Publication Search Results

ID: 154309
Type: article
Authors: Abiem, Iveren; Arellano, Gabriel; Kenfack, David; Chapman, Hazel
Keywords: STRI
Abstract: Local factors can play an important role in defining tree species distributions in species rich tropical forests. To what extent the same applies to relatively small, species poor West African montane forests is unknown. Here, forests survive in a grassland matrix and fire has played a key role in their spatial and temporal dynamics since the Miocene. To what extent these dynamics influence local species distributions, as compared with other environmental variables such as altitude and moisture remain unknown. Here, we use data from the 20.28 ha montane forest plot in Ngel Nyaki Forest Reserve, South-East Nigeria to explore these questions. The plot features a gradient from grassland to core forest, with significant edges. Within the plot, we determined tree stand structure and species diversity and identified all trees ≥1 cm in diameter. We recorded species guild (pioneer vs. shade tolerant), seed size, and dispersal mode. We analyzed and identified to what extent species showed a preference for forest edges/grasslands or core forest. Similarly, we looked for associations with elevation, distance to streams and forest versus grassland. We recorded 41,031 individuals belonging to 105 morphospecies in 87 genera and 47 families. Around 40% of all tree species, and 50% of the abundant species, showed a clear preference for either the edge/grassland habitat or the forest core. However, we found no obvious association between species guild, seed size or dispersal mode, and distance to edge, so what leads to this sorting remains unclear. Few species distributions were influenced by distance to streams or altitude.

ID: 155290
Type: article
Authors: Adams, Rachelle M. M.; Wells, Rachel L.; Yanoviak, Stephen P.; Frost, Christopher J.; Fox, Eduardo G. P.
Keywords: NMNH; NH-Entomology; STRI
Abstract: Chemical communication is a fundamental, highly complex component of social insect societies. Ants in particular employ a remarkable diversity of chemical signals to maintain social cohesion among nestmates, gain essential resources through coordinated foraging, and warn of danger. Although the chemicals used can be functionally specific, they are vulnerable to exploitation by eavesdropping natural enemies (e.g., parasitoids, predators, parasites) and other associates (e.g., myrmecophiles). Ant nests are nutrient hotspots due to their collection of resources warranting keen defense systems; yet the heavily defended hideouts are frequently invaded. Many organisms exploit ant species, but how they locate hosts-including what host-derived cues are used-is still poorly understood. Here, we review current knowledge about how ant chemical communication systems can be exploited by unintended receivers. We take a case study approach and illustrate the diversity of ant associates and host traits that may predispose ants to exploitation. We identify knowledge gaps by reviewing host systems and listing: (1) the types of associates (e.g., fly, wasp, beetle) where eavesdropping is likely occurring, organized by the host communication system that is being exploited; (2) the ant parasites that exploit trail pheromones; and (3) the experimentally determined chemicals (i.e., alarm/defensive pheromones), used by eavesdroppers. At least 25 families of arthropods (10 orders) potentially eavesdrop on ant communication systems and nearly 20 host ant species are vulnerable to trail parasite ant species. We also propose future research that will improve our understanding of community assembly by examining host traits (e.g., latitude, nest characteristics, trail system) that influence their susceptibility to eavesdropping associates.

