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Nine new species of Hyperaspis from various South American localities are described, illustrated, and compared with previously described taxa. New taxa are: Hyperaspis luciae, H. corcovado, H. divaricata, H. humboldti, H. mimica, H. praecipua, H. unimaculosa, H. drechseli, and H. esmeraldas. Hyperaspis pectoralis Crotch is recognized as a valid species of Hyperaspis and integrated into the existing classification.
The quasi-free scattering reactions 11C(p, 2p) and 10,11,12C(p, pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the R3B-LAND setup. The outgoing proton-proton and protonneutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the 12C(p, 2p) and 12C(p, pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of singleparticle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p, 2p) are found to be ’significantly smaller than for (p, pn) reactions for all investigated nuclei.
Species of Calloeneis Grote (Coleoptera: Coccinellidae) are discussed, and a key to all recognized species is provided. New species described are C. alexandra, C. angelica, C. blanca, C. bennetti, C. bethany, C.brooke, C. francis, C. jacquelin, C. johnnie, C. kara, C. krista, C. leticia, C. lynne, C. robyn, C. marianne, C. myra,C. rosalie, C. roxanne and C. sheri, all authored by Gordon and Hanley.
Twenty new species are described in Pentilia Mulsant (Coleoptera: Coccinellidae: Scymninae: Cryptognathini) by Gordon and González: Pentilia bernadette, P. chelsea, P. dianna, P. elena, P. ernestine, P. estelle, P. kari, P. jasmine, P. jody, P. kendra. P. krystal, P. lora, P. mable, P. muriel, P. nichole, P. nadine. P. paulette, P. rachael, P. sadie and P. traci. A lectotype is here designated for Pentilia egena Mulsant.
Genera of Cryptognathini (Coleoptera: Coccinellidae) are discussed and a key to all recognized genera is provided. Cryptognatha is revised, and species of this genus are keyed. New species, authored by González and Hanley, are Cryptognatha pam, C. kellie, C. hannah, C. whitney, C. karla, C. celia, C. shelia, C. gayle, C. della and C. vicki. The following new synonymies are proposed: Cryptognatha simillima Sicard = Cryptognatha gemellata Mulsant, Cryptognatha fryii Crotch = Cryptognatha pudibunda Mulsant, Cryptognatha bryanti Brèthes = Cryptognatha pudibunda Mulsant. Lectotypes are here designated for Cryptognatha amicta Gorham, C. weisei Brèthes, C. pudibunda Mulsant and C. fryii Crotch.
The Colombian fluted scale (CFS), Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae) is a polyphagous scale insect which affects about 100 species of plants. Between 2010–2013, the species was reported as an invasive pest on the islands of San Andres and Old Providence, Colombian territory in the Caribbean sea.
Currently, populations of the CFS also have increased in the city of Cali, Valle del Cauca State, mainland Colombia, affecting different host plants, especially leguminous trees such as Caesalpinia peltophoroides Benth., Pithecellobium dulce (Roxb.) Benth., P. saman (Jacq.) Benth. (Fabaceae) and mango, Mangifera indica L. (Anacardiaceae). With the aim of searching for natural enemies to control the CFS, field studies were conducted in the city of Cali between February 2013 and October 2014. As a result of this study, two species of lady beetles were found feeding on CFS, i.e., Anovia punica Gordon and Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae). This is the first record of R. cardinalis preying on CFS.
The ladybeetle Anovia sp. (Coleoptera: Coccinellidae: Noviini), known as an important natural enemy of the Colombian fluted scale, Crypticeria muticicatrices Kondo and Gullan (Hemiptera: Coccoidea: Monophlebidae) is here identified as A. punica Gordon, 1972, and reported for the first time from Peru. Here we provide information and illustrations of the great variation in color and dorsal patterns of A. punica found in Colombia and Peru.
The first reports of the multicolored Asian lady beetle Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) in Colombia appeared in 2011. However, based on museum insect specimens, the introduction of H. axyridis in Colombia occurred in 1989 or earlier, making it the second oldest record of the species in South America after the deliberate releases of the species in Argentina in 1986. Currently in Colombia, H. axyridis is well established and is here recorded from the States of Antioquia, Caldas, Cauca, Cundinamarca, Nariño, Tolima and Valle del Cauca.
Delphastus quinculus Gordon and Diomus seminulus (Mulsant) (Coleoptera: Coccinellidae) are reported for the first time feeding on eggs and first-instar nymphs of Crypticerya multicicatrices Kondo and Unruh (Hemiptera: Monophlebidae). Diagnosis and illustrations are provided for both species. Updated information on their biology, hosts and geographical distribution is also provided.
In recent years, populations of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), have increased in rural citrus orchards and urban backyard gardens. In order to fi nd biological control options for D. citri, a search for natural enemies was conducted in the department of Valle del Cauca, Colombia. The collections were carried out in citrus orchards in rural areas and house gardens and street trees in urban areas.
Natural enemies were collected from D. citri found on Citrus spp. and Murraya paniculata (L.) Jack (Rutaceae). A total of 16 species of natural enemies of D. citri distributed in six families in fi ve orders are reported from Colombia.
Herein we provide an updated list of 95 species of arthropod (arachnids and insects) natural enemies of D. citri distributed in nine orders and 23 families recorded worldwide.
The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the spin-orbit shell gap towards the neutron dripline. To do so, we employed (p,2p) quasi-free scattering reactions to measure the proton component of the state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton spin-orbit splitting, at variance to recent claims for a prevalent magic number towards the neutron dripline.
The neutron-unbound isotope 13Be has been studied in several experiments using different reactions, different projectile energies, and different experimental setups. There is, however, no real consensus in the interpretation of the data, in particular concerning the structure of the low-lying excited states. Gathering new experimental information, which may reveal the 13Be structure, is a challenge, particularly in light of its bridging role between 12Be, where the N = 8 neutron shell breaks down, and the Borromean halo nucleus 14Be. The purpose of the present study is to investigate the role of bound excited states in the reaction product 12Be after proton knockout from 14B, by measuring coincidences between 12Be, neutrons, and γ rays originating from de-excitation of states fed by neutron decay of 13Be. The 13Be isotopes were produced in proton knockout from a 400 MeV/nucleon 14B beam impinging on a CH2 target. The 12 Be-n relative-energy spectrum d σ /d Ef n was obtained from coincidences between 12Be(g.s.) and a neutron, and also as threefold coincidences by adding γ rays, from the de-excitation of excited states in 12Be. Neutron decay from the first 5/2+ state in 13Be to the 2+ state in 12Be at 2.11 MeV is confirmed. An energy independence of the proton-knockout mechanism is found from a comparison with data taken with a 35 MeV/nucleon 14B beam. A low-lying p-wave resonance in 13Be(1/2−) is confirmed by comparing proton- and neutron-knockout data from 14B and 14Be.
Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R3B/LAND setup with incident beam energies in the range of 300–450 MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type AO(p,2p)A−1N have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.
The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process β-decay chains. These nuclei are attributed to the p and rp process.
For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections.
The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.