Hygrophorus sect. Olivaceoumbrini: new boundaries, extended biogeography and unexpected diversity unravelled by transatlantic studies

As currently delineated, Hygrophorus sect. Olivaceoumbrini is a polyphyletic assembly within subg. Colorati, encompassing glutinous and pigmented taxa. According to available literature, between a dozen and twenty species may belong in the section, mostly represented in continental and boreal forests of Europe and North America. However, the limited phylogenetic and biogeographic coverage of the genus does not presently allow for a reliable assessment of its taxonomic boundaries, nor does it provide a complete picture of species diversity within sect. Olivaceoumbrini. In an ongoing effort to confer an evolutionary backbone to Hygrophorus systematics, we assembled and analysed a dataset comprising 268 intercontinental sequences, including holotypes of 7 taxa previously not positioned phylogenetically, and enriched with collections from largely unexplored Mediterranean and Anatolian ecosystems. Overall, 30 clades are identified within 5 distinct lineages, including 11 species putatively new to science. Seven of these are formally described here as H. agathosmoides, H. albofloccosus, H. canadensis, H. limosus, H. marcocontui, H. pinophilus and H. pustulatoides spp. nov. This enriched coverage of section Olivaceoumbrini s.lat. calls for a re-evaluation of its natural boundaries into a core monophyletic clade, including H. olivaceoalbus and five closely related lookalikes, as well as the assignment of the section rank to the four remaining lineages: sect. Fuscocinerei sect. nov., sect. Limacini sect. nov., sect. Nudolidi sect. nov. and sect. Tephroleuci, respectively. We also stabilize the usage of six historical names, H. glutinifer, H. hyacinthinus, H. mesotephrus, H. olivaceoalbus, H. pustulatus and H. tephroleucus, through designation of two neotypes, three lectotypes and four epitypes.

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Diversification of tree stands as a means to manage pests and diseases in boreal forests: myth or reality?

Canadian Journal of Forest Research ◽

10.1139/x05-172 ◽

2006 ◽

Vol 36 (2) ◽

pp. 324-336 ◽

Cited By ~ 59

Author(s):

Julia Koricheva ◽

Harri Vehviläinen ◽

Janne Riihimäki ◽

Kai Ruohomäki ◽

Pekka Kaitaniemi ◽

...

Keyword(s):

Species Diversity ◽

Tree Species ◽

Boreal Forests ◽

Tree Mortality ◽

Tree Species Diversity ◽

Mixed Stands ◽

Tree Species Composition ◽

Pests And Diseases ◽

Pest Outbreaks ◽

Disease Epidemics

Pure forest stands are widely believed to be more prone to pest outbreaks and disease epidemics than mixed stands, leading to recommendations of using stand diversification as a means of controlling forest pests and pathogens. We review the existing evidence concerning the effects of stand tree-species diversity on pests and pathogens in forests of the boreal zone. Experimental data from published studies provide no overall support for the hypothesis that diversification of tree stands can prevent pest outbreaks and disease epidemics. Although beneficial effects of tree-species diversity on stand vulnerability are observed in some cases, in terms of reductions in damage, these effects are not consistent over time and space and seem to depend more on tree-species composition than on tree-species diversity per se. In addition, while mixed stands may reduce the densities of some specialized herbivores, they may be more attractive to generalist herbivores. Given that generalist mammalian herbivores cause considerable tree mortality during the early stages of stand establishment in boreal forests, the net effect of stand diversification on stand damage is unlikely to be positive.

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Bias in the published fossil record

Paleobiology ◽

10.1017/s0094837300006060 ◽

1978 ◽

Vol 4 (3) ◽

pp. 367-372 ◽

Cited By ~ 46

Author(s):

Carl F. Koch

Keyword(s):

