correlating with virulence on P. nemorensis. Isolate UAMH301 had the lowest mean lethal concentration value whereas the highest value was obtained with isolate LRC137. Growth rate was negatively correlated with virulence in B. bassiana, because isolate LRC137, the least virulent isolate, grew much more rapidly than the other B. bassiana isolates on SDYA. In contrast, its growth on a hyperosmotic medium was the slowest. Sporulation rate and conidial area were not correlated with virulence. Mycelial cell density was positively correlated with virulence in both species, and the four tested genes appear to be one-copy genes. Bbchit1 and Bbhog1, genes respectively encoding a chitinase and a protein kinase, induced relative expression levels were positively correlated with virulence in B. pseudobassiana. We discuss in terms of previous morphological, physiological and genetic parameters related to virulence in Beauveria and the importance of testing the expression of putative virulence genes in comparison with their basal transcript levels.

The response of Culicoides biting midges, mosquitoes and other dipterans to different wavelengths was evaluated in a farm meadow in northern Spain. A total of 9449 specimens of 23 species of Culicoides, 5495 other ceratopogonids (non-biting midges), 602 culicids and 12428 other mixed dipterans were captured. Centers for Disease Control and Prevention (CDC) suction light traps fitted with five light emitting diodes (LEDs) (white, green, red, blue, ultraviolet) were run for 15 consecutive nights. Significantly more Culicoides were collected in those traps fitted with green, blue or ultraviolet (UV) lights than in red and white-baited LED traps for the most abundant species captured: C. punctatus (37.5%), C. cataneii (26.5%) and C. obsoletus/C. scoticus (20.4%). Similar results were obtained for non-Culicoides ceratopogonids, mosquitoes and other mixed dipterans. Wavelengths in green (570 nm) resulted effective for targeting some Culicoides species, culicids and other midges. In a second trial, the effectiveness of 4-W white and UV tubes was compared to traps fitted with UV LED and a standard incandescent light bulb. More specimens of all taxa were collected with fluorescent black light (UV) traps than with the other light sources, except culicids, which were recovered in high numbers from fluorescent white light traps.

Some twig beetles in the genus Pityophthorus (Coleoptera: Scolytinae) may vector pitch canker disease Fusarium circinatum (Niremberg & O'Donnell) of Pinus spp. (Pinaceae). Because Pityophthorus pubescens (Marsh.) has been found to be associated with F. circinatum in the Basque Country (northern Spain), various experiments were conducted to assess the beetle's behavioural responses to (E, E)-alpha-farnesene, (R)-(+)-limonene and (S)-(-)-verbenone to develop a potential inhibitor to host attraction. These experiments comprise electroantennographic and double-choice olfactometer tests, as well as field assays in Pinus radiata D. Don stands. RESULTS: Both sexes of P. pubescens showed similar electroantennographic responses to different doses (from 1 ng to 1 mu g in decadic steps) of each individual compound, with depolarisations to (S)-(-)-verbenone (100 ng) being similar to those of the aggregation pheromone (+)-trans-pityol. In olfactometer assays, both sexes were significantly attracted to (+)-trans-pityol, but the attraction was reduced when increasing amounts of the chemicals were added to the pheromone. Particularly relevant was the repellent effect induced by (S)-(-)-verbenone at 1 ng dose and higher. In the field, (E, E)-alpha-farnesene, (R)-(+)-limonene and (S)-(-)-verbenone reduced significantly the number of beetles attracted to (+)-trans-pityol and racemic trans-pityol, with (S)-(-)-verbenone being the most effective. CONCLUSIONS: (S)-(-)-Verbenone showed an interesting potential for use in the protection of P. radiata stands. A potentially effective strategy, which could be implemented in further, more in-depth studies, could involve the use of this semiochemical as repellent and (+)-trans-pityol-baited traps as attractant in a push-pull strategy. Copyright (c) 2012 Society of Chemical Industry

The chemical profile of the cuticle and internal tissues of four species of Culicoides have been studied for the first time by gas chromatography-mass spectrometry. The chemical composition of females of C. obsoletus s.l. and C. lupicaris, vectors of diverse viral diseases, have been compared with that of other biting midges, such as C. kibunensis and C. fascipennis, and the non-biting midge Forcipomyia bipunctata. A total of 61 compounds belonging to 8 major chemical classes were identified in cuticular and internal tissues in n-hexane extracts. The compounds include carboxylic acids (CAs) (C6-C20), with C16:0, C16:1 and C18:1 being dominant, branched hydrocarbons (C29 to C38 mono/di/trimethylalkanes), linear hydrocarbons (C15 to C33, mainly odd chain carbons), terpenes (geranylacetone, geranylgeraniol acetate, squalene, terpenic alcohol), steroids (cholesterol), aldehydes (C9-C10 and even chain C20 to C30), and esters. The chemical profile depends on the species and whether the extracts are external (cuticle) or internal. The contents of linear and branched hydrocarbons and aldehydes was high in cuticular extracts but practically absent in internal tissues, which were, in contrast, rich in CAs, terpenes and steroids. The results are discussed and compared with other Culicoides midges and mosquito-related species.

We present evidence favoring the use of (E )-pityol as an aggregation pheromone in Pityophthorus pubescens (Marsham). (E )-Pityol was detected in effluvia of male and female P. pubescens, and antennae of both sexes responded to (E )-( )-pityol in electroantennogram assays. In two-choice olfactometer tests, males significantly preferred (E )-( )-pityol and (E )-(9)-pityol to blank controls at doses of 1, 10, and 100 ng, whereas females only showed a preference for (E )-pityol at the 1 ng dose.