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We analyze the cool gas in and around 14 nearby galaxies (atz< 0.1) mapped with the Sloan Digital Sky Survey IV MaNGA survey by measuring absorption lines produced by gas in spectra of background quasars/active galactic nuclei at impact parameters of 0–25 effective radii from the galactic centers. Using Hubble Space Telescope/Cosmic Origins Spectrograph, we detect absorption at the galactic redshift and measure or constrain column densities of neutral (Hi, Ni, Oi, and Ari), low-ionization (Siii, Sii, Cii, Nii, and Feii), and high-ionization (Siiii, Feiii, Nv, and Ovi) species for 11 galaxies. We derive the ionization parameter and ionization-corrected metallicity usingcloudyphotoionization models. The Hicolumn density ranges from ∼10¹³to ∼10²⁰cm⁻²and decreases with impact parameter forr≳R_e. Galaxies with higher stellar mass have weaker Hiabsorption. Comparing absorption velocities with MaNGA radial velocity maps of ionized gas line emissions in galactic disks, we find that the neutral gas seen in absorption corotates with the disk out to ∼10R_e. Sight lines with lower elevation angles show lower metallicities, consistent with the metallicity gradient in the disk derived from MaNGA maps. Higher-elevation angle sight lines show higher ionization, lower Hicolumn density, supersolar metallicity, and velocities consistent with the direction of galactic outflow. Our data offer the first detailed comparisons of circumgalactic medium (CGM) properties (kinematics and metallicity) with extrapolations of detailed galaxy maps from integral field spectroscopy; similar studies for larger samples are needed to more fully understand how galaxies interact with their CGM.

 

We present measurements of the dependence of the clustering amplitude of galaxies on their star formation rate (SFR) and stellar mass (M*) at 0.7 < z < 1.5 to assess the extent to which environment affects these properties. While these relations are well determined in the local Universe, they are much more poorly known at earlier times. For this analysis, we make use of the near-infrared HST WFC3 grism spectroscopic data in the five CANDELS fields obtained as part of the 3D-HST survey. We make projected two-point correlation function measurements using ∼6000 galaxies with accurate redshifts, M*, and H α luminosities. We find a strong dependence of clustering amplitude on H α luminosity and thus SFR. However, at fixed M*, the clustering dependence on H α luminosity is largely eliminated. We model the clustering of these galaxies within the halo occupation distribution framework using the conditional luminosity function model and the newly developed conditional stellar mass and H α luminosity distribution model. These show that galaxies with higher SFRs tend to live in higher mass haloes, but this is largely driven by the relationship between SFR and M*. Finally, we show that the small residual correlation between clustering amplitude and H α luminosity at fixed M* is likely being driven by a broadening of the SFR–M* relationship for satellite galaxies.

 

Emerging infectious diseases have been especially devastating to amphibians, the most endangered class of vertebrates. For amphibians, the greatest disease threat is chytridiomycosis, caused by one of two chytridiomycete fungal pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans ( Bsal ). Research over the last two decades has shown that susceptibility to this disease varies greatly with respect to a suite of host and pathogen factors such as phylogeny, geography (including abiotic factors), host community composition, and historical exposure to pathogens; yet, despite a growing body of research, a comprehensive understanding of global chytridiomycosis incidence remains elusive. In a large collaborative effort, Bd -Maps was launched in 2007 to increase multidisciplinary investigations and understanding using compiled global Bd occurrence data ( Bsal was not discovered until 2013). As its database functions aged and became unsustainable, we sought to address critical needs utilizing new technologies to meet the challenges of aggregating data to facilitate research on both Bd and Bsal . Here, we introduce an advanced central online repository to archive, aggregate, and share Bd and Bsal data collected from around the world. The Amphibian Disease Portal ( https://amphibiandisease.org ) addresses several critical community needs while also helping to build basic biological knowledge of chytridiomycosis. This portal could be useful for other amphibian diseases and could also be replicated for uses with other wildlife diseases. We show how the Amphibian Disease Portal provides: (1) a new repository for the legacy Bd- Maps data; (2) a repository for sample-level data to archive datasets and host published data with permanent DOIs; (3) a flexible framework to adapt to advances in field, laboratory, and informatics technologies; and (4) a global aggregation of Bd and Bsal infection data to enable and accelerate research and conservation. The new framework for this project is built using biodiversity informatics best practices and metadata standards to ensure scientific reproducibility and linkages across other biological and biodiversity repositories. 

The genus Chiropterotriton is endemic to Mexico with a geographical distribution along the Sierra Madre Oriental, the Trans Mexican Volcanic Belt and the Sierra de Juárez. The recent use of molecular tools has shown that Mexico’s amphibian diversity is highly underestimated, including a large number of cryptic, unnamed species. Chiropterotriton has 18 described species including terrestrial, arboreal and cave-dwelling species. In previous molecular studies, the presence of multiple undescribed species was evident. We present a phylogenetic hypothesis based on mitochondrial data, which includes all described species and six undescribed taxa. Based on the morphological analyses and, when available, combined with molecular data, we describe five new species of the genus; Chiropterotriton casasi sp. nov., C. ceronorum sp. nov., C. melipona sp. nov., C. perotensis sp. nov. and C. totonacus sp. nov. In addition, we redescribe two others: Chiropterotriton chiropterus and C. orculus , and provide a comparable account of one additional sympatric congener. This increases the number of species in the genus to 23, which represent a considerable component of Mexican plethodontid richness. 

We describe three new species of minute salamanders, genusThorius, from the Sierra Madre del Sur of Oaxaca, Mexico. Until now only a single species,T. minutissimus, has been reported from this region, although molecular data have long shown extensive genetic differentiation among geographically disjunct populations. AdultThorius pinicolasp. nov.,T. longicaudussp. nov., andT. tlaxiacussp. nov. are larger thanT. minutissimusand possess elliptical rather than oval nostrils;T. pinicolaandT. longicaudusalso have longer tails. All three new species occur west of the range ofT. minutissimus, which has the easternmost distribution of any member of the genus. The new species are distinguished from each other and from other namedThoriusin Oaxaca by a combination of adult body size, external morphology and osteology, and by protein characters (allozymes) and differences in DNA sequences. In addition, we redescribeT. minutissimusand a related species,T. narisovalis, to further clarify the taxonomic status of Oaxacan populations and to facilitate future studies of the remaining genetically differentiatedThoriusthat cannot be satisfactorily assigned to any named species. Populations of all five species considered here appear to have declined dramatically over the last one or two decades and live specimens are difficult to find in nature.Thoriusmay be the most endangered genus of amphibians in the world. All species may go extinct before the end of this century.

 

Abstract This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated value-added catalogs. This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper, Local Volume Mapper, and Black Hole Mapper surveys.