ID: 155492
Type: article
Authors: Aguilera, Orangel; Lopes, Ricardo T.; Rodriguez, Felix; dos Santos, Thaís M.; Rodrigues-Almeida, Caroline; Almeida, Paulo; Machado, Alessandra S.; Moretti, Tailan
Keywords: STRI
Abstract: The examined Ariidae marine catfish from the Neogene of tropical America consisted of isolated skulls, otoliths and bone fragments, some of which were described independently as otolith-based species or skull-based species. We used three-dimensional digital rendering (microCT) of skull and otolith reconstructions to recognize anatomical patterns including skull-otolith morphology, spatial allocations of otoliths in the endocranium for taxonomic identifications. We recognized isolated Proto-Caribbean otoliths of Cathorops sp. from the late early Miocene to early Pliocene formations and isolated otoliths of †Aspistor verumquadriscutis, †Bagre urumacoensis and Notarius sp. from the late Miocene. We explored the endocrania of four fossil Ariidae skulls from the late Oligocene to late early Miocene Proto-Caribbean to determine their internal otolith-cranial morphology, and we identified and described the skulls of †Bagre protocaribbeanus and †Cantarius nolfi and erected the new species of †Bagre castilloensi n. sp. and †Bagre ornatus n. sp. based on the internal otolith-skull association. The first fossil record of Bagre marinus from the early Pliocene Cubagua Formation to the late Pliocene San Gregorio Formation completed the ariid geochronological sequence. We discuss the differential stages of fossil preservation of bioapatite skulls and aragonite otoliths according to the diagenetic processes as well as the paleoenvironmental conditions in the sedimentary basins. Detailed microCT, 3D reconstructions, X-rays, dry prepared skeletons and digital photos of otolith and skull are shown to elucidate the in-skull otoliths species descriptions.

ID: 154319
Type: article
Authors: Aguilera, Orangel; Oliveira de Araújo, Olga M.; Hendy, Austin; Nogueira, Anna A. E.; Nogueira, Afonso C. R.; Wagner Maurity, Clovis; Tavares Kutter, Vinicius; Alves Martins, Maria Virginia; Coletti, Giovanni; Borba Dias, Bruna; Silva-Caminha, Silane; Jaramillo, Carlos; Bencomo, Karen; Lopes, Ricardo Tadeu
Keywords: STRI

ID: 155018
Type: article
Authors: Aiello, Annette; Stucky, Brian J.
Keywords: STRI
Abstract: Twenty-nine Pacarina (Hemiptera: Cicadidae) adults, 12 males and 17 females, emerged from the soil of a potted Dracaena trifasciata (Asparagaceae) in Arraiján, Republic of Panama, providing the first rearing records and the first definitive host plant records for any species of Pacarina. These reared Pacarina appear to be morphologically distinct from all known species of Pacarina and likely represent an undescribed species. In light of this finding, we also discuss the taxonomy, biogeography, and ecology of Pacarina.

ID: 156751
Type: article
Authors: Alfonso-Rojas, Andr; Cadena, Edwin-Alberto
Keywords: STRI
Abstract: Studies of soft tissue, cells and original biomolecular constituents preserved in fossil vertebrates have increased greatly in recent years. Here we report preservation of 'skin' with chemical and molecular characterization from a three-dimensionally preserved caudal portion of an aspidorhynchid Cretaceous fish from the equatorial Barremian of Colombia, increasing the number of localities for which exceptional preservation is known. We applied several analytical techniques including SEM-EDS, FTIR and ToF-SIMS to characterize the micromorphology and molecular and elemental composition of this fossil. Here, we show that the fossilized 'skin' exhibits similarities with those from extant fish, including the wrinkles after suffering compression stress and flexibility, as well as architectural and tissue aspects of the two main layers (epidermis and dermis). This similarity extends also to the molecular level, with the demonstrated preservation of potential residues of original proteins not consistent with a bacterial source. Our results show a potential preservation mechanism where scales may have acted as an external barrier and together with an internal phosphate layer resulting from the degradation of the dermis itself creating an encapsulated environment for the integument.

ID: 157527
Type: article
Authors: Allen, Noris Salazar; Gudiño, José A.
Keywords: STRI
Abstract: Octoblepharum peristomiruptum , a new species of moss in the family Octoblepharaceae from Panama and Brazil, is described and illustrated. The new species is characterised by plants with a reddish-purple colour particularly at the leaf bases, peristomes of eight teeth, each tooth composed of two rows of cells, fenestrate and usually completely separated at the base, strongly vertically striate-reticulate, some striations forked-like in shape. At the base of the teeth, some striations are horizontally orientated, poorly developed or absent, particularly on the cell wall that is rupturing in the separation of the vertical rows of the cells that form each tooth.