Species Diversity ◽

North America ◽

Normal Distribution ◽

Fossil Record ◽

Geologic Time ◽

Abundance Data ◽

Significant Bias ◽

Mollusc Species ◽

Log Normal ◽

Log Normal Distribution

The published fossil record has significant bias in favor of common and biostratigraphically important taxa when compared with data obtained from a thorough examination of several hundred collections from the Western Interior of North America. Overall species diversity is underestimated by a factor of 3 to 4, and bivalve and gastropod diversity by a factor of 5. The proportion of bivalves increased from 40 to 56% of the fauna, and the proportion of ammonites decreased from 28 to 18%. Thirteen published reports listed 65 species from 203 reported occurrences. Data from all sources showed 170 species for 1050 occurrences. By using abundance data and assuming a log-normal distribution, as many as 200 fossilizable mollusc species may have inhabited the Western Interior during the uppermost biozone of the Cenomanian. The importance of this study is that it quantifies the bias in the published fossil record relative to the potential fossil record for an unusually well studied interval of geologic time. The bias would be greater for less well studied strata.

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An annotated checklist of the psyllids of California (Hemiptera: Psylloidea)

Zootaxa ◽

10.11646/zootaxa.3193.1.1 ◽

2012 ◽

Vol 3193 (1) ◽

pp. 1 ◽

Cited By ~ 18

Author(s):

DIANA M. PERCY ◽

ALESSANDRA RUNG ◽

MARK S. HODDLE

Keyword(s):

Biological Control ◽

Species Diversity ◽

North America ◽

Key Words ◽

Pest Species ◽

Floristic Diversity ◽

Control Programs ◽

New Synonym ◽

Annotated Checklist ◽

Key Words Biogeography

A revised checklist to the species of Psylloidea (Hemiptera) from California is presented, with information on host plantdata, distributions, introduced and pest species, parasites, parasitoids, and predators, and biological control programs. Thelist includes 164 species, of which six are newly recorded. In total, this comprises a 26% increase in the number of speciesrecorded for California since the last published checklist in 1988. Choricymoza Bliven is a new synonym of PhylloplectaRiley, and 10 species previously in Euphalerus Schwarz are recombined under Nyctiphalerus Bliven. California has therichest native psyllid fauna in North America, and the influence of climatic and floristic diversity on this diversificationis considered. Key words: biogeography, host plant, jumping plant lice, species diversity, pest species.

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Species diversity in the Phanerozoic: a tabulation

Paleobiology ◽

10.1017/s0094837300004917 ◽

1976 ◽

Vol 2 (4) ◽

pp. 279-288 ◽

Cited By ~ 115

Author(s):

David M. Raup

Keyword(s):

Species Diversity ◽

North America ◽

Absolute Time ◽

Invertebrate Species ◽

Time Diversity

On the basis of about 70,000 species citations in the Zoological Record, it is estimated that about 190,000 fossil invertebrate species were described and named through 1970. The true figure may be higher because of incompleteness of the Zoological Record or lower because the estimate does not account for synonymy.About 70% of the species were described from USSR, Europe, and North America. About 42% are Paleozoic, 28% Mesozoic, and 30% Cenozoic. In the Cambrian part of the sample, 75% of the species are trilobites. In the Mesozoic and Cenozoic, about 70% are either molluscs or protozoans.When the data are normalized for absolute time, diversity (species per million years) shows a Paleozoic high in the Devonian which is approximately four-tenths of the Cenozoic level.

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Long-term succession of closed boreal forests at their range limit in eastern North America shows resilience to fire and climate disturbances

Forest Ecology and Management ◽

10.1016/j.foreco.2019.03.015 ◽

2019 ◽

Vol 440 ◽

pp. 101-112 ◽

Cited By ~ 1

Author(s):

Serge Payette ◽

Mathieu Frégeau

Keyword(s):

North America ◽

Boreal Forests ◽

Eastern North America ◽

Range Limit

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Influence of Site and Stand Factors on the Distribution of Crustose Lichens Of The Caliciales in a Suboceanic Spruce Forest Area in Central Norway

The Lichenologist ◽

10.1006/lich.1996.0029 ◽

1996 ◽

Vol 28 (4) ◽

pp. 315-330 ◽

Cited By ~ 19

Author(s):

Håkon Holien

Keyword(s):

