Miguel Guara

GERMACRANOLIDES AND A MONOTERPENE CYCLIC PEROXIDE FROM ARTEMISIA FRAGRANS

Abstract The aerial parts of Artemisia fragrans collected in Armenia yielded a new cyclic monoterpene peroxide with the irregular santolinyl framework, together with several known germacranolides. Comparison with previously published chemical results suggests these may actually have been performed on a different, although closely related species.

Winter feeding leads to a shifted phenology in the browntail moth Euproctis chrysorrhoea on the evergreen strawberry tree Arbutus unedo.

1 The browntail moth Euproctis chrysorrhoea is a highly polyphagous univoltine forest pest. Although its young larvae usually overwinter in diapause from early autumn to the beginning of spring, winter larval feeding has been reported when this species feeds on the evergreen woody shrub strawberry tree Arbutus unedo. 2 The present study investigated life‐history traits of four populations of E. chrysorrhoea feeding on A. unedo, including phenology of the different life stages, larval feeding activity and diapause incidence. By modelling the relationship between larval size and host plant leaf persistence, elevation and mean annual temperature, we also studied larval development in ten populations of this species sampled from a range of geographical locations in Spain, from both A. unedo and deciduous hosts. 3 The results obtained revealed that on A. unedo, E. chrysorrhoea phenology has shifted: from October to March, A. unedo larvae doubled their size, whereas, on deciduous Ulmus minor and Quercus faginea, larval size did not change. General linear models demonstrated that such differences were not related to environmental variables. We also found that on A. unedo larval feeding was arrested for 2 months, with this period representing a true diapause. 4 The results obtained in the present study suggest that E. chrysorrhoea populations are phenologically adapted to their local host plants, and that the presence of foliage is a key element in the phenological shift reported on A. unedo. These results may have implications with respect to the formation of E. chrysorrhoea host races.

Age and size thresholds for pupation and developmental polymorphism in the browntail moth, Euproctis chrysorrhoea (Lepidoptera: Lymantriidae), under conditions that either emulate diapause or prevent it

Size and age thresholds for pupation are important life history traits of insects. They are the ultimate consequences of the underlying physiological mechanism that optimize resource allocation. Such thresholds may have a plastic response under time-varying environmental conditions, developmental polymorphism (i.e., plasticity in the number of instars before pupation) being a common strategy adopted by insects to overcome this challenging situation. In this study, we systematically explore the variables related with both age and size thresholds for pupation and developmental polymorphism in the browntail moth, Euproctis chrysorrhoea (Lepidoptera: Lymantriidae), by rearing a group of caterpillars under conditions that either emulate larval diapause or prevent it. As an innovative approach, we evaluated the importance of predictor variables by means of generalized linear modeling in a multi-model inference framework. Our results show that (i) rearing conditions affect fitness, (ii) rearing conditions, size of hatchlings, size and age at maturity and sex are related to the number of instars before pupation, and (iii) there are both age and size thresholds for pupation which differ between sexes and between larvae reared under different conditions. Results are discussed in the context of lepidopteran plasticity in life history traits and its relationship with optimal molting strategies.

DESCRIPTION OF THE FINAL INSTAR OF TRICHOMALOPSIS PEREGRINA (HYMENOPTERA, PTEROMALIDAE), WITH DATA AND COMMENTS ON THE PREIMAGINAL STAGES

Abstract The preimaginal stages of T. peregrina are described. The egg displays a sculptured chorion, which is found only on those deposited externally. The immature larvae are characterized by their peculiarities in (a) a setose ring on the thoracic and abdominal segments, (b) an anal notch and (c) size and the sensory structures of the head capsule. The final instar is described and illustrated. Morphological structures of diagnostic value are discussed. The most salient character shown by the mature larva of this species lies in the epistoma, which is complete.

Sesquiterpene lactones from Artemisia inculta

The aerial parts of Artemisia inculta collected in three different locations in Egypt have been chemically investigated. As a result, a new eudesmanolide and a new tetranorsesquiterpene lactone have been isolated, together with several known compounds. The chemical data available suggest the existence of distinct chemotypes for this species, but do not support its identity with other North African members of the genus.

