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Volatile organic compounds are secondary metabolites emitted by all organisms, especially by plants and microbes. Their role as aboveground signals has been established for decades. Recent evidence suggests that they might have a non-negligible role belowground and might be involved in root–root and root–microbial/pest interactions. Our aim here was to make a comprehensive review of belowground volatile diversity using a meta-analysis approach. At first we synthesized current literature knowledge on plant root volatiles and classified them in terms of chemical diversity. In a second step, relying on the mVOC database of microbial volatiles, we classified volatiles based on their emitters (bacteria vs. fungi) and their specific ecological niche (i.e., rhizosphere, soil). Our results highlight similarities and differences among root and microbial volatiles and also suggest that some might be niche specific. We further explored the possibility that volatiles might be involved in intra- and inter-specific root–root communication and discuss the ecological implications of such scenario. Overall this work synthesizes current knowledge on the belowground volatilome and the potential signaling role of its constituents. It also highlights that the total diversity of belowground volatiles might be orders of magnitude larger that the few hundreds of compounds described to date.
We herein present the first annotated anuran checklist for the Brazilian state of Amapá, eastern Amazonia, based on a thorough literature review. We recorded the occurrence of 111 species belonging to 13 anuran families distributed across 48 localities throughout Amapá, within two biomes. Among these species, 62.5% occur exclusively in the Tropical Moist Broadleaf Forest biome, ~8% occur exclusively in the Tropical Savanna biome, and ~29% occur in both. Two species were considered endemic to Amapá and were registered only in the central portion of the state. Regarding the conservation status, only one species (Dendropsophus amicorum) is classified as threatened, assigned to the “critically endangered” category. The other species are categorized as either “least concern” or “data deficient” (85 and 8, respectively), whereas 21 are not evaluated. The current annotated list contributes to the incipient knowledge on anuran species richness in Amapá and, despite the research regarding anuran taxonomy has considerably progressed over the past 20 years, there is still much to do. Our data highlight the need for trained taxonomists to develop research in the state.
Im Koelerion glaucae-Vegetationskomplex der nördlichen Oberrheinebene konnten auf Arenosol-Standorten biologische Krusten identifiziert werden. Die basenreichen offenen Sande werden in den obersten Millimetern der Bodenschicht größerflächig mit Deckungen von 80 bis fast 90 % von diesen Krusten überzogen, wenn keine mechanischen Bodenstörungen auftreten. Es wurden bei der Analyse von 18 Krusten-Kleinflächen (je 5 x 5 cm) insgesamt 10 Taxa der Cyanobacteria, 9 Taxa der Chlorophyta/Chrysophyta, 3 Flechten- und 4 Moostaxa gefunden (mittlere Zahl der Taxa/Kleinfläche: 19,2), wobei vor allem Nostoc, Microcoleus, Oscillatoria, Zygogomum und Protonemata in den Proben dominant auftraten. Funktionelle Leistungen dieser Krusten hegen u. a. in der Festigung von Substrat und der Fixierung von Luftstickstoff (letzteres durch die im Gebiet dominant auftretenden Cyanobakterien). Da einige Gebiete seit 1999 mit Schafen beweidet werden, stellt sich die Frage, ob mechanische Störungen der Bodenoberfläche durch Tritt die Krusten zerstören und wenn, ob sie innerhalb eines Jahres regenerieren können. Um dies zu prüfen, wurde ein Experiment angelegt. Es war möglich, nach Anlage von systematisch verteilten 2 x 65 Flächen (je 20 x 20 cm) nicht nur den Faktor „künstliche“ mechanische Störung, sondern auch Störung durch Trittsiegel von Schaf und Esel zu untersuchen. Alle 65 Flächen wurden mit einer Grundaufnahme (Prozentskala) im August 2002 im Hinblick auf die makroskopisch sichtbaren Organismen und die Krustendeckung aufgenommen. Im Juli 2003 erfolgte dann die erneute Aufnahme nach im Herbst 2002 durchgeführter „künstlicher“ mechanischer Störung von 40 Flächen und Trittsiegel-Störung von 25 Flächen (13 Schaf, 12 Esel). Die Krusten regenerierten weder im Jahre 2003 noch bis Juli 2004. - Durch dieses Ergebnis entsteht eine ambivalente Situation: Auf der einen Seite ist ein Schutz der Krustendiversität vor den mechanischen Effekten der Weidetiere zumindest auf einigen Flächen notwendig. Auf der anderen Seite entstehen durch ein standortgemäßes Weidemanagement aus konsolidierten und oft ruderalisierten Rasen wiederum Koelerion glaucae-Fluren. Eine sehr extensive kurzzeitige Hütehaltung auf Teilen der Koelerion glaucae-Flächen wird empfohlen.
We report 106 species of caddisflies (Trichoptera) representing 44 genera and 16 families that were collected across 50 sampling sites in the Buffalo River watershed. The species collected represent about 45% of the known Interior Highlands caddisfly fauna. The most speciose families collected were the Hydroptilidae (30), Leptoceridae (21), and Hydropsychidae (17). Two species found during this study, Paduniella nearctica and Ochrotrichia contorta, are listed as species of special concern in the state of Arkansas due to their relative rarity. Similarity analysis values among collection sites ranged from 9% to 77%. Seriation analysis of caddisfly genera and species showed that most are distributed throughout the entire Buffalo National River but some are restricted to either the upper or lower river or its tributaries. This represents the first comprehensive survey of caddisflies completed for the Buffalo National River.
