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The role of systematics for understanding ecosystem functions: Proceedings of the Zoologica Scripta Symposium, Oslo, Norway, 25 August 2022
No full textConditions of emergence of the Sooty Bark Disease and aerobiology of Cryptostroma corticale in Europe
No full textThe sooty bark disease (SBD) is an emerging disease affecting sycamore maple trees (Acer pseudoplatanus) in Europe. Cryptostroma corticale, the causal agent, putatively native to eastern North America, can be also pathogenic for humans causing pneumonitis. It was first detected in 1945 in Europe, with markedly increasing reports since 2000. Pathogen development appears to be linked to heat waves and drought episodes. Here, we analyse the conditions of the SBD emergence in Europe based on a three-decadal time-series data set. We also assess the suitability of aerobiological samples using a species-specific quantitative PCR assay to inform the epidemiology of C. corticale, through a regional study in France comparing two-year aerobiological and epidemiological data, and a continental study including 12 air samplers from six countries (Czechia, France, Italy, Portugal, Sweden and Switzerland). We found that an accumulated water deficit in spring and summer lower than -132 mm correlates with SBD outbreaks. Our results suggest that C. corticale is an efficient airborne pathogen which can disperse its conidia as far as 310 km from the site of the closest disease outbreak. Aerobiology of C. corticale followed the SBD distribution in Europe. Pathogen detection was high in countries within the host native area and with longer disease presence, such as France, Switzerland and Czech Republic, and sporadic in Italy, where the pathogen was reported just once. The pathogen was absent in samples from Portugal and Sweden, where the disease has not been reported yet. We conclude that aerobiological surveillance can inform the spatial distribution of the SBD, and contribute to early detection in pathogen-free countries
Assessing the taxonomic status of the Gray Brocket Mazama simplicicornis argentina Lönnberg, 1919 (Artiodactyla: Cervidae)
No full textMazama simplicicornis argentina is the name that was given to describe a gray brocket collected by Lönberg in 1919 in the central Chaco region of Argentina. Subsequent authors, based on morphological similarities, considered this name to be a synonym for the species Subulo gouazoubira Fischer, 1814 from Paraguay. In the absence of genetic analyses to compare the Argentinian and Paraguayan gray brockets, we aimed to clarify the taxonomy of M. simplicicornis argentina through an integrative assessment using morphological, cytogenetical, and molecular data from its holotype and a current topotype. Qualitative skull features and cranio-morphometric results of M. simplicicornis argentina showed a great similarity with the S. gouazoubira neotype characters. The diploid chromosome number of M. simplicicornis argentinatopotype corresponded with the karyotypical pattern of S. gouazoubira with 2n = 70 and FN = 70, showing a great similarity in all classic and molecular cytogenetic results and revealing the homologies between karyotypes. The phylogenetic analysis of mitochondrial genes used in this study (concatenated partial ND5 and Cytb gene) allocated the M. simplicicornis argentina specimens in the monophyletic clade of S. gouazoubira with a branch value of 100%. These results show that there is no discontinuity between the Argentinian and Paraguayan gray brockets. Therefore, the individuals originally described as M. simplicicornis argentina should be recognized as S. gouazoubira
Saproxylic Hymenoptera in dead wood retained on clear cuts, relation to wood parameters and their degree of specialisation
No full textIntensive forestry is a threat to biodiversity, and therefore actions are made to mitigate this loss. The actions are, however, designed based on available knowledge about the requirements of species, and for saproxylic insects this concerns mainly Coleoptera, while the diverse but poorly known Hymenoptera has contributed less. In this paper we therefore asked whether the substrate requirements of Hymenoptera (divided as parasitoids and non-parasitoids) are similar to those of Coleoptera and Diptera. We used an insect material reared from logging residue wood for the comparison. Theoretically parasitoid Hyme- noptera should be less specialised than Coleoptera and other host species as they belong to a higher trophic level. However, we found no such difference and even an opposite trend, that parasitoids were more specialised than beetles. Parasitoids had significantly more species in newly dead wood of fine diameter (1–4 cm, compared to coarse wood of 8–15 cm) compared to other groups. This is probably due to that many of them have bark beetles as hosts. The non-parasitoids were less specialised than the other groups and more confined to old wood (4–5 years), which is in line with that many of them are aculeate wasps building nests in emergence holes from other insects. Implications for insect conservation The habitat requirements of Hymenoptera suggest that the conservation actions designed for the well known groups are also applicable for them. The parasitoids’ association to trivial substrates (fine wood) sug- gest a good supply of breeding habitat, whereas their high specialisation in combination with higher trophic level suggest they contain an even higher proportion of threatened species than Coleoptera. How this is traded off needs further studies
Redescription of Axine belones Abildgaard, 1794 (Monogenea, Axinidae), a gill parasite of Belone belone (Linnaeus, 1760) (Teleostei, Belonidae) off the Algerian coast, Western Mediterranean
No full textAxine belones Abildgaard, 1794 is a polyopisthocotylean monogenean, parasite of belonid fishes, and there are few accounts with morphological and morphometrical data. Here, we redescribe A. belones based on newly collected specimens from its type-host, the garfish Belone belone (Linnaeus, 1760) collected off Algeria, Western Mediterranean, a new locality for this species. Several anatomical and morphological features (genital apertures and clamps sclerites) are described and illustrated. We provide morpho-anatomical and morphometrical data, along with detailed illustrations of A. belones, and we discuss the host specificity of A. belones. Notes on hosts and localities of this species and other congeners are presented, and host specificity patterns of A. belones revealed stenoxenic specificity to Belonidae Bonaparte, 1835, whilst the genus Axine Abildgaard, 1794 seems to be restricted to fishes of the order Beloniformes. Our attempt to investigate morphometric variations between Mediterranean and oceanic specimens revealed that the two populations differed by the number of testes, body length, and clamp dimensions. However, the limited number of measured organs in the various accounts precluded any distinction between the populations. Molecular data for both Mediterranean and oceanic specimens are needed to determine the existence of cryptic species. Axine belones Abildgaard, 1794 je jednorodni metilj, nametnik na škrgama iglice, o kojem postoji malo radova s morfološkim i morfometrijskim podacima. U ovom radu dajemo ponovni opis vrste A. belones na temelju primjeraka sakupljenih na iglici Belone belone (Linnaeus, 1760), njegovog tipskog domaćina. Primjerci iglica su ulovljeni uz obale Alžira, u zapadnom Sredozemnom moru, što je ujedno i novi lokalitet za ovu vrstu nametnika. Opisano je i ilustrirano nekoliko anatomskih i morfoloških značajki (genitalni otvori i skleriti prijanjaljki). U radu se iznose morfo-anatomski i morfometrijski podatci, zajedno s detaljnim ilustracijama A. belones i raspravlja o specifičnosti domaćina A. belones. Prikazani su i zabilježeni domaćini i lokaliteti nalaza ove vrste i srodnika, a obrasci specifičnosti domaćina kod A. belones ukazali su na stenokseničnu specifičnost prema porodici Belonidae Bonaparte, 1835, dok je rod Axine Abildgaard, 1794 vjerojatno ograničen na ribe reda Beloniformes. Naš pokušaj da istražimo morfometrijske varijacije između sredozemnih i oceanskih jedinki otkrio je da se dvije populacije razlikuju po broju testisa, duljini tijela i dimenzijama prijanjaljki. Međutim, ograničeni broj izmjerenih organa u drugim literaturnim izvorima onemogućio je precizno utvrđivanje razlike između populacija. Postojanje kriptičnih vrsta bi se moglo dokazati korištenjem molekularnih metoda za sredozemne i oceanske uzork
Middle–Late Ordovician organic-walled phytoplankton from Sweden: diversity and early radiation
No full textThe Borenshult-1 core, drilled in the vicinity of Motala, east of Lake Vättern in south centralSweden, comprises a well-dated and nearly complete succession of marine marly carbonatesdeposited relatively close to land. The 34 core samples analyzed for palynology encompass theupper part of the Darriwilian (Furudal Limestone), the entire Sandbian (Dalby Limestone, theKinnekulle K-bentonite and the lower Skagen Limestone) and the lower part of the Katian (SkagenLimestone). The age of this interval is well-constrained to the late Darriwilian (Stage slice Dw3)–early Katian (Stage slice Ka1), based on conodonts and 206Pb/238U dating of volcanic ashdeposits
Analysis of fossil plant cuticles using vibrational spectroscopy: A new preparation protocol
No full textAnalyses for organic “fingerprints” on fossilized plant cuticles and pollen hold valuable chemotaxonomic and palaeoclimatic information, and are thus becoming more utilized by palaeobotanists. Plant cuticle and pollen composition are generally analyzed after standard treatments with several chemical reagents for mineral and mesophyll removal. However, the potential alterations on the fossil composition caused by the different cleaning reagents used are still poorly understood. We tested the effects of commonly used palaeobotanical processing methods on the spectra of fossilized cuticles from successions of Late Triassic to Early Jurassic age, including the gymnosperms Lepidopteris, Ginkgoites, Podozamites, Ptilozamites and Pterophyllum astartense. Our study shows that standard chemical processing caused chemical alterations that might lead to erroneous interpretation of the infrared (IR) spectra. The difference in pH caused by HCl induces changes in the proportion between the two bands at ~1720 and 1600 cm 1 (carboxylate and C-C stretch of aromatic compounds) indicating that the band at ~1610 cm 1 at least partially corresponds to carboxylate instead of C-C stretch of aromatic compounds. Interestingly, despite being used in high concentration, HF did not cause changes in the chemical composition of the cuticles. The most alarming changes were caused by the use of Schulze ’s solution, which resulted in the addition of both NO2 and (O)NO2 compounds in the cuticle. Consequently, a new protocol using H2CO3, HF, and H2O2 for preparing fossil plant cuticles aimed for chemical analyses is proposed, which provides an effective substitute to the conventional methods. In particular, a less aggressive and more sustainable alternative to Schulze’s solution is shown to be hydrogen peroxide, which causes only minor alteration of the fossil cuticle ’s chemical composition. Future work should carefully follow protocols, having in mind the impacts of different solutions used to treat leaves and other palaeobotanical material such as palynomorphs with aims to enable the direct comparison of spectra obtained in different studies
New species of Kuqaia from the Lower Jurassic of Sweden indicates a possible water flea (Crustacea: Branchiopoda) affinity
No full textThe enigmatic acid-resistant mesofossil genus Kuqaia isemended, anew species (Kuqaia scanicus) isinstituted, and three established species are described from the Lower Jurassic (lower Pliensbachian) ofthe Ka ̈ vlinge BH-928 core, insouthern Sweden. Kuqaia has adistribution across the middle northern latitudes ofPangaea and isrestricted toLower tolower Middle Jurassic strata. Morphological characters support Kuqaia being the ephippia (resting egg/embryo cases) ofCladocera (Crustacea: Branchiopoda), and aprobable early stemgroup taxon ofthe Daphnia lineage. The paleoecology ofthe small planktonic crustaceans indicate purely fresh-water environments, such as lakes orponds, all occurrences being in continental deposits, and the Kuqaia specimens possibly represent dry-season resting eggs. Chemical analyses ofthese and similar fossils, and ofextant invertebrate eggs and egg cases are recommended toimprove resolution ofthe biological affiliations ofsuch mesofossil groups
Response of Sm–Nd isotope systematics to complex thermal histories: A case study from 3.58 Ga gneisses of the Pilbara Craton
No full textIn felsic igneous rocks, the parent and daughter elements in the widely used Sm–Nd and Lu–Hf isotope tracer systems are mainly hosted in accessory phases. Recrystallisation and/or breakdown of these minerals during metamorphism, deformation and weathering potentially compromises the chemical and isotopic composition of the respective whole rocks, impeding the utility of such information for deducing the timing, rates and processes of crust-mantle differentiation in the early Earth. The different abilities of zircon and REE-rich minerals to withstand metamorphism have been suggested as a reason for the decoupling of the Lu–Hf and Sm–Nd isotope systems observed in a number of ancient gneiss terranes. The controls on element mobility and subsequent isotopic disturbance during recrystallisation and breakdown of LREE-rich accessory minerals are, however incompletely understood. Here, we use petrography, element mapping, and microanalysis of accessory minerals, in tandem with whole rock Sm–Nd data, to assess the reliability of the Sm–Nd system in the 3.59–3.58 Ga Mount Webber Gabbros, the oldest rocks in the Pilbara Craton (Western Australia). We show that despite multiple thermal events, which reset the mineral Sm–Nd systematics, and decomposition of the REE-rich mineral allanite, the Mount Webber rocks retained the Sm–Nd isotope signatures of their magmatic protoliths at the whole-rock scale. We show that the allanite breakdown occurred during modern, near-surface weathering processes at low temperature, such that the REE were sequestered into secondary minerals rather than escaping in higher temperature metamorphic fluids. The whole rock Sm–Nd, and zircon O–Hf signatures, together with new 142Nd isotope data, suggest derivation of the Mount Webber rocks from undifferentiated mantle sources that preserve no evidence for Hadean silicate Earth differentiation. This study highlights the benefits of a combined analytical approach using both in-situ and whole-rock isotope analyses to obtain a more complete record of the source and thermal evolution of ancient, highly metamorphosed igneous rocks