Plastid DNA Homogeneity in Celtis australis L. (Cannabaceae) and Nerium oleander L. (Apocynaceae) throughout the Mediterranean Basin

Premise of research. Riparian plants are highly dependent on water sources; consequently, general climatic conditions are less important to these taxa relative to woodland and shrubland species. This leads to interesting research questions regarding riparian plant taxa. Research on phylogeography of Mediterranean riparian tree and shrub species is scarce. In this article, we investigated the plastidial genetic diversity in Celtis australis L. (hackberry) and Nerium oleander L. (oleander) throughout the Mediterranean Basin. Both species are distributed in gullies, rivers, and stream banks under warm temperate climates. Methodology. Eighteen cpSSR loci and three noncoding cpDNA regions (rps16, rpl32-trnL, and trnQ-5′-rps16) were examined to assess the levels and geographic distribution of sequence variation in 41 hackberry and 56 oleander populations. The rpl32-trnL intergenic region was used for molecular dating analysis. Pivotal results. The respective 2762- and 3134-bp noncoding cpDNA regions sequenced in C. australis and N. oleander, as well as the 22 cpSSR analyzed fragments, exhibited the absence of variability in natural populations throughout the Mediterranean Basin. In N. oleander, two regions (rps16, rpl32-trnL) exhibited variability in three positions, and four cpSSR microsatellite motifs were polymorphic. The polymorphisms were geographically structured, and three haplotypes were characterized, two from Saharan populations and one from Mediterranean populations. Phylogeny and molecular dating analyses resulted in a tree with high consistency values of posteriori probability (PP = 1) and bootstrap support (98%) from the ingroup (N. oleander). The relaxed molecular clock model applied to the calibration of the tree estimates that the diversification of these haplotypes occurred in a range of 7.2–1.2 Ma. Conclusions. The absence of plastid variability in both hackberry and oleander is explained by a low mutation rate and/or recent recolonization of the Mediterranean Basin. Low temperatures during the Last Glacial Maximum produced freezing water along riparian corridors, with the consequent drastic contraction or even disappearance of both species in the Mediterranean Basin.

Providing insights into browntail moth local outbreaks by combining life table data and semi-parametric statistics

1. Life table studies have been an essential tool for the comprehension of insect population dynamics, although their use has been methodologically biased by a primary focus on mortality factors, especially natural enemies. Thus, studies in natural populations may relegate important mortality sources to the ‘unknown’ or ‘residual’ mortality categories. To overcome this limitation, life tables may be complemented by combining them with other approaches.

Small sweat bees (Hymenoptera: Halictidae) as potential major pollinators of melon (Cucumis melo) in the Mediterranean

In the current scenario of a general decline of the honeybee worldwide, studies on the potential of alternative bee species in pollinating cultivated plants are important. Although melon, Cucumis melo, is a crop with great commercial importance, there is very little information on its pollinating fauna in Europe, and none from the southern Mediterranean area. In a locality in central Spain, using both pan‐traps and net collections, we found that melon flowers are visited by 31 species of bees spanning four families, though only four were both dominant and constant. These four species belonged to the family Halictidae (sweat bees) and mostly (three species) to the genus Lasioglossum. Five other species could be defined as accessory: honeybee, Apis mellifera, and four other halictids. Individuals of the dominant species were smaller, on average, than those from all the other species. Observations on the frequency of pollen and nectar foraging and on flower visit duration further suggested L. malachurum as the potential key pollinator. Females of this species started to forage on melon early in the flowering season and exhibited two activity peaks in summer, thus covering the whole season. Although in other sites across continents melon seems to be more heavily pollinated by honeybees, this seems to be not the case in the Mediterranean, where sweat bees seem to be the major pollinators of this crop.

Lectotypification of Centaurea alpina L. (Compositae) and the identity of Centaurea linaresii Lázaro Ibiza

A lectotype for the name Centaurea alpina (≡ Rhaponticoides alpina, Compositae) is herein designated from original material conserved in the BM Herbarium (Clifford Herbarium). A previously accepted name, Centaurea linaresii, is treated as a synonym; this name was previously typified from original material conserved in the MAF Herbarium, but was wrongly considered as holotype. Thereafter, it is here corrected to lectotype. This is an Accepted Manuscript of an article published in Taxon on June 2014, available online: http://dx.doi.org/10.12705/633.3

A NEW SPECIES OF TELENOMUS HALIDAY (HYMENOPTERA: SCELIONIDAE) ASSOCIATED WITH EGG BATCHES OF THE PINE PROCESSIONARY MOTH, THAUMETOPOEA PITYOCAMPA (DENNIS ET SCHIFFERMÜLLER, 1775) (LEPIDOPTERA: NOTODONTIDAE), FROM PENINSULAR SPAIN'

ABSTRACT: Telenomus thaumetopoeae Buhl sp. n. is described from northeastern València (Peninsular Spain) taking as starting point females parasitizing the egg-batches of the Pine Processionary Moth, Thaumetopoea pityocampa (Dennis et Schiffermüller, 1775). Its morphological affinities with the most closely related species and parasitism data are offered.