Strengthening the Natural and National Park system of Iberia to conserve vascular plants

The diversity of the Iberian vascular flora has been investigated using WORLDMAP versions 3.08 and 3.18. Two data sets scoring plant distributions as presences within the Iberian Peninsula were compiled; one for 2133 species at 50 × 50 km grid and the other for 801 species at 10 × 10 km map grids. Patterns of biodiversity were determined using the diversity measures of species richness, range-size rarity and character richness diversity. Using the diversity measures, combined with an area selection method, maps of priority areas were calculated using iterative procedures. Near minimum sets (NMSs) for both scales were calculated. Comparison of the NMS for the 10 × 10 km grid with the near minimum set for existing reserves (NMSER) showed that at least 2% more of the land surface would be required above and beyond the existing protected area network, currently comprising 6% of the area, to ensure representation of all species at least once as listed within the present data-base. It is demonstrated that reserve systems selected on a variety of different criteria are suboptimal when compared to particular groups of target organisms with a definite goal of representation for conservation. Calculating efficiency of existing reserve systems and accounting for all taxa identifies precisely the extra required areas for the protected area system to satisfy particular goals of representation.     

Predispersal reproductive biology of female Osyris quadripartita (Santalaceae), a hemiparasitic dioecious shrub of Mediterranean scrublands

Female Osyris quadripartita plants exhibit uninterrupted reproductive activity throughout the year, due to the long duration of successive stages in the cycle and marked within-crop developmental asynchrony. Cycles corresponding to the flowering seasons of consecutive years overlap in each individual. Flowering takes place in spring, and fruits develop in the dry summer season and ripen at any time of the year. Variation in flowering time explains a negligible proportion of variation in ripening time. The greatest reproductive losses are incurred in the phase extending from closed flowers through unripe fruits, mostly due to ovary abortion. Only 30% of closed flowers eventually reach this latter stage. In contrast, 75% of unripe fruits complete their development, with subsequent dispersal of seeds. The probability of the setting of ripe fruit steadily decreases from early to late season flowers, due to increased ovary abortion rates. Resource limitation in the dry summer season seems responsible for this pattern of selective fruit maturation.     

Preliminary assessment of the use of electron backscatter diffraction (EBSD) in conodonts

Pérez‐Huerta, A., Cusack, M. & Méndez, C.A. 2011: Preliminary assessment of the use of electron backscatter diffraction (EBSD) in conodonts. Lethaia, Vol. 45, pp. 253–258. Conodonts are extensively used as ‘geochemical tools’ in palaeoenvironmental reconstructions in Palaeozoic and Triassic strata. The retention of a primary geochemical signal is substantially dependent on the ultrastructural integrity and crystallinity after diagenesis. Direct assessments of the preservation potential of the polycrystalline matrix are scarce with the exception of the application of transmission electron microscopy (TEM). The possible application of electron backscatter diffraction (EBSD) is introduced for well‐preserved Pennsylvanian platform conodont elements as a novel in situ technique based on successful previous results for biogenic carbonates. EBSD shows the presence of no diffraction in central regions of all studied elements of Idiognathodus and Adetognathus, with possible implications for geochemistry analysis. The absence of diffraction could be attributed to the existence of an amorphous phase, water (+OH) or a process of hypocalcification related to the development of ‘growth cavities’ in the lamellar crown tissue. Overall results indicate the suitability of using EBSD to extract crystallographic information from conodonts and potentially for other apatite (micro‐) fossils. □Conodont, diagenesis, EBSD, geochemistry, Pennsylvanian.     

Purine Metabolism in Trypanosomatids*

SYNOPSIS. Purine nucleotide biosynthesis was studied in culture forms of Trypanosoma cruzi strain Y, Crithidia deanei (a reduviid trypanosomatid with an endosymbiote) and an aposymbiotic strain of C. deanei (obtained by curing C. deanei with chloramphenicol). Trypanosoma cruzi was found to synthesize purine nucleotides only from the preformed bases adenine and guanine (“salvage” pathway), adenine being incorporated into both adenine and guanine nucleotides. Similar results were obtained with guanine, indicating that this flagellate has a system for the interconversion of purine nucleotides. Crithidia deanei was able to synthesize purine and pyrimidine nucleotides from glycine (“de novo” pathway) and purine nucleotides from adenine and guanine (“salvage” pathway). Adenine was incorporated into both adenine and guanine nucleotides, while guanine was incorporated into guanine nucleotides only, indicating the presence of a metabolic block at the level of GMP reducaase. The aposymbiotic C. deanei strain was unable to utilize glycine for the synthesis of purine nucleotides, although glycine was utilized for synthesizing pyrimidine nucleotides. These results suggest that the endosymbiote is implicated in the de novo purine nucleotide pathway of the C. deanei-endosymbiote complex. The incorporation of adenine and guanine by aposymbiotic C. deanei strain followed a pattern similar to that observed for C. deanei.     

