Acorn consumption improves the immune response of the dung beetle Thorectes lusitanicus

Thorectes lusitanicus, a typically coprophagous species is also actively attracted to oak acorns, consuming, burying them, and conferring ecophysiological and reproductive advantages to both the beetle and the tree. In this study, we explored the possible relation between diet shift and the health status of T. lusitanicus using a generalist entomopathogenic fungus (Metarhizium anisopliae) as a natural pathogen. To measure the health condition and immune response of beetles, we analysed the protein content in the haemolymph, prophenoloxidase (proPO) content, phenoloxidase (PO) activity and mortality of beetles with diets based on either acorns or cow dung. Protein content, proPO levels and PO levels in the haemolymph of T. lusitanicus were found to be dependent on the type of diet. Furthermore, the beetles fed with acorns developed a more effective proPO-PO system than the beetles fed with cow dung. Furthermore, a significant decrease in mortality was observed when infected individuals were submitted to an acorn-based diet. In addition to enhancing an understanding of the relevance of dietary change to the evolutionary biology of dung beetles, these results provide a more general understanding of the ecophysiological implications of differential dietary selection in the context of fitness.

Culturable aerobic and facultative bacteria from the gut of the polyphagic dung beetle Thorectes lusitanicus Jeckel

Unlike other dung beetles, the Iberian geotrupid Thorectes lusitanicus exhibits polyphagous behavior; for example, it is able to eat acorns, fungi, fruits, and carrion in addition to the dung of different mammals. This adaptation to digest a wider diet has physiological and developmental advantages and requires key changes in the composition and diversity of the beetle's gut microbiota. In this study, we isolated aerobic, facultative anaerobic, and aerotolerant microbiota amenable to grow in culture from the gut contents of T. lusitanicus and resolved isolate identity to the species level by sequencing 16S rRNA gene fragments. Using BLAST similarity searches and maximum likelihood phylogenetic analyses, we were able to reveal that the analyzed fraction (culturable, aerobic, facultative anaerobic, and aerotolerant) of beetle gut microbiota is dominated by the phyla Proteobacteria, Firmicutes and Actinobacteria. Among Proteobacteria, members of the order Enterobacteriales (Gammaproteobacteria) were the most abundant. The main functions associated with the bacteria found in the gut of T. lusitanicus would likely include nitrogen fixation, denitrification, detoxification, and diverse defensive roles against pathogens.

The comparative effectiveness of rodents and dung beetles as local seed dispersers in Mediterranean oak forests

The process of seed dispersal of many animal-dispersed plants is frequently mediated by a small set of biotic agents. However, the contribution that each of these dispersers makes to the overall recruitment may differ largely, with important ecological and management implications for the population viability and dynamics of the species implied in these interactions. In this paper, we compared the relative contribution of two local guilds of scatter-hoarding animals with contrasting metabolic requirements and foraging behaviours (rodents and dung beetles) to the overall recruitment of two Quercus species co-occurring in the forests of southern Spain. For this purpose, we considered not only the quantity of dispersed seeds but also the quality of the seed dispersal process. The suitability for recruitment of the microhabitats where the seeds were deposited was evaluated in a multi-stage demographic approach. The highest rates of seed handling and predation occurred in those microhabitats located under shrubs, mostly due to the foraging activity of rodents. However, the probability of a seed being successfully cached was higher in microhabitats located beneath a tree canopy as a result of the feeding behaviour of beetles. Rodents and beetles showed remarkable differences in their effectiveness as local acorn dispersers. Quantitatively, rodents were much more important than beetles because they dispersed the vast majority of acorns. However, they were qualitatively less effective because they consumed a high proportion of them (over 95%), and seeds were mostly dispersed under shrubs, a less suitable microhabitat for short-term recruitment of the two oak species. Our findings demonstrate that certain species of dung beetles (such as Thorectes lusitanicus), despite being quantitatively less important than rodents, can act as effective local seed dispersers of Mediterranean oak species. Changes in the abundance of beetle populations could thus have profound implications for oak recruitment and community dynamics.

