Metapochonia hahajimaensis (Clavicipitaceae,Hypocreales), a new species from soil in Hahajima Island,Tokyo, Japan

A new species, Metapochonia hahajimaensis is proposed. Three isolates were obtained from soil samples collected from Hahajima, Ogasawara Islands, Tokyo, Japan. Using a combination of morphological characteristics and multigene (ITS, SSU, LSU, TEF) phylogenics, the isolates were identified as a Metapochonia species which were previously undescribed. The new species is distinguished from the closely-related M. bulbillosa and M. goniodes or other Metapochonia taxa by conidial size and colonial characteristics.     

Multiple chromosomal inversions contribute to adaptive divergence of a dune sunflower ecotype

Both models and case studies suggest that chromosomal inversions can facilitate adaptation and speciation in the presence of gene flow by suppressing recombination between locally adapted alleles. Until recently, however, it has been laborious and time‐consuming to identify and genotype inversions in natural populations. Here we apply RAD sequencing data and newly developed population genomic approaches to identify putative inversions that differentiate a sand dune ecotype of the prairie sunflower (Helianthus petiolaris) from populations found on the adjacent sand sheet. We detected seven large genomic regions that exhibit a different population structure than the rest of the genome and that vary in frequency between dune and nondune populations. These regions also show high linkage disequilibrium and high heterozygosity between, but not within, arrangements, consistent with the behaviour of large inversions, an inference subsequently validated in part by comparative genetic mapping. Genome–environment association analyses show that key environmental variables, including vegetation cover and soil nitrogen, are significantly associated with inversions. The inversions colocate with previously described “islands of differentiation,” and appear to play an important role in adaptive divergence and incipient speciation within H. petiolaris.     

Enquêtes sur l'archipel de la Maddalena (Sardaigne NE): la flore et le paysage végétal de l'[icaron]le des Bisce

Abstract

Presented herevin are the results of research on the flora and vegetable landscape of the isola delle Bisce (NE Sardinia). The flora was found to be composed of 230 entities (1 Gymnospermae, 229 Angiospermae) belonging to 47 families and included in 156 genera. Failure to find numerous species is underscored and an overview of the vegetation landscape based on aerial photography is presented, with the identification of the vegetation formations and sites on the islands most sensitive to anthropic impact.     

Stipa valdemonensis (Poaceae), a new species from Sicily

Abstract

A new species of Stipa, endemic to Sicily, named Stipa valdemonensis is described here. The new taxon is related to Stipa crassiculmis. Owing to the small number of individuals observed, in few restricted localities only, it is assigned the IUCN threat status “vulnerable”.     

Balearic insular isolation and large continental spread framed the phylogeography of the western Mediterranean Cheirolophus intybaceus s.l. (Asteraceae)

Recent Quaternary geological and climate events have shaped the evolutionary histories of plant species in the Mediterranean basin, one of the most important hotspots of biodiversity. Genetic analyses of the western Mediterranean Cheirolophus intybaceus s.l. (Asteraceae) based on AFLP were conducted to establish the relationships between its close species and populations, to reconstruct the phylogeography of the group and to analyse potential unidirectional versus bidirectional dispersals between the Ibero‐Provençal belt and the Balearic Islands. AFLP data revealed two main genetic groups, one constituted by the Balearic populations and Garraf (NE Iberia) and the other formed by the remaining mainland populations that were further sub‐structured into two geographically separated subgroups (SE + E Iberia and NE Iberia + SW France). Genetic diversity and spatial structure analyses suggested a mid‐Pleistocene scenario for the origin of C. intybaceus in southern Iberia, followed by dispersal to the north and a single colonisation event of the Balearic archipelago from the near Dianic NE Iberian area. This hypothesis was supported by paleogeographic data, which showed the existence of terrestrial connections between the continent and the islands during the Middle–Late Pleistocene marine regressions, whereas the more recent single back‐colonisation of the mainland from Mallorca might be explained by several hypotheses, such as long‐distance dispersal mediated by migratory marine birds or sea currents.     

Length-weight relationship of twelve mesopelagic fishes from the western Tropical Atlantic

Length-weight relationship parameters were calculated for twelve mesopelagic fish species from the western Tropical Atlantic: Diretmus argenteus, Melamphaes polylepis, Bolinichthys distofax, Diaphus lucidus, Diaphus splendidus, Electrona risso, Hygophum taaningi, Taaningichthys bathyphilus, Melanolagus bericoides, Winteria telescopa, Diplophos taenia, Astronesthes similus. Data was collected off northeastern Brazil from April 9th to May 6th, 2017. Hauls were conducted during day and night at 47 stations by using a micronekton trawl (body mesh: 40 mm, cod-end mesh: 10 mm) from 10 to 1,113 m depth. The material was fixed in a 4% formalin solution for 1 month and then preserved in a 70% alcohol solution for proximally 6 months before processing for length (nearest 0.1 cm of standard length) and weight (nearest 0.01 g of total weight). A new maximum standard length for Winteria telescopa is also provided.     

The population ecology of Rattus exulans on Tiritiri Matangi Island,and a model of comparative population dynamics in New Zealand

Abstract

On Tiritiri, a small predator-free island in northern New Zealand, kiore (Rattus exulans) were live and snap trapped in grassland and forest. In both habitats, kiore abundance peaked in late summer/autumn. The increase followed a 3 month breeding season during which females produced two to three litters, each averaging 7 young. During the population decline in autumn and winter, animals lost weight. Few bred in the breeding season of their birth and none lived to breed in a second breeding season, so the population consisted of distinct age cohorts. These patterns may relate to a highly seasonal food supply.

Kiore elsewhere in New Zealand show seasonal breeding, but the length of breeding, sexual maturation, and litter size vary. Other studies of kiore in the Pacific show less marked seasonal fluctuations, longer breeding seasons, and smaller litters. We propose a model to explain the variation in rodent demography in New Zealand. The model is based on the seasonal availability of food, along with the modifying influences of predation and dispersal.     

Palynological and chemical volatile components of typically autumnal honeys of the western Mediterranean

Measurements and observations of pollen grains of varying structure before and after dehiscence of the anther sac illustrate large magnitudes of harmomegathic changes in volume and shape. Such changes are compared for colpate, porate, and colporate grains, and it is suggested that the nature of the harmomegathal action may serve to distinguish colpi or furrows from pores. Consideration of the requirement to allow harmomegathy while preventing wall collapse may provide at least partial explanation for evolution of the internal structure and external sculpturing of pollen grain walls.