ID: 156581
Type: article
Authors: Alonso-García, Marta; Carlos, Villarreal A., Juan; McFarland, Kenneth; Goffinet, Bernard
Keywords: STRI
Abstract: The southern Appalachian (SA) is one of the most biodiversity-rich areas in North America and has been considered a refugium for many disjunct plant species, from the last glacial period to the present. Our study focuses on the SA clonal hornwort, Nothoceros aenigmaticus J. C. Villarreal & K. D. McFarland. This hornwort was described from North Carolina and is widespread in the SA, growing on rocks near or submerged in streams in six and one watersheds of the Tennessee (TR) and Alabama (AR) Rivers, respectively. Males and female populations occur in different watersheds, except in the Little Tennessee (TN) River where an isolated male population exists ca. 48 km upstream from the female populations. The sex ratio of 1:0 seems extreme in each population. In this study, we use nuclear and organellar microsatellites from 250 individuals from six watersheds (seven populations) in the SA region and two populations from Mexico (23 individuals). We, then, selected 86 individuals from seven populations and used genotyping by sequencing to sample over 600 bi-allelic markers. Our results suggest that the SA N. aenigmaticus and Mexican plants are a nested within a clade of sexual tropical populations. In the US populations, we confirm an extreme sex ratio and only contiguous US watersheds share genotypes. The phylogenetic analysis of SNP data resolves four clusters: Mexican populations, male plants (Little Pigeon and Pigeon river watersheds) and two clusters of female plants; one from the Little Tennessee and Hiwassee Rivers (TR) and the other from the Ocoee (TR) and Coosa (AR) Rivers. All clusters are highly differentiated (Fst values over 0.9). In addition, our individual assignment analyses and PCAs reflect the phylogenetic results grouping the SA samples in three clades and recovering males and female plants with high genetic differentiation (Fst values between 0.5 and 0.9 using microsatellites and bi-allelic markers). Our results point to Pleistocene events shaping the biogeographical pattern seen in US populations. The extreme sex ratio reflects isolation and highlights the high vulnerability of the populations in the SA.

ID: 155476
Type: article
Authors: Anderson-Teixeira, Kristina J.; Herrmann, Valentine; Cass, Wendy B.; Williams, Alan B.; Paull, Stephen J.; Gonzalez-Akre, Erika B.; Helcoski, Ryan; Tepley, Alan J.; Bourg, Norman A.; Cosma, Christopher T.; Ferson, Abigail E.; Kittle, Caroline; Meakem, Victoria; McGregor, Ian R.; Prestipino, Maya N.; Scott, Michael K.; Terrell, Alyssa R.; Alonso, Alfonso; Dallmeier, Francisco; McShea, William J.
Keywords: NZP; STRI
Abstract: Exotic forest insects and pathogens (EFIP) have become regular features of temperate forest ecosystems, yet we lack a long-term perspective on their net impacts on tree mortality, carbon sequestration, and tree species diversity. Here, we analyze 3 decades (1987-2019) of forest monitoring data from the Blue Ridge Mountains ecoregion in eastern North America, including 67 plots totaling 29.4 ha, along with a historical survey from 1939. Over the past century, EFIP substantially affected at least eight tree genera. Tree host taxa had anomalously high mortality rates (>= 6% year(-1) from 2008 to 2019 vs 1.4% year(-1) for less-impacted taxa). Following the arrival of EFIP, affected taxa declined in abundance (- 25 to - 100%) and live aboveground biomass (AGB; - 13 to - 100%) within our monitoring plots. We estimate that EFIP were responsible for 21-29% of ecosystem AGB loss through mortality (- 87 g m(-2) year(-1)) from 1991 to 2013 across 66 sites. Over a century, net AGB loss among affected species totaled roughly 6.6-10 kg m(-2). The affected host taxa accounted for 23-29% of genera losses at the plot scale, with mixed net effects on alpha-diversity. Several taxa were lost from our monitoring plots but not completely extirpated from the region. Despite these losses, both total AGB and alpha-diversity were largely recovered through increases in sympatric genera. These results indicate that EFIP have been an important force shaping forest composition, carbon cycling, and diversity. At the same time, less-affected taxa in these relatively diverse temperate forests have conferred substantial resilience with regard to biomass and alpha-diversity.

