In spite of its incidence on pistachio trees, the chemical ecology of Labidostomis lusitanica (Germar) (Coleoptera: Chrysomelidae) has been neglected so far. In this work, we provide the first evidence of a biologically active male-specific compound that may be promoting field aggregation. Headspace collections through solid-phase microextraction from feral males and females reported the presence of 2-isobutyl-3-methoxypyrazine exclusively in males. Electroantennographic recordings revealed that males and females responded in a dose-dependent manner to increasing stimuli of 2-isobutyl-3-methoxypyrazine, with females overall displaying a higher response than males. In dual-choice tests, both males and females showed a significant preference for the compound in comparison to a pure air stimulus. In light of these results, the possible role of 2-isobutyl-3-methoxypyrazine as an aggregation cue in L. lusitanica is discussed.
Se presentan los resultados de diversos muestreos llevados a cabo sobre parcelas cultivadas de pistachero en diferentes localidades de Castilla – La Mancha, en las provincias de Ciudad Real, Cuenca y Toledo. Se han encontrado un total de 8 especies de Curculionidae, de 5 géneros (Brachyderes, Otiorhynchus, Polydrusus, Sitona y Lixus) correspondientes a 2 subfamilias: ENTIMINAE y LIXINAE. Brachyderes marginellus, B. pubescens, Polydrusus subglaber, Otiorhynchus cribricollis y Lixus acicularis se han observado alimentándose de hojas de P. vera y se citan por primera vez sobre esta planta huésped. Polydrusus subglaber y Otiorhynchus cribricollis devoran intensamente sus hojas, por lo que se propone seguir investigando estas dos especies como importantes defoliadores de pistacho en la región. Se aportan datos biológicos y corológicos para las especies encontradas.
This study aims to characterize for the first time the insect assemblage associated with sown, introduced guayule (Parthenium argentatum A. Gray, Asteraceae) in Castilla-La Mancha, Spain, and identify potential relationships with the crop. Insect sampling was conducted using nets and pan traps during spring and early summer, coinciding with the flowering period of the plant. A total of 352 insect species/morphospecies across 12 orders were identified. Diptera, Coleoptera, Hemiptera, and Hymenoptera were the most species-rich and abundant orders. Within these orders, Muscidae, Syrphidae, Tenebrionidae, Dermestidae, Miridae, Halictidae, and Apidae were the most numerous families. Guayule flowering intensity increased gradually until mid-June, aligning with the peak activity of pollinating Diptera. The majority of the identified insects (74.4%) were potential pollinators, while nearly 50% were detritivores and approximately 30% were herbivorous. The similarity in insect families and functional roles observed in this study to previous studies in the USA and Mexico suggest that guayule may serve as a similar trophic resource for insects in Spain, despite being a non-native species.
In spite of its incidence on pistachio trees, the chemical ecology of Labidostomis lusitanica (Germar) (Coleoptera: Chrysomelidae) has been neglected so far. In this work we provide the first evidence of a biologically active male-specific compound that may be promoting field aggregation. Headspace collections by solid-phase microextraction from feral males and females reported the presence of 2-isobutyl-3-methoxypyrazine exclusively on males. Electroantennographic recordings revealed that males and females responded in a dose-dependent manner to increasing stimuli of 2-isobutyl-3-methoxypyrazine, with females overall displaying a higher response than males. In dual-choice tests, both males and females showed a significant preference for the compound in comparison to a pure air stimulus. In the light of these results, the possible role of 2-isobutyl-3-methoxypyrazine as an aggregation cue in L. lusitanica is discussed.
Se aportan nuevos registros de Sibinia exigua para Castilla-La Mancha (España Central), con ejemplares procedentes tanto de enclaves con vegetación halófila en varias localidades de la provincia de Ciudad Real, como de la colección histórica De la Fuente. Así mismo se han consultado sus manuscritos inéditos. Se aportan nuevos datos biológicos, especialmente de las plantas nutricias sobre las que se ha capturado.