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1. Tometes kranponhah and Tometes ancylorhynchus (Characiformes: Serrasalmidae), two new phytophagous serrasalmids, and the first Tometes species described from the Brazilian Shield

   https://doi.org/10.1111/jfb.12868  

   Andrade, M. C. ; Jégu, M. ; Giarrizzo, T. ( January 2016 , Journal of Fish Biology)

   Two new species ofTometesfrom the Brazilian Shield rapids are described.Tometes kranponhahis endemic to the Xingu River basin, whereasTometes ancylorhynchusoccurs both in the Xingu and the Tocantins–Araguaia River basins. The two species are sympatric in the Xingu drainages and have many similarities in morphology and colouration. Major diagnostic differences are the dark pigmentation on the opercle ofT. kranponhahand its distinct snout shape and arrangement of premaxillary teeth. In addition,T. kranponhahis a large fish that is abundant in the Xingu River, whereasT. ancylorhynchusis a medium‐sized fish for which there are few records.

    

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2. Zhuotingoxylon liaoi gen. et sp. nov., a silicified coniferous trunk from the Changhsingian (Permian) of southern Bogda Mountains, northwestern China

   https://doi.org/10.1002/gj.4189  

   Wan, Mingli ; Yang, Wan ; Wang, Keyu ; Liu, Lujun ; Wang, Jun ( June 2021 , Geological Journal)

   A silicified trunk,Zhuotingoxylon liaoiWan, Yang, Wang, Liu et Wang gen. et sp. nov., is described from the uppermost part of Guodikeng Formation in South Taodonggou section, Turpan–Hami Basin, Xinjiang Uygur Autonomous Region, northwestern China. It is characterized by a solid pith, endarch primary xylem and pycnoxylic wood. The pith is composed of parenchyma and sclereids. Radial walls of primary xylem tracheids have spiral and scalariform thickenings. Secondary xylem consists of thick‐walled tracheids and parenchymatous rays. Uniseriate rounded pits with oval apertures are distributed on radial tracheidal walls separately. Cell walls of rays are homogeneous and smooth. Rays are 1–10 cells high in tangential section. Cross‐field pits are cupressoid. There are 1–4 bordered pits with slit‐like to oval apertures in each cross‐field. Based on the anatomical features of the pith and xylems, it is proposed that the new stem has a coniferous affinity. The new fossil stem adds to the knowledge of vascular plant diversity close to the Permian–Triassic boundary.

    

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3. Dispersion of the invasive common carp Cyprinus carpio in southern South America: changes and expectations, westward and southward

   https://doi.org/10.1111/jfb.12969  

   Crichigno, S. ; Cordero, P. ; Blasetti, G. ; Cussac, V. ( April 2016 , Journal of Fish Biology)

   Common carpCyprinus carpiopossess multiple traits that contribute to their success as an invasive species. They have been introduced across the globe, and abundant populations can have numerous negative effects. Although ecological niche‐based modelling techniques have been used to predict the potential range ofC. carpioinvasion in U.S.A., occurrence and abundance patterns have not yet been considered on a regional scale. In the present review new locations are documented, the status of the southernmost population has been studied and the probability of new lakes and reservoirs being colonized byC. carpiohas been obtained and related to environmental conditions. The new localities forC. carpiohave expanded its distribution westward, into the Andean Region, and present results from the South American southernmost population have shown a well‐established population. Analysis of presence data provided two principal results: (1) the probability of a site being withC. carpiocan be inferred using environmental variables and (2) the probability of a site being withC. carpiois a useful tool for the prediction of future invasions. Selective fishing on the Negro basin could constitute a potential mitigation measure, decreasing the abundance of the species and thus reducing the species' potential for southward expansion. These results reinforce the idea that artisanal fisheries, food production and conservation interests should be taken into account by local government management agencies in any discussion regarding the southern distribution ofC. carpioin the near future.

    

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4. The development of cephalic armor in the tokay gecko (Squamata: Gekkonidae: Gekko gecko )

   https://doi.org/10.1002/jmor.21092  

   Laver, Rebecca J. ; Morales, Cristian H. ; Heinicke, Matthew P. ; Gamble, Tony ; Longoria, Kristin ; Bauer, Aaron M. ; Daza, Juan D. ( December 2019 , Journal of Morphology)

   Armored skin resulting from the presence of bony dermal structures, osteoderms, is an exceptional phenotype in gekkotans (geckos and flap‐footed lizards) only known to occur in three genera:Geckolepis,Gekko, andTarentola. The Tokay gecko (Gekko geckoLINNAEUS 1758) is among the best‐studied geckos due to its large size and wide range of occurrence, and although cranial dermal bone development has previously been investigated, details of osteoderm development along a size gradient remain less well‐known. Likewise, a comparative survey of additional species within the broaderGekkoclade to determine the uniqueness of this trait has not yet been completed. Here, we studied a large sample of gekkotans (38 spp.), including 18 specimens ofG. gecko, using X‐rays and high‐resolution computed tomography for visualizing and quantifying the dermal armorin situ. Results from this survey confirm the presence of osteoderms in a second species within this genus,GekkoreevesiiGRAY 1831, which exhibits discordance in timing and pattern of osteoderm development when compared with its sister taxon,G. gecko. We discuss the developmental sequence of osteoderms in these two species and explore in detail the formation and functionality of these enigmatic dermal ossifications. Finally, we conducted a comparative analysis of endolymphatic sacs in a wide array of gekkotans to explore previous ideas regarding the role of osteoderms as calcium reservoirs. We found thatG. geckoand other gecko species with osteoderms have highly enlarged endolymphatic sacs relative to their body size, when compared to species without osteoderms, which implies that these membranous structures might fulfill a major role of calcium storage even in species with osteoderms.

    

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5. HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization

   https://doi.org/10.3847/1538-4357/ac2ffc  

   Abdurashidova, Zara ; Aguirre, James E. ; Alexander, Paul ; Ali, Zaki S. ; Balfour, Yanga ; Barkana, Rennan ; Beardsley, Adam P. ; Bernardi, Gianni ; Billings, Tashalee S. ; Bowman, Judd D. ; et al ( January 2022 , The Astrophysical Journal)

   Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations atz∼ 8 and 10. Here, we use several independent theoretical models to infer constraints on the intergalactic medium (IGM) and galaxies during the epoch of reionization from these limits. We find that the IGM must have been heated above the adiabatic-cooling threshold byz∼ 8, independent of uncertainties about IGM ionization and the radio background. Combining HERA limits with complementary observations constrains the spin temperature of thez∼ 8 neutral IGM to 27 K$〈{\overline{T}}_S〉$630 K (2.3 K$〈{\overline{T}}_S〉$640 K) at 68% (95%) confidence. They therefore also place a lower bound on X-ray heating, a previously unconstrained aspects of early galaxies. For example, if the cosmic microwave background dominates thez∼ 8 radio background, the new HERA limits imply that the first galaxies produced X-rays more efficiently than local ones. Thez∼ 10 limits require even earlier heating if dark-matter interactions cool the hydrogen gas. If an extra radio background is produced by galaxies, we rule out (at 95% confidence) the combination of high radio and low X-ray luminosities ofL_r,ν/SFR > 4 × 10²⁴W Hz⁻¹$M_{\odot }^{-1}$yr andL_X/SFR < 7.6 × 10³⁹erg s⁻¹$M_{\odot }^{-1}$yr. The new HERA upper limits neither support nor disfavor a cosmological interpretation of the recent Experiment to Detect the Global EOR Signature (EDGES) measurement. The framework described here provides a foundation for the interpretation of future HERA results.

    

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