ID: 156578
Type: article
Authors: Anino, Yostin J.; Cambra, Roberto A.; Windsor, Donald M.; Zuniga, Ronald; Quintero, Diomedes
Keywords: STRI
Abstract: A taxonomic revision of the genus Scolia Fabricius, 1775 (Hymenoptera: Scoliidae) from Central America is presented. Two species of Scolia are present in Central America: S. (Discolia) guttata Burmeister, 1853 and S. (Hesperoscolia) rufiventris Fabricius, 1804, the latter representing the first record for Costa Rica, Panama and Colombia. The male of S. rufiventris is described and illustrated for the first time. Seasonal flight activity for S. guttata from two years of continuous Malaise trapping in Barro Colorado Island, Panama, is described

ID: 155710
Type: article
Authors: Arias, Silvina; Block, Charles; Mayfield, Derrick A.; Santillana, Gem E.; Stulberg, Michael E.; Broders, Kirk; Jackson-Ziems, Tamra; Munkvold, Gary P.
Keywords: STRI
Abstract: This paper reports original evidence regarding the potential role of seed transmission of Xanthomonas vasicola pv. vasculorum (Xvv) in the epidemiology of bacterial leaf streak (BLS) in maize. We evaluated the occurrence of the pathogen on seeds from diseased fields and its subsequent transmission to seedlings. In 2016 and 2017, Xvv was detected by TaqMan PCR from 22 of 41 maize seed lots harvested from naturally-infected fields in Colorado (CO), Nebraska (NE) and Iowa (IA). However, many of the PCR-positive samples did not yield culturable Xvv colonies. The highest levels of seed contamination were detected in dent maize and popcorn from NE and CO. Seed transmission was evaluated in greenhouse grow-outs from eight seed lots, totaling more than 14,000 plants. Putative seed transmission events from naturally contaminated seed lots, estimated from PCR results, occurred at a frequency between 0.1 and 0.5% in 10-seedling pooled samples and at a frequency of 2.7% from individual plant assays. However, no seedling symptoms were observed during these assays and live Xvv colonies were not recovered from PCR-positive seedlings. In contrast, seed transmission was readily demonstrated from artificially contaminated seed lots, including typical symptoms and recovery of live bacteria. Seed transmission consistently occurred from seeds soaked in bacterial suspensions with concentrations of ≥106 CFU per mL, suggesting that a threshold population of the bacterium is necessary for the development of BLS-symptoms and recovery of live bacteria. The low bacterial populations on naturally contaminated seeds apparently were not sufficient to result in diseased seedlings.

ID: 157073
Type: article
Authors: Atencio, Librada A.; Boya P., Cristopher A.; Martin H., Christian; Mejía, Luis C.; Dorrestein, Pieter C.; Gutiérrez, Marcelino
Keywords: STRI
Abstract: The marine bacterial genus Pseudoalteromonas is known for their ability to produce antimicrobial compounds. The metabolite-producing capacity of Pseudoalteromonas has been associated with strain pigmentation; however, the genomic basis of their antimicrobial capacity remains to be explained. In this study, we sequenced the whole genome of six Pseudoalteromonas strains (three pigmented and three non-pigmented), with the purpose of identifying biosynthetic gene clusters (BGCs) associated to compounds we detected via microbial interactions along through MS-based molecular networking. The genomes were assembled and annotated using the SPAdes and RAST pipelines and mined for the identification of gene clusters involved in secondary metabolism using the antiSMASH database. Nineteen BGCs were detected for each non-pigmented strain, while more than thirty BGCs were found for two of the pigmented strains. Among these, the groups of genes of nonribosomal peptide synthetases (NRPS) that code for bromoalterochromides stand out the most. Our results show that all strains possess BGCs for the production of secondary metabolites, and a considerable number of distinct polyketide synthases (PKS) and NRPS clusters are present in pigmented strains. Furthermore, the molecular networking analyses revealed two new molecules produced during microbial interactions: the dibromoalterochromides D/D' (11–12).