Capparis macrantha Souvannakhoummane, Fici & Lanorsavanh sp. nov., a new shrub species characterized by erect or ascending habit, stipular thorns, large lanceolate-elliptic leaves and large flowers in supra-axillary rows, is described and illustrated from the deciduous forest in Nam Kading National Protected Area (central Lao PDR). The new species belongs to Capparis sect. Monostichocalyx Radlk. and is morphologically similar to C. radula Gagnep., a shrub widespread in the Indochinese area, differing in the shorter, straight stipular thorns, larger leaves, larger sepals and petals, higher number of stamens with longer filaments and longer gynophore and ovary. Its affinities with related taxa are discussed and a key is provided for the species of Capparis L. known from Lao PDR. The conservation status of the new species is provisionally assessed as Vulnerable (VU D1).
The cattle egret (Bubulcus ibis) has recently colonized Brazil. This process offers an excellent opportunity for the study of colonization and dispersal patterns across extensive areas by non-native birds. The aims of the present investigation were a) to determine the genetic diversity of the cattle egret in Brazil and Africa, b) evaluate genetic differentiation between populations in different regions of Brazil and Africa, and c) detect genetic signs of demographic expansion in these two areas. Mitochondrial DNA (mtDNA) Control Region (CR) sequences were obtained from 112 cattle egrets in four Brazilian and four African (Kenya, Ghana and Nigeria) populations. Genetic diversity (H, h, θ) and population structure (AMOVA, Fst) were assessed and the populations were tested for signs of recent demographic expansion. A total of 35 haplotypes were found: 22 exclusive to Africa, 10 exclusive to Brazil and three shared by both samples. The degree of genetic diversity, determined by mtDNA analysis, was similar between Brazil and Africa, demonstrating that the successful colonization of the non-native area occurred with no significant loss of diversity. The pairwise Fst values among the Brazilian and African populations were all significantly different. The population in southern Brazilian exhibited the lowest degree of differentiation with respect to the African population, followed by the southeastern and northeastern populations of the country. The genetic differentiation data suggest that the colonization of Brazil by the cattle egret began in the southern region and expanded to the southeastern and northeastern regions of the country. This genetic differentiation pattern is in accordance with the higher number of cattle per grazing area in southern Brazil, which may have favored the onset of the successful establishment of the species. The findings indicate that mtDNA genetic diversity was retained during the colonization process and colonization began in the southern region of the country. Moreover, signs of demographic expansion were detected in the African sample.
During a taxonomic study of the species of Croton sect. Adenophylli occurring in Brazil, approximately 140 collections usually identified as Croton echioides, C. rhamnifolius or C. rhamnifolioides caught our attention due to the distinct morphology of vegetative and reproductive organs. After the analysis of these collections, we concluded that they represent a new species, C. sertanejus Sodré & M.J.Silva sp. nov., which was also corroborated by an anatomical study of their leaves. This new species can be differentiated by pseudomonopodial branching, leaves with petioles up to 1.7 cm long, 4–6 subsessile nectary glands and indumentum of sessile trichomes on both surfaces. Detailed descriptions, including details of leaf anatomy, are provided for C. sertanejus sp. nov. and C. echioides, its closely related species. We also formalize the synonymization of C. kalkmannii under C. echioides and re-evaluate the typification of these names, in order to better clarify their taxonomic status.
Cryptogams form a large part of dry grassland plant species richness. As a frequently used tool in grassland restoration, hay transfer is known to transfer cryptogam species. This might result in cryptogam stands differing from those achieved by natural succession. To assess hay transfer as a medium for cryptogam restoration, I analysed species composition of cryptogams in the hay of dry grasslands in Southern Germany, how fast they establish, and how fast they colonize adjacent plots. Cryptogam samples from hay showed species combinations similar to those of the mown sites and large shoot numbers to be present in the hay. Even low-growing and rare species were found in the hay. Hay receptor sites showed larger pleurocarpous moss and fruticose lichen patches than comparable sites without hay transfer, indicating earlier arrival of viable diaspores at the receptor sites. For acrocarpous mosses that colonize new sites by spores, no differences in turf size between succession and restoration plots were found. This shows that species transferred by hay have a distinct advantage over species that have to arrive at newly opened sites by natural means, i.e. many years later. The colonization from small restoration sites into adjacent areas without hay transfer proceeds with moderate speeds of about 1 to 2 m per year, probably with wind drift as the most important dispersal agent. Abundant cryptogam species including most pleurocarpous mosses and some Cladonia species rarely producing spores will be greatly enhanced by hay transfer. Nevertheless, the facilitation of pleurocarpous mosses may be detrimental to acrocarpous moss and epigaeic and saxicolous lichen species diversity, which should be considered in dry grassland restoration. I suggest a combination of different restoration measures in a mosaic pattern to create suitable conditions for a maximum of cryptogam species.
Conidera Rivalier, 1961 is a well-defined subgenus of tiger beetles (Coleoptera: Cicindelidae) hitherto only known from two species endemic to the island of Luzon. This paper describes the first species from Mindoro, with a doubtful record from Mindanao. Cylindera (Conidera) mindoroana Zettel and Wiesner, new species, differs strongly by an unusual shape of the female’s elytra. A diagnosis for Conidera and a key to the species of this subgenus is presented.
In this study we describe a new species of the click-beetle genus Lacon Laporte, 1838 from the relict Hyrcanian forest in northern Iran. Lacon mertliki sp. nov. is morphologically similar to L. lepidopterus (Panzer, 1801) but differs from the latter in the body coloration and pubescence, the shape of pronotum and scutellar shield, and male and female genitalia. We provide brief data on its ecology as well as an identification key to all Lacon species in Iran. Additionally, we synonymize Lacon nadaii Platia & Németh, 2011 with Lacon unicolor (Candèze, 1874).