0000000000080737
AUTHOR
Cusumano A.
Nuovi ritrovamenti di resti di vertebrati nel travertino di Alcamo (TP).
I depositi di travertino di Alcamo (TP) sono noti sin dal 1928 soprattutto per aver restituito resti dell’elefante di piccola taglia Paleoloxodon falconeri. Intorno agli anni ’80 nella cava di Contrada Cappuccini i lavori di coltivazione portarono alla luce una grossa frattura nel travertino. La frattura, riempita di un paleosuolo e chiaramente successiva alla formazione del travertino, conteneva un’associazione fossile caratterizzata dalla presenza di Paleoloxodon mnaidriensis. Il fatto che il paleosuolo contenga tali resti, assenti nel bancone di travertino caratterizzato invece dalla presenza dell’elefante di piccola taglia, costituisce un'inoppugnabile prova stratigrafica sulla successi…
Volatiles from Maruca vitrata (Lepidoptera, Crambidae) host plants influence olfactory responses of the parasitoid Therophilus javanus (Hymenoptera, Braconidae, Agathidinae)
Plants damaged by herbivores are known to release odors attracting parasitoids. However, there is currently no information how leguminous plants damaged by the pod borer Maruca vitrata attract the exotic larval parasitoid Therophilus javanus, which was imported into Benin from the putative area of origin of the pod borer in tropical Asia for assessing its potential as a biological control agent. In this study, we used Y-tube olfactometer bioassays to investigate T. javanus response towards odors emitted by four M. vitrata-damaged host plants: cowpea Vigna unguiculata, the most important cultivated host, and the naturally occurring legumes Lonchocarpus sericeus, Sesbania rostrata and Tephros…
The occurrence of the extinct shark genus Sphenodus in the Jurassic of Sicily
During the systematic revision of some historical collections containing Mesozoic ammonites, housed at the "G.G. Gemmellaro" Geological Museum of the Palermo University, a fossil shark’s tooth has been discovered. This specimen, indicated as Lamna in the original catalogue, can be attributed to the genus Sphenodus, an extinct cosmopolitan shark ranging from Lower Jurassic rocks to the Paleocene. The specimen is part of the Mariano Gemmellaro Collection which mainly consists of Middle-Upper Jurassic ammonites coming from Tardàra Mountain, between Menfi and Sambuca di Sicilia (Agrigento Province, Southwestern Sicily). Some of the ammonite specimens were listed, but not illustrated, by M. Gemm…
Chemical Ecology of Floral Resources in Conservation Biological Control.
Conservation biological control aims to enhance populations of natural enemies of insect pests in crop habitats, typically by intentional provision of flowering plants as food resources. Ideally, these flowering plants should be inherently attractive to natural enemies to ensure that they are frequently visited. We review the chemical ecology of floral resources in a conservation biological control context, with a focus on insect parasitoids. We highlight the role of floral volatiles as semiochemicals that attract parasitoids to the food resources. The discovery that nectar-inhabiting microbes can be hidden players in mediating parasitoid responses to flowering plants has highlighted the co…
Western European Populations of the Ichneumonid Wasp Hyposoter didymator Belong to a Single Taxon
Hyposoter didymator (Hymenoptera, Ichneumonidae) is a generalist solitary endoparasitoid of noctuid larvae. In the present work, we tested whether populations of H. didymator were divided in several genetically distinct taxa as described for many other generalist parasitoid species, and whether differences in H. didymator parasitism rates were explained by the insect host species and/or by the plant on which these hosts were feeding on. The genetic analysis of natural populations collected in different regions in France and Spain on seven different insect hosts and seven different host plants (775 individuals) showed that H. didymator populations belong to a unique single taxon. However, H.…
How to escape from insect egg parasitoids: A review of potential factors explaining parasitoid absence across the Insecta: Escape from insect egg parasitism
The egg is the first life stage directly exposed to the environment in oviparous animals, including many vertebrates and most arthropods. Eggs are vulnerable and prone to mortality risks. In arthropods, one of the most common egg mortality factors is attack from parasitoids. Yet, parasitoids that attack the egg stage are absent in more than half of all insect (sub)orders. In this review, we explore possible causes explaining why eggs of some insect taxa are not parasitized. Many insect (sub)orders that are not attacked by egg parasitoids lack herbivorous species, with some notable exceptions. Factors we consider to have led to escape from egg parasitism are parental egg care, rapid egg deve…