ID: 157333
Type: article
Authors: Avila-Lovera, Eleinis; Garcillan, Pedro P.; Silva-Bejarano, Christian; Santiago, Louis S.
Keywords: STRI
Abstract: Premise Photosynthetic stems represent a source of extra carbon in plants from hot and dry environments, but little is known about how leaves and photosynthetic stems differ in terms of photosynthetic capacity, trait coordination, and responses to seasonal drought in subtropical systems. Methods We studied photosynthetic, hydraulic, morphometric (specific leaf area [SLA], wood density [WD]), and biochemical (C and N isotopes) traits in leaves and photosynthetic stems of 12 plant species from a sarcocaulescent scrub in the southern Baja California Peninsula, Mexico, in wet and dry seasons. Results Leaves and stems had similar mean photosynthetic capacity, as evaluated by chlorophyll fluorescence traits, indicating similar investment in leaf and stem photosynthesis. We did not find a relationship between stem hydraulic conductivity and leaf or stem photosynthetic traits. However, we found resource allocation trade-offs, between WD and both stem hydraulic conductivity and SLA. Leaf and stem photosynthetic traits did not change with season, but specific stem area was one of the few traits that changed the most between seasons-it increased during the dry season by as much as 154% indicating substantial water storage. Conclusions Our results indicate the same proportional investment in photosynthetic capacity and dry matter in both leaves and photosynthetic stems across all 12 species. We identified multiple strategies at this seasonal site, with species ranging from high WD, low SLA, low hydraulic conductivity, and high specific bark area on one end of the spectrum and opposite traits on the other end.

ID: 153430
Type: article
Authors: Baldwin, Justin W.; Dechmann, Dina K. N.; Thies, Wibke; Whitehead, Susan R.
Keywords: STRI
Abstract: The paradoxical presence of toxic chemical compounds in ripe fruits represents a balance between plant enemies and allies: chemical traits can defend seeds against antagonistic herbivores, seed predators or fungal pathogens, but also can impose costs by repelling mutualistic seed dispersers, although the costs are often difficult to quantify. Seeds gain fitness benefits from travelling far from the parent plant, as they can escape from parental competition and elude specialized herbivores as well as pathogens that accumulate on adult plants. However, seeds are difficult to follow from their parent plant to their final destination. Thus, little is known about the factors that determine seed dispersal distance. We investigated this potential cost of fruit secondary compounds – reduced seed dispersal distance - by combining two datasets from previous work on a Neotropical bat-plant dispersal system (bats in the genus Carollia and plants in the genus Piper). We used data from captive behavioral experiments, which show how amides in ripe fruits of Piper decrease the retention time of seeds and alter food choices. With new analyses, we show that these defensive secondary compounds also delay the time of fruit removal. Next, with a behaviorally annotated bat telemetry dataset, we quantified post-feeding movements (i.e. seed dispersal distances). Using generalized additive mixed models we found that seed dispersal distances varied nonlinearly with gut retention times as well as with the time of fruit removal. By interrogating the model predictions, we identified two novel mechanisms by which fruit secondary compounds can impose costs in terms of decreased seed dispersal distances: 1) small scale reductions in gut retention time and 2) causing fruits to forgo advantageous bat activity peaks that confer high seed dispersal distances.