On the Upper Cretaceous age and affinities of Neocyprideis lusitanicus (Ostracoda)

Guernet & Lauverjat (1986) described a new species, Neocyprideis lusitanicus, from sediments deposited near Aveiro, Portugal. For these authors, some associated fossils (Molluscs, planktonic Foraminifera) indicated a Pliocene age. That seemingly was the first record of Neocyprideis in post-Miocene sediments in Europe. A recent study of Upper Cretaceous material from the same region showed an abundant Neocyprideis fauna, associated with Charophyta. These Neocyprideis could be assigned without any doubt to N. lusitanicus. Therefore, N. lusitanicus appears as an Upper Cretaceous species, reworked in much later sediments, not Pliocene but Quaternary, as indicated by the planktonic Foraminifera assemblage. This interpretation is supported by: 1 - the incompatibility of the Neocyprideis (restricted to lacustrine-lagoonal environments) with abundant planktic Foraminifera; 2 - the occurrence of N. lusitanicus with Charophytes and non marine, cretaceous vertebrates but without the same Foraminifera. Neocyprideis lusitanicus is a valid species, clearly different from the other late Cretaceous species (N. coudouxensis and N. murciensis) as well as the Early Miocene described species (N. aquitanica, N. janoscheki).

Nuevo registro de Thorectes valencianus Baraud, 1966 (Coleoptera: Geotrupidae) para el sudeste iberolevantino (España)

En este trabajo se aporta una nueva cita para Thorectes valencianus (Coleoptera: Geotrupidae). Este coleóptero es un endemismo iberolevantino catalogado como Vulnerable en la lista roja de la UICN y localizado en la sierra de Escalona (Orihuela, Alicante).

Problèmes posés par la population sporo-pollinique d'un niveau à plantes de la série de Buarcos (Portugal)

L'analyse pollinique des sédiments argileux, riches en macrorestes de végétaux, du "Belasien» (Crétacé inférieur) de Buarcos a permis reconnaître la présence d'une riche microflore. On a, nottament, reconnu la présence de: Concavisporites punctatus, Auritulinosporites complexis, Chomotriletes sp., Trilobosporites cf. bernissartensis, Apiculatisporites vulgaris, Cicatricosisporites sp. 1, Cicatricosisporites sp. 2. Cicatricosisporites sp. 3, Cicatricosisporites sp. 4, Cicatricosisporites sp. 5, Cicatricosisporites sp. 6. Costatoperforosporites fistulosus, Ceratosporites sp. l, C. cf. equalis, Ischyosporites teixeirae n. sp., Liburnisporites sp. AequitriraditeS cf. spinulosus, Cedripites lusitanicus, Clavatipollenites cf. hughesi. Après discution de la stratigraphie des diffèrentes espèces on sugère une âge barremo-aptien pour cette association malgré la présence de l'ensemble Apiculalisporites vulgaris-Classopollls major plutôt d'âge Aptien.

Limnic ostracoda from Silveirinha, Portugal (? Late Paleocene - Lowermost Eocene)

Silveirinha, a rich site for mammals and other vertebrates, yielded some molluscs, charophytes and ostracods. The latter are described here. Eight species were recognized. Two of them, Ilyocypris lusitanicus n. sp. and Cypris silveirinhaensis n. sp. are new. Other, unnamed species may be ascribed to Cyclocypris? and Cypria? besides a further four undeterminate Cypridacea. The Ostracod association is typical for limnic environments and is compatible with intertropical conditions. Cypris silveirinhaensis suggests an Eocene, and especially a lower Eocene age.

Nesticus baeticus sp. n., a new troglobitic spider species from south-west Europe (Araneae, Nesticidae)

A new troglobitic species, Nesticus baeticus sp. n. (♂♀), inhabiting the karst landscapes of the high part of the Cazorla, Segura and Las Villas Natural Park (NE Jaén, Spain) where it has been found in 8 caves is diagnosed and described, its distribution and habitat are also analyzed.The new species belongs to the Iberian species group that includes Nesticus luquei, Nesticus lusitanicus and Nesticus murgis. Evolutionary relationships of the Iberian Nesticus species are discussed on the basis of morphological and molecular data (cox1 and rrnL). Arachnida, Araneae, taxonomy, description, new species, caves, Iberian Peninsula, Mediterranean basin

