Mesembrioxylon obscurum , a new combination for Araucarioxylon? obscurum Knowlton, from the Upper Jurassic Morrison Formation, Wyoming

A reinvestigation of the type specimen of Araucarioxylon? obscurum Knowlton (1900) from the Upper Jurassic Morrison Formation in the Freezeout Hills of Wyoming has determined that this fossil should be transferred to Mesembrioxylon Seward (1919) as M. obscurum comb. nov. (Knowlton) Medlyn and Tidwell. Knowlton (1900), who was uncertain of its appropriate generic disposition, tentatively referred the wood to Araucarioxylon because it had obscure growth rings and relatively low ray height. Reexamination of Knowltons slides demonstrates that the wood has uniseriate, rarely biseriate rays, podocarpoid pitting, and diffuse axial parenchyma, none of which Knowlton mentioned. Tracheary pitting is mostly separate, round, uniseriate, occasionally biseriate and, when biseriate, opposite to subopposite. The smooth-walled crossfields exhibit 1-3 thin-bordered podocarpaceous pits per field. All of these features are present in Mesembrioxylon Seward.     

Flora of the Lower Cretaceous Cedar Mountain Formation of Utah and Colorado, part I. Paraphyllanthoxylon utahense

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Paraphyllanthoxylon utahense, sp. nov., is described from the Cedar Mountain Formation and compared with similar fossil and modern woods. Fossil angiosperm woods from the Early Cretaceous are of great interest because very few have been reported from strata of this age. This species demonstrates that the angiosperms had developed many of their modern characteristics by Early Cretaceous time.     

Hindia sphaeroidalis Duncan from the Devonian of Nevada (Porifera)

The small, spherical, lithistid sponge, Hindia sphaeroidalis Duncan, 1879, is reported from the Devonian and Silurian of the Great Basin for the first time. Devonian specimens came from the Emsian Bartine Member of the McColley Formation from near Roberts Creek, Roberts Mountains, and from the Eifelian part of the Nevada Group near Bishops Creek, north of Wells, Nevada. The Silurian occurrence, questioned because of poor preservation, is from the Laketown Dolomite, on Tunnel Spring Mountain in western Millard County, Utah.     

A new genus and species of Cixiidae (Homoptera: Fulgoroidea) from Lower Cretaceous amber

Mundopoides aptianus gen. et sp. nov. (Homoptera: Fulgoroidea: Cixiidae) is described on the basis of a fossil of an adult female preserved in Lebanese amber of Lower Cretaceous (Aptian) age, and is compared with modern genera.     

Full-glacial shoreline vegetation during the maximum highstand at Owens Lake, California

Owens Valley, California, was markedly different during the Wisconsin glacial stage from what it is today. Alpine glaciers bounded the Sierra Nevada, and pluvial Owens Lake reached highstands and overflowed its natural basin. We analyzed three layers from two packrat middens, dated to ca 23,000-14,500 yr BP, obtained from Haystack Mountain (1155 m) only 10 m above and Juniperus osteosperma ) and single-needle pinyon pine ( Pinus monophylla ) woodland existed at the site. In the layers dated to ca 17,500 and 16,000 yr BP, macrofossils document the presence of Rocky Mountain juniper ( Juniperus scopulorum ), a species that no longer occurs in California. It is suggested that meltwater from the retreating glacial ice inundated the Owens River Lake chain causing pluvial Owens Lake to reach its highstand. This caused an increase in effective moisture, due to high groundwater, allowing the mesophytic Rocky Mountain juniper to exist at the site.     

Evaluating the use of morphometric measurements from museum specimens for sex determination in Mountain Plovers ( Charadrius montanus )

The Mountain Plover ( Charadrius montanus ) is a shorebird species endemic to the dry, terrestrial ecosystems of the Great Plains and southwestern United States. Breeding Bird Survey data suggest that Mountain Plover populations have declined by > 60% in the last 30 years. A better understanding of the population dynamics of the Mountain Plover is important in determining future management goals for this species. However, this effort is hampered by the inability to determine the sex of Mountain Plovers accurately under field conditions. In an effort to develop a simple method for sexing plovers in the hand, we measured external morphometric characteristics from 190 museum specimens of adult Mountain Plovers in alternate (breeding) plumage. Logistic regression and discriminant function analyses were performed on 10 external morphometric measurements (lengths of unflattened wing chord, 10th primary, central rectrix, outer rectrix, total head length, exposed culmen, culmen, bill depth, bill width, and tarsus). The results of these analyses indicated that Mountain Plover sexes were similar for all measures except culmen length. However, further analysis determined that culmen length accurately predicted sex in less than two-thirds of the specimens, suggesting that this measure is a poor predictor of sex in Mountain Plovers. Structurally, Mountain Plovers appear to be nearly identical between the sexes, and other methods of sexing birds (e.g., plumage characteristics, behavioral observations, or molecular markers) should be further assessed for devising a simple method for sexing Mountain Plovers under field conditions.     

Habitat requirements for Erigeron kachinensis , a rare endemic of the Colorado Plateau

Erigeron kachinensis is a rare endemic of the Colorado Plateau in southeastern Utah. This perennial composite grows in small, isolated populations at seeps and alcoves arising along canyon walls in Cedar Mesa Sandstone substrates. Characteristics of six Erigeron kachinensis sites in Natural Bridges National Monument, San Juan County, Utah, were studied to determine habitat requirements for this species. Sites were analyzed with respect to geology, soil chemistry, physical properties, and vegetational characteristics. The alcoves studied were very saline, often with soil surfaces covered with a white crust of salt. Living cover was enhanced by perennially moist soils, diminished amounts of solar radiation, soil salinity, and above-average amounts of available soil phosphorus. Kachina daisy vegetative growth appears to be favored by these same abiotic factors. The most commonly associated plant species on E. kachinensis sites were Aquilegia micrantha, Calamagrostis scopulorum, Zigadenus vaginatus, and Erigeron kachinensis . These species and the daisy accounted for more than 75% of the total living cover in the alcoves studied. A principal components analysis procedure was developed for evaluating site suitability for Erigeron kachinensis . This daisy has been successfully introduced to a site selected using that model.     

Breeding biology of Mountain Plovers ( Charadrius montanus ) in the Uinta Basin

The known Mountain Plover population breeding on the Myton Bench, Duchesne County, Utah, is small, composed roughly of 30 adults and young after each breeding season. Currently, its location is peripheral to the species main range. This shrub-steppe breeding habitat differs from the shortgrass prairie habitat with which this bird is historically associated. Between 1996 and 1998 we made observations at nesting sites located consistently in 2 concentrated areas surrounded by large tracts of similar habitat. Activity may be focused in these specific areas because of breeding-site fidelity; this behavior is common among most shorebirds and has been documented for the Mountain Plover in Colorado. Also, Mountain Plovers are social and tend to choose nest sites near others. Most nests in Utah were located within close proximity of mounds of white-tailed prairie dogs ( Cynomys leucurus ), and all were situated near roadways or oil well pads. Mountain Plovers were often observed with broods on these bare areas at night. We conclude that Mountain Plovers on the Myton Bench are distributed in clumped breeding colonies within large areas of apparently favorable habitat.     

Survival rates of translocated and native Mountain Quail in Oregon

We estimated survival rates for 232 radio-tagged native ( n = 157) and