ID: 154064
Type: article
Authors: Barco, R. A.; Garrity, G. M.; Scott, J. J.; Amend, J. P.; Nealson, K. H.; Emerson, D.
Keywords: STRI
Abstract: Genus assignment is fundamental in the characterization of microbes, yet there is currently no unambiguous way to demarcate genera solely using standard genomic relatedness indices. Here, we propose an approach to demarcate genera that relies on the combined use of the average nucleotide identity, genome alignment fraction, and the distinction between type- and non-type species. More than 3,500 genomes representing type strains of species from >850 genera of either bacterial or archaeal lineages were tested. Over 140 genera were analyzed in detail within the taxonomic context of order/family. Significant genomic differences between members of a genus and type species of other genera in the same order/family were conserved in 94% of the cases. Nearly 90% (92% if polyphyletic genera are excluded) of the type strains were classified in agreement with current taxonomy. The 448 type strains that need reclassification directly impact 33% of the genera analyzed in detail. The results provide a first line of evidence that the combination of genomic indices provides added resolution to effectively demarcate genera within the taxonomic framework that is currently based on the 16S rRNA gene. We also identify the emergence of natural breakpoints at the genome level that can further help in the circumscription of taxa, increasing the proportion of directly impacted genera to at least 43% and pointing at inaccuracies on the use of the 16S rRNA gene as a taxonomic marker, despite its precision. Altogether, these results suggest that genomic coherence is an emergent property of genera in Bacteria and ArchaeaIMPORTANCE In recent decades, the taxonomy of Bacteria and Archaea, and therefore genus designation, has been largely based on the use of a single ribosomal gene, the 16S rRNA gene, as a taxonomic marker. We propose an approach to delineate genera that excludes the direct use of the 16S rRNA gene and focuses on a standard genome relatedness index, the average nucleotide identity. Our findings are of importance to the microbiology community because the emergent properties of Bacteria and Archaea that are identified in this study will help assign genera with higher taxonomic resolution.

ID: 156400
Type: article
Authors: Barreda, Viviana D.; Zamaloa, María del Carmen; Gandolfo, María A.; Jaramillo, Carlos; Wilf, Peter
Keywords: STRI

ID: 155497
Type: article
Authors: Bashevkin, Samuel M.; Christy, John H.; Morgan, Steven G.
Keywords: STRI

ID: 155908
Type: article
Authors: Basset, Yves; Palacios-Vargas, Jos; Donoso, David A.; Castaño-Meneses, Gabriela; Decaëns, Thibaud; Lamarre, Greg P.; De León, Luis F.; Rivera, Marleny; García-Gómez, Arturo; Perez, Filonila; Bobadilla, Ricardo; Lopez, Yacksecari; Ramirez, José Alejandro; Cruz, Maira Montejo; Galván, Angela Arango; Mejía-Recamier, Blanca E.; Barrios, Héctor
Keywords: STRI

ID: 156401
Type: article
Authors: Batista de Vega, Gloria; Ulloque N, Carlos E.; Hurtado, Anicia Q.; Cornish, Lynn; Critchley, Alan T.
Keywords: STRI

ID: 154061
Type: article
Authors: Bell‐Doyon, Philip; Laroche, Jérôme; Saltonstall, Kristin; Villareal Aguilar, Juan Carlos
Keywords: STRI
Abstract: Epiphytes face several constraints regarding nutrient acquisition: They are disconnected from soil minerals and they have to mainly rely on nutrients leached by precipitation and microbes. The cycad, Zamia pseudoparasitica Yates, is the only known strictly epiphytic gymnosperm, and it is endemic to Panamanian rainforests. Cycads have evolved specialized coralloid roots that host endophytic cyanobacteria specialized in nitrogen fixation. We collected coralloid roots from plants in the Omar Torrijos National Park, Provincia de Coclé. DNA was extracted from fresh inner coralloid roots, and the bacteriome was described using two molecular markers: rbcL-rbcX (targeting cyanobacteria) and 16S (all bacteria). Sixteen samples were sequenced for rbcL-rbcX yielding sequences belonging to a monophyletic group within the order Nostocales. One hundred and sixty-five amplicon sequence variants (ASVs) were found in at least two of our 27 samples amplified for 16S. Nostocales, Rhizobiales, and Acetobacterales were the three most diverse and abundant orders of bacteria found within the coralloid roots, and the candidate phylum WPS-2 was also found in many samples. We performed a de novo assembly from a single culture of the endophytic cyanobacteria. A phylogenomic analysis of the isolate places the cyanobacterium in a sister clade to mostly symbiotic taxa from mosses, liverworts, and lichens. Additionally, the isolate has genes putatively involved in symbiotic signaling, hormogonium differentiation, ammonium transport, nitrogen fixation, heterocyst differentiation, sulfate transport, and secondary metabolites. Although dominated by organisms with the capacity to fix nitrogen, coralloid roots are also inhabited by a diverse community of other taxa which may also play biologically important roles.