Atypical Androgen Receptor in the Human Melanoma Cell Line IIB-MEL-J

To evaluate the presence of androgen receptors in the human melanoma cell line IIBMEL-J, a Scatchard plot analysis was performed. Cells in culture revealed a single binding component with an apparent dissociation constant (K_D) at 37°C of 11 nM and a binding capacity of 326 fmol/mg protein when measured with [³H]-R1881. Competition analysis revealed an atypical relaxation of specificity, since not only androgen (testosterone, dihydrotestosterone [DHT], R1881) and antiandrogen (hydroxy-flutamide [OH-FLU]) competed for [3H]-R1881 binding, but also estradiol, progesterone, and cortisol at 500-fold excess concentration. Binding of [3H]-estradiol and [3H]-R5020 in the absence of unlabeled DHT were completely suppressed in its presence. Immunohistochemistry of androgen receptor with a monoclonal antibody showed that nuclei were vigorously stained. Different doses of flutamide (FLU) and OH-FLU tested on cultured IIB-MEL-J cells in the presence of serum inhibited significantly cell proliferation in a dose-dependent manner. When cells were incubated with 10 nM DHT and 1%charcoal-adsorbed serum, a significant stimulation of growth that was observed was inhibited by 4 μM OH-FLU. DHT stimulation was completely reversed by the antiestrogen tamoxifen. In addition, male nude mice transplanted with IIB-MEL-J tumor were treated with FLU when tumors were palpable. FLU was effective in diminishing tumor growth and increasing survival rate of the animals. As a conclusion, the presence of functional androgen receptors in these cells has been demonstrated by growth inhibition in vitro and in vivo with antiandrogens, and their atypical nature is suggested by binding cross-reactivity and competition studies.     

Molecules,ecology, morphology,and songs in concert: how many species is Arremon torquatus (Aves: Emberizidae)?

The acceptance of the generalized or unified concept of species (i.e. that species are segments of population lineages) implies that an important task for systematists is to focus on identifying lineages and on testing hypotheses about the acquisition of properties such as phenotypic diagnosability, reciprocal monophyly, or mechanisms of reproductive isolation. However, delimiting species objectively remains one of the most challenging problems faced by biologists. In the present study, we begin to tackle the thorny issue of species delimitation in a complicated group of Neotropical passerine birds (the Arremon torquatus complex, Emberizidae) in which sets of characters vary substantially across space, but do not obviously vary in a concerted fashion. To earlier discussions of species limits in the group, we add a historical perspective offered by a recent molecular phylogeny, present quantitative analyses of morphological and vocal variation, and incorporate ecological niche models as a new tool that aids species delimitation by highlighting cases of ecological distinctiveness and cases where populations appear to be in independent evolutionary trajectories, despite being connected by environments unlikely to represent barriers to gene flow. We demonstrate that at least one pair of taxa (and likely another) currently treated as conspecific are, in fact, distinct lineages that merit species status under essentially any species criterion. However, other pairwise comparisons are not as straightforward owing to nonconcordant patterns of variation in different traits and to the impossibility of distinguishing which characters are causes and which are consequences of reproductive (and evolutionary) isolation. After considering several alternatives, we propose a provisional classification of the complex recognizing eight tentative species‐level taxa. Although this classification is likely to change as more detailed work is conducted, it provides a better foundation for studying the biology of these birds and helps to better describe their diversity, which is obscured when all taxa are subsumed into a single species name. The present study highlights several outstanding challenges, both practical and conceptual, for future studies. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 152–176.     

Seasonality and life cycles of woody plant-feeding noctuid moths (Lepidoptera: Noctuidae) in Mediterranean habitats

Abstract.

• 1 The annual cycle of noctuid moths feeding as larvae on the foliage of eighteen woody plant species (belonging to ten different families) was studied at two southeastern Spanish Mediterranean forest habitats. Two questions were addressed in this study. (1) Does the rigorous (hot and dry) summer season characteristic of the Mediterranean-type climate impose a constraint on noctuid life histories? (2) Are there detectable differences in abundance or phenological patterns between the noctuid assemblages feeding on evergreen and winter-deciduous trees and shrubs?
• 2 Regardless of their leaf persistence habit, the majority of woody species studied had short shoot growth and leaf production periods in spring. Abundance of noctuid larvae peaked in May-June, shortly after host plants started to produce new leaves. Virtually no noctuid larvae were found on the foliage of the woody species studied at other times of year. Abundance and seasonal pattern of occurrence of larvae were similar on evergreen and deciduous food plants.
• 3 In contrast with the unimodal seasonal pattern exhibited by larvae, the abundance of adult moths (assessed by light trapping) showed two distinct peaks in early summer and early autumn, and a marked minimum in mid-summer.
• 4 Most woody plant-feeding noctuids recorded in this study (86% of species, about 95% of individuals) were univoltine. Univoltine species fell into one of two distinct life history categories, corresponding to pre- and post-summer flight periods. These two contrasting phenologies were associated with a bimodality in the duration of the pupal stage (‘short’ versus ‘long’), and were closely related to taxonomical affiliation at the subfamily level.
• 5 Within the ‘short’ pupal duration group, some species mate and oviposit shortly after emergence and pass the dry season in the egg stage, while others remain as potentially active, non-reproductive adults over most of the summer and mate by the end of that season. Species in the ‘long’ pupal duration group pass the summer in pupal or prepupal stage.
• 6 In the Mediterranean habitats studied, the adversity of the summer dry season seems to have led to a woody plant-feeding noctuid species assemblage almost entirely made up of univoltine species that concentrate their larval phases when suitable food (young leaves) is most abundant, and ‘avoid’ mid-summer as a flight time by emerging either shortly before or shortly after the adverse summer drought period. Year-round foliage availability afforded by dominant evergreen plants does not seem to have influenced the seasonal organization of noctuid cycles in any substantial way.