Species Diversity ◽

Boreal Forests ◽

Detrended Correspondence Analysis ◽

Stand Age ◽

Spruce Forest ◽

Humid Climate ◽

Forest Patches ◽

Young Forests ◽

Old Trees ◽

Crustose Lichens

AbstractThe distribution of crustose Caliciales has been surveyed in 100 spruce forest patches in Sør-Trøndelag, central Norway. Relationships between occurrence of the species and a number of site and stand variables were analysed by detrended correspondence analysis (DCA) and direct gradient analysis. Species diversity7 was significantly higher in old forests and in forests at higher altitudes compared to young forests and forests at lower altitudes. Old trees and snags are considered to be the most important structural components in old forests promoting species diversity of the Caliciales. Threatened or vulnerable species, such as Chaenotheca gracilliina, Cybebe gracilenta, Sclerophora coniophaea and S. peronella were confined to forest on rich soils showing no correlation with forest stand age. Chaenotheca brachypoda and C. trichialis were found to be the most typical old forest species among the Caliciales. Humidiphilous species are considered to be less affected by forestry in a humid climate. A change in forestry practice towards methods imitating the natural dynamic processes is considered necessary to maintain species diversity of the Caliciales in boreal forests.

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Cretaceous vegetational change: a biomal perspective

The Paleontological Society Special Publications ◽

10.1017/s2475262200008558 ◽

1992 ◽

Vol 6 ◽

pp. 295-295

Author(s):

Garland R. Upchurch

Keyword(s):

Species Diversity ◽

North America ◽

Late Cretaceous ◽

High Latitude ◽

Deciduous Forest ◽

Terrestrial Ecosystems ◽

High Latitudes ◽

Coastal Regions ◽

Show Evidence ◽

Angiosperm Pollen

The Cretaceous rise of flowering plants marked an important transition in the modernization of terrestrial ecosystems. Well documented is the diversification of angiosperm pollen during the mid-Cretaceous and the migration of angiosperms from low latitudes to middle and high latitudes during the Barremian to Cenomanian. Global compilations of “species” diversity indicate a rapid rise in angiosperm diversity during the Albian to Cenomanian. This rise parallels a decline in the species diversity of archaic pteridophytes and the gymnosperm orders Cycadales, Bennettitales, Ginkgoales, Czekanowskiales, and Caytoniales. Late Cretaceous floras show more gradual trends in species diversity than mid-Cretaceous floras.Megafloral reconstructions of vegetation and climate for North America and other continents indicate warm temperatures in coastal regions of middle to high latitudes. Cretaceous biomes, however, often cannot be compared closely with Recent biomes. During much of the Cretaceous, conifers and other gymnosperms shared dominance with angiosperms in tropical and subtropical vegetation, unlike the Recent. During the Late Cretaceous, tropical rainforest was areally restricted. The few known leaf megafloras from equatorial regions indicate subhumid, rather than rainforest, conditions. Desert and semi-desert were widespread at lower latitudes and are documented by the occurrence of evaporite minerals in China, Africa, Spain, Mexico, and South America. Mid-latitude vegetation consisted of open-canopy broadleaved and coniferous evergreen woodlands that existed under subhumid conditions and low seasonality. High-latitude vegetation of the Northern Hemisphere consisted of coniferous and broadleaved deciduous forest, rather than boreal forest and tundra. High-latitude vegetation from coastal regions of the Southern Hemisphere consisted of evergreen conifers and angiosperms. Rainforest conditions appear to have been largely restricted to polar latitudes.Data on relative abundance, though often incomplete, indicate that angiosperms became ecologically important in tropical to warm subtropical broadleaved evergreen forests and woodlands by the Cenomanian. However, their rise to dominance took longer in other biomes. Conifers formed an important component of many Late Cretaceous biomes, and the persistence of archaic gymnosperms was strongly influenced by climate. Deciduous Ginkgoales, Czekanowskiales, Bennettitales, and Caytoniales are rare to absent in Late Cretaceous megafloras from warm subtropical to tropical climates, but they persist in megafloras from cooler climates. Archaic conifers such as Frenelopsis occur in megafloras representing low-latitude desert and semi-desert, but they are generally absent in more humid assemblages. Within mid-latitude broadleaved and coniferous evergreen woodland from North America, conifers show evidence for co-dominance with angiosperms into the early Maastrichtian. However, this co-dominance appears to have ended by latest Maastrichtian, which implies that vegetational reorganization occurred during the last few million years of the Cretaceous in North America.

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