Táxons de Mucor Fresen. (Zygomycota) em fezes de herbívoros, Recife, PE, Brasil

Visando contribuir para o conhecimento sobre Mucorales (Zygomycota) em Recife, PE, foram realizadas coletas mensais, de junho/1997 a maio/1998, totalizando 120 amostras de fezes dos herbívoros: Bison bonasus H. Smith, Bos indicus L., Bubalus bubalis H. Smith, Capra hircus L., Oryctolagus cuniculus Lilljeborg, Dasyprocta fuliginosa Wagler, Taurotragus oryx Wagner, Equus caballus L., Ovis aries L. e Mazama gouazoubira Fischer, mantidos em cativeiro no Parque Dois Irmãos e no Departamento de Zootecnia da Universidade Federal Rural de Pernambuco. As amostras de fezes foram acondicionadas em câmara úmida (placa de Petri) à temperatura ambiente sendo observadas diariamente, do 2º ao 15º dia de incubação. As colônias de interesse foram isoladas e, após desenvolvimento, mantidas em Batata Dextrose Ágar (BDA) e/ou "Synthetic Mucor Agar" (SMA). Foram identificados 11 táxons já conhecidos e uma forma nova: Mucor circinelloides f. circinelloides, M. circinelloides f. griseocyanus, M. circinelloides f. janssenii, M. circinelloides f. lusitanicus, M. hiemalis f. hiemalis, M. hiemalis f. luteus, M. genevensis, M. piriformis f. piriformis, M. piriformis f. nanus, M. racemosus f. chibinensis, M. subtilissimus e M. variosporus. Com exceção das fezes de Bubalus bubalis, todas desenvolveram representantes de táxons de Mucor, apresentando maior diversidade as fezes de Bison bonasus, Oryctolagus cuniculus, Dasyprocta fuliginosa e Mazama gouazoubira. O maior índice de similaridade (75%) foi verificado em táxons de Mucorales nas fezes de Dasyprocta fuliginosa e Ovis aries, assim como de Capra hircus e Oryctolagus cuniculus. Chave para identificação dos táxons isolados, assim como descrições, comentários e ilustrações foram incluídos.

Mucorales de solo contaminado com metais pesados na região do pólo cerâmico de Santa Gertrudes, SP: ocorrência e capacidade de biossorção de chumbo e zinco

Pós-graduação em Ciências Biológicas (Microbiologia Aplicada) - IBRC

Revision of Trogulidae Sundevall, 1833 (Arachnida: Opiliones)

The relationship and phylogeny of the western Palearctic harvestmen family Trogulidae is investigated. The traditional system of seven genera and approximately 40 species appeared to be artificially composed but a phylogenetic approach and a comprehensive revision has long been sought after. Species are poorly characterised due to their uniform morphology and species evaluation is furthermore complicated by the variability of the few characters used for species delineation. To meet these demands a molecular genetic analysis is accomplished using the nuclear 28S rRNA gene and the mitochondrial cytochrome b gene. This analysis incorporates most genera and species of Trogulidae as well as a comprehensive set of Nemastomatidae and Dicranolasmatidae as outgroup taxa. Phylogenetic results of Bayesian analysis, Maximum Parsimony, Maximum Likelihood and Neighbor Joining are compared with distributional data, morphological characters and results of canonical discriminant analysis of morphometric characters and general congruence of these data sets is shown. To demonstrate the applicability of this method the revision of two species-groups within Trogulus is set out in detail. The Trogulus hirtus species-group and the Trogulus coriziformis species-group are revised. The former is in the central and north-western Balkan Peninsula. T. tricarinatus ssp. hirtus is raised to species level and four new species are described (T. karamanorum [man.n.], T. melitensis [man.n.], T. pharensis [man.n]; T. thaleri [man.n.]). The Trogulus coriziformis species-group is confined to the western Mediterranean area. T. coriziformis, T. aquaticus are re-described, T. cristatus and T. lusitanicus are re-established and four species are described as new (T. balearicus, T. huberi, T. prietoi, T. pyrenaicus). In both species-groups two further cryptic species probably exist but were not described. The species groups are shown to represent different phylogenetic levels and this information is used for the revisional work on the genus Trogulus as well as for the generic system of Trogulidae. Family status of Dicranolasmatidae is rejected and Dicranolasma is shown to be best incorporated within Trogulidae. Calathocratus, Platybessobius and Trogulocratus appear to be polyphyletic and are best to be united within Calathocratus, the oldest name of this set. The cryptic diversity within Trogulidae, especially in Trogulus and the composed genus Calathocratus rates to 150-235% and is thereby remarkably high for a group of the generally well researched European fauna. Genetic features of the group such as heteroplasmy, the possibility of major gene rearrangements and usability of the cytochrome b gene for phylogenetic studies in Opiliones are outlined.

Gastropod Seed Dispersal: An Invasive Slug Destroys Far More Seeds in Its Gut than Native Gastropods

Seed dispersal is one of the most important mechanisms shaping biodiversity, and animals are one of the key dispersal vectors. Animal seed dispersal can directly or indirectly be altered by invasive organisms through the establishment of new or the disruption of existing seed dispersal interactions. So far it is known for a few gastropod species that they ingest and defecate viable plant seeds and consequently act as seed dispersers, referred to as gastropodochory. In a multi-species experiment, consisting of five different plant species and four different gastropod species, we tested with a fully crossed design whether gastropodochory is a general mechanism across native gastropod species, and whether it is altered by the invasive alien slug species Arion lusitanicus. Specifically, we hypothesized that a) native gastropod species consume the seeds from all tested plant species in equal numbers (have no preference), b) the voracious invasive alien slug A. lusitanicus – similarly to its herbivore behaviour – consumes a higher amount of seeds than native gastropods, and that c) seed viability is equal among different gastropod species after gut passage. As expected all tested gastropod species consumed all tested plant species. Against our expectation there was a difference in the amount of consumed seeds, with the largest and native mollusk Helix pomatia consuming most seeds, followed by the invasive slug and the other gastropods. Seed damage and germination rates did not differ after gut passage through different native species, but seed damage was significantly higher after gut passage through the invasive slug A. lusitanicus, and their germination rates were significantly reduced.

Locomotor activity of two sympatric slugs: implication for the invasion success of terrestrial invertebrates.

A central focus of invasion biology is to identify the traits that predict which introduced species will become invasive. Behavioral traits related to locomotor activity most likely play a pivotal role in determining a species’invasion success but have rarely been studied, particularly in terrestrial invertebrates. Here, we experimentally investigated the small-scale locomotor activity of two slug species with divergent invasion success in Europe, the highly invasive slug, Arion lusitanicus, and the closely related, non-invasive and native slug, Arion rufus. To do so, we used a multi-state capture-mark-recapture approach, and hypothesized that the invasive slug has a higher moving rate (keeps on moving) and leaving rate (leaves more frequently known places). A total of 221 invasive and 241 non-invasive slugs were individually marked using magnetic transponders and released in three study sites differing in habitat type. The slugs were recaptured using shelter traps, and moving and leaving rates were estimated. Both rates were significantly higher for the invasive slug, demonstrating a higher locomotor activity which might partly explain its invasion success. Our results provide evidence for the recently suggested idea that locomotor activity might be an important trait underlying animal invasions using for the first time terrestrial invertebrates.

The role of glucosinolates and the jasmonic acid pathway in resistance of Arabidopsis thaliana against molluscan herbivores

Although slugs and snails play important roles in terrestrial ecosystems and cause considerable damage on a variety of crop plants, knowledge about the mechanisms of plant immunity to molluscs is limited. We found slugs to be natural herbivores of Arabidopsis thaliana and therefore investigated possible resistance mechanisms of this species against several molluscan herbivores. Treating wounded leaves with the mucus residue (‘slime trail’) of the Spanish slug Arion lusitanicus increased wound-induced jasmonate levels, suggesting the presence of defence elicitors in the mucus. Plants deficient in jasmonate biosynthesis and signalling suffered more damage by molluscan herbivores in the laboratory and in the field, demonstrating that JA-mediated defences protect A. thaliana against slugs and snails. Furthermore, experiments using A. thaliana mutants with altered levels of specific glucosinolate classes revealed the importance of aliphatic glucosinolates in defending leaves and reproductive structures against molluscs. The presence in mollusc faeces of known and novel metabolites arising from glutathione conjugation with glucosinolate hydrolysis products suggests that molluscan herbivores actively detoxify glucosinolates. Higher levels of aliphatic glucosinolates were found in plants during the night compared to the day, which correlated well with the nocturnal activity rhythms of slugs and snails. Our data highlight the function of well-known antiherbivore defence pathways in resistance against slugs and snails and suggest an important role for the diurnal regulation of defence metabolites against nocturnal molluscan herbivores.

Development and characterization of novel microsatellite markers for Arion slug species

Seventeen polymorphic microsatellite markers were isolated and characterized in Arion vulgaris/lusitanicus, which belongs to the worst European slug pests with serious economic and ecological impact. These markers were tested on 23 individuals collected in a population in Switzerland. Numbers of alleles ranged from 2 to 14 per locus, observed and expected heterozygosities ranged from 0.174 to 0.87, and from 0.162 to 0.903, respectively. These loci were also successfully amplified and were polymorphic in the closely related species A. rufus and A. ater. These loci represent the first highly polymorphic nuclear markers described for A. vulgaris and pave the way for population genetics and molecular ecology research of the important Arion pest slugs.