Type specimens in the Vidal Herbarium at the Real Jardín Botánico,Madrid

Ninety eight type specimens collected by Sebastián Vidal in the Philippines, and kept at the Real Jardín Botánico Herbarium, Madrid (MA), are compiled. Most of these specimens are types of Vidal's names. Only a few are names of other authors (Hoogland, Merrill, and Rolfe). A list of specimens, as well as the indicatio locotypica and number in MA, is presented. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 292–299.     

Plant patch structure modifies parasitoid assemblage richness of a specialist herbivore

1. The spatial structure of plant patches has been shown to affect host–parasitoid interactions, but its influence on parasitoid diversity remains largely ignored. Here we tested the prediction that parasitoid species richness of the specialist leafminer Liriomyza commelinae increases in larger and less isolated patches of its host plant Commelina erecta. We also explored whether parasitoid abundance and body size affected the occurrence of parasitoid species in local assemblages. 2. A total of 893 naturally established C. erecta patches were sampled on 18 sites around Córdoba city (Argentina). Also, two experiments were performed by creating patches differing in the number of plants and the distance from a parasitoid source. For these tests, plants were infected with the miner in the laboratory prior to placement in the field. 3. Plant patch size, independently of host abundance, positively affected the number of parasitoid species in both survey observations and experimental data. However, plant patch isolation did not influence parasitoid species richness. 4. The probability of finding rare parasitoid species increased with patch size, whereas occupation of isolated patches was independent of dispersal abilities (body size) of parasitoid species. 5. Overall, the results highlight the importance of considering spatial aspects such as the size of plant patches in the study of parasitoid communities.     

Pattern of differentiation in the annual killifish genus Austrolebias (Cyprinodontiformes: Rivulidae) from a biosphere reserve site in South America: a multidisciplinary approach

The annual killifish genus Austrolebias includes approximately 38 species distributed throughout the Paraná-Plata basin and Patos-Merín system. Within the Austrolebias adloffi species complex, the Uruguayan populations of Austrolebias charrua were considered as an intergradation between A. adloffi and Austrolebias viarius populations. Austrolebias charrua presents an intermediate phenotype between both taxa and high levels of morphological and chromatic variability. In the present study, we incorporate different methodological approaches (molecular, morphology, and gamete ultrastructure) to elucidate the pattern of differentiation among the parapatric taxa ( A. charrua , Austrolebias reicherti , A. viarius ) distributed in a Biosphere Reserve Site. Analyses of cytochrome b sequences show high values of DNA polymorphism, in particular for A. charrua. This is in accordance with both morphological and gametic variation. Using a statistical parsimony network based on these sequences and analysis of morphological data, past fragmentation and range expansion involving perhaps secondary contact between A. charrua and A. reicherti could be proposed. Coloration pattern and morphometric analyses showed an unexpected higher similarity between the most distantly-related taxa, A. viarius and A. charrua . This could be the result of retention of ancestral polymorphisms, especially in A. charrua populations from ponds of higher elevation, or to directional selection acting in similar ecological environments. Because these annual killifish species are considered endangered, our work reinforces the high priority need to include them in a conservation programme.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 620–635.     

Ontogenetic variation in density‐dependent growth of brown trout through habitat competition

1. Density‐dependent growth has been widely reported in freshwater fishes, but the ontogenetic evolution of competition and its subsequent effects on growth through a life span remains unclear. 2. Patterns of competition can be described by integrating population abundance data with habitat‐modelling results. Weighted usable area (WUA; m² WUA ha^?1) curves are obtained for each flow value and are then coupled with demographic data to obtain the occupancy rates (trout m^?2 WUA, the density of a given age class related to its suitable habitat) of the WUA for every age class, year and site. 3. We examined a long‐term data series searching for temporal variation in the influence of habitat occupancy rate on the growth of brown trout Salmo trutta. We tested whether (i) mean cohort mass (mean mass of the cohort during the first 3 years of life) is affected by the occupancy rate experienced across a life span; and (ii) the occupancy rate experienced at different ages influenced mean body size. 4. We observed a consistent negative power relationship between average cohort mass and mean occupancy rate through a life span, indicating that stronger cohorts were related to a reduced growth, with likely consequences for individual fitness. 5. The effects of occupancy rate on size‐at‐age were mainly detected in the size attained at the second year of life, but they were because of the competition at different times. Thus, the level of competition varied through ontogeny, in some of the rivers affecting growth since the first year of life, whereas in most of the rivers the main effects on body size resulted from the competition during the second year of life. 6. Occupancy rate appears more appropriate than density for assessing the occurrence of habitat competition in freshwater fishes, since it encompasses the differences in quantity and quality of suitable habitat for each age class. 7. Our study highlights the importance of density‐dependent growth as a key process in the dynamics of brown trout populations, its temporal variation depending on the temporal changes of density and the variation of competition associated with the habitat capacity for each life stage.     

A NEW TEMNOSPONDYL FROM THE PERMO-TRIASSIC BUENA VISTA FORMATION OF URUGUAY

Abstract:  A partial skull recovered from conglomerates of the Permo-Triassic Buena Vista Formation in Uruguay belongs to a new species, Uruyiella liminea gen. et sp. nov. This species is characterized by a broadly triangular skull with laterally projecting posterior corners, rhytidosteid-like dermal sculpturing, and orbits positioned close to the skull margin. Uruyiella liminea is distinguished from other temnospondyls by a combination of primitive and derived character states, such as the anterior extent of the palatine ramus of the pterygoid, which excludes the ectopterygoid and most of the palatine from the lateral border of the interpterygoid vacuity, and the absence of both tabular horns and otic notches. A phylogenetic analysis places Uruyiella and the enigmatic Early Triassic Laidleria in a clade to which we attach the family name Laidleriidae. The Plagiosauridae and the Laidleriidae form a clade at the base of Dvinosauria, which is the sister group of a clade that includes Stereospondyli and Archegosauroidea. This result is unexpected because Laidleria and Plagiosauridae are nested deeply within Stereospondyli in most phylogenies. The sister-group relationship of Uruyiella and Laidleria suggests that a ghost lineage for the latter genus extends down into the earliest Triassic and perhaps even into the Late Permian, which in turn would suggest survivorship of the Laidleriidae through the Permo-Triassic extinction event.     

Foraging conditions ‘at the end of the world’ in the context of long‐distance migration and population declines in red knots

The long‐distance migrant red knot (Calidris canutus ssp. rufa– Scolopacidae) alternates between the northern and southern ends of the New World, one of the longest yearly migrations of any bird and paradoxically overflying apparently suitable habitat at lower latitudes. This subspecies is sharply declining, with a major mortality event following 2000, attributed to commercial overharvesting of food resources at its Delaware Bay (USA) stop‐over site. A full understanding of this peculiar migrant requires an assessment of the foraging conditions at its southern hemisphere wintering sites. Here, for a major wintering site in Argentinean Tierra del Fuego (Río Grande), we describe and compare food abundance, diet and intake rates during January–February in 1995, 2000 and 2008. The two main prey types were the burrowing clam Darina solenoides and three species of epibenthic mussels Mytilidae. In the year 2000, food availability and intake rate were higher than those recorded at other sites used by knots anywhere else in the world, contributing to the explanation of why red knots carry out this impressive migration. Intake rate in 2008 on the two main prey types was dramatically reduced as a result of birds eating smaller prey and strongly increased human disturbance; the same year we also found a high prevalence of a digenean parasite in Darina. We suggest that during the strongly enhanced winter mortality in 2000, knots did not yet face ecological problems in their southernmost wintering area, consistent with the previous evidence that problems at northern stop‐overs negatively affected their numbers. However, in 2008 the ecological conditions at Río Grande were such that they would have facilitated a further decline, emphasizing the importance of a hemispheric approach to research and management.     

Isolation and characterization of microsatellite markers in Calomys musculinus (Muridae,Sigmodontinae, Phyllotini), the natural reservoir of Junin virus

Calomys musculinus, one of the most abundant rodent species in central Argentina, is the reservoir of Junin virus, the aetiological agent of Argentine hemorrhagic fever. We isolated six polymorphic microsatellite loci for microgeographical studies of population structure in this species. Amplification of these loci in 36 individuals from three natural populations revealed five to 14 alleles per locus and expected heterozygosities from 0.426 to 0.868. Cross‐species amplifications suggest that primers designed for these loci may be useful in other closely related species of the tribe Phyllotini, but not in species of other more distantly related tribes of the subfamily Sigmodontinae.