2,334 research outputs found
The Gobiid Fish Palatogobius paradoxus in the Northern Gulf of Mexico
Fourteen specimens of the little known gobiid fish Palatogobius paradoxus, recently collected from the northern Gulf of Mexico, have added significantly to our knowledge of the species. Morphometric and meristic characters of these specimens agree closely with two of the other three known specimens, taken from the Virgin Islands and Venezuela, and are thus considered conspecific. The third previously collected specimen, taken from Panama, shows variation in vomerine teeth and fin ray characters, and thus its specific status is unresolved. Data from these additional specimens indicate less intraspecific variation in some characters than was apparent from the original three specimens
Provenance and Disposition of Fish Specimens Appearing in Color Plates of Kuehne and Barbour\u27s Book, \u3cem\u3eThe American Darters\u3c/em\u3e
Two New Western Atlantic Species of the Gobiid Fish Genus Gobionellus, with Remarks on Characteristics of the Genus
Two new western Atlantic species of Gobionellus (family Gobiidae) are described and figured. G. comma, which is presently known only from the southern Caribbean Sea, off Venezuela, is characterized primarily by a dark, comma-shaped bar in the suborbital area. G. atripinnis, which has been found only in the western Gulf of Mexico, from southern Texas to Veracruz, Mexico, is most readily distinguished by an elongate black blotch in the male\u27s spinous dorsal fin and in having 16 pectoral fin rays. G. comma is closely related to the eastern Pacific G. manglicola. The relationships of G. atripinnis are more obscure.
Important diagnostic characters of Gobionellus are presented, together with preliminary conclusions concerning the interrelationships of the genera Evorthodus and Oxyurichthys, which closely resemble Gobionellus in several important ways. Although groundwork is laid for possible synonymization of these genera (including discussion of nomenclatural problems), such action is deferred until more comprehensive studies are completed.
A total of 14 coarse-scaled species of Gobionellus are recognized. These are included in a taxonomic key, which also includes a geographic range statement for each species. Also included in the key are the two species of Evorthodus, which are frequently confused with the coarse-scaled Gobionellus. This key does not include the recently-described G. munizi Vergara 1978, specimens of which we have not had the opportunity to examine. Comments are included, however, regarding this species\u27 validity and probable relationships, based on text of the original description and accompanying figures
Additional Information on the Gobiid Fish Varicus imswe, with Comments on the Nominal Species of Varicus
A Prograde, Low-Inclination Orbit for the Very Hot Jupiter WASP-3b
We present new spectroscopic and photometric observations of the transiting
exoplanetary system WASP-3. Spectra obtained during two separate transits
exhibit the Rossiter-McLaughlin (RM) effect and allow us to estimate the
sky-projected angle between the planetary orbital axis and the stellar rotation
axis, lambda = 3.3^{+2.5}_{-4.4} degrees. This alignment between the axes
suggests that WASP-3b has a low orbital inclination relative to the equatorial
plane of its parent star. During our first night of spectroscopic measurements,
we observed an unexpected redshift briefly exceeding the expected sum of the
orbital and RM velocities by 140 m/s. This anomaly could represent the
occultation of material erupting from the stellar photosphere, although it is
more likely to be an artifact caused by moonlight scattered into the
spectrograph.Comment: 23 pages, 4 figures, Accepted for publication in The Astrophysical
Journal, Replacement includes revised citation
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Widespread supplementary feeding in domestic gardens explains the return of reintroduced Red Kites Milvus milvus to an urban area
Reintroductions are used worldwide to mitigate biodiversity loss. One prominent case is a charismatic raptor of conservation concern, the Red Kite Milvus milvus. This species has been reintroduced across the UK over the last 25 years following its near extinction after centuries of persecution. The species was not expected to recolonize urban areas; its historical association with human settlements is attributed to scavenging on human waste and refuse, a resource now greatly reduced on the streets of modern Western cities. However, the species has become a common day-time visitor to a large conurbation centred on the town of Reading, southern England, approximately 20 km from the first English reintroduction site. Given a near-absence of breeding and roost sites, we investigated foraging opportunities and habitat associations that might explain use by Red Kites of this urban area. Surveys of discarded human foods and road-kill suggested that these could support at most 13−29 kites/day. Face-to-face surveys of a cross-section of residents revealed that 4.5% (equivalent to 4349 households) provided supplementary food for kites. Using estimates of per-household resource provision from another study, we calculated that this level is potentially sufficient to provision 142−320 kites, a substantial proportion of the total estimated to visit the conurbation each day (between 140 and 440). Road transects found positive associations between Red Kites and residential areas. We therefore suggest that the decision made by thousands of individuals to provide supplementary food for Red Kites is the primary factor explaining their day-time abundance in this urban area
Are Textures Natural?
We make the simple observation that, because of global symmetry violating
higher-dimension operators expected to be induced by Planck-scale physics,
textures are generically much too short-lived to be of use for large-scale
structure formation.Comment: 9p
Fishes of the Choctawhatchee River System in Southeastern Alabama and Northcentral Florida
The diversity and distribution of fish species occurring in the Choctawhatchee River drainage in southeastern Alabama and northcentral Florida were surveyed to obtain historical baseline information. Three hundred seventy-four sites were evaluated for species diversity and distribution in the drainage, including compilation of unpublished records from southeastern natural history museums. The greatest diversity at any single site was 37 species. Sixty-eight sites were represented by 15 species or more, and 26 sites were represented by a single species. The most frequently encountered species includes Gambusia holbrooki, Percina nigrofasciata, Esox americanus, Notropis texanus, Lepomis macrochirus, Cyprinella n. sp. cf venusta, Notropis amplamala, and Aphredoderus sayanus. New records for Hybopsis n. sp. cf winchelli and Etheostoma parvipinne were found in the drainage, and range extensions were found for 14 other species. Our study increases the known number of fish species in the Choctawhatchee River drainage to 132 species and two hybrids, including 83 native freshwater, 10 introduced freshwater, 24 estuarine, and 17 marine species
Qatar-2: A K dwarf orbited by a transiting hot Jupiter and a more massive companion in an outer orbit
We report the discovery and initial characterization of Qatar-2b, a hot
Jupiter transiting a V = 13.3 mag K dwarf in a circular orbit with a short
period, P_ b = 1.34 days. The mass and radius of Qatar-2b are M_p = 2.49 M_j
and R_p = 1.14 R_j, respectively. Radial-velocity monitoring of Qatar-2 over a
span of 153 days revealed the presence of a second companion in an outer orbit.
The Systemic Console yielded plausible orbits for the outer companion, with
periods on the order of a year and a companion mass of at least several M_j.
Thus Qatar-2 joins the short but growing list of systems with a transiting hot
Jupiter and an outer companion with a much longer period. This system
architecture is in sharp contrast to that found by Kepler for multi-transiting
systems, which are dominated by objects smaller than Neptune, usually with
tightly spaced orbits that must be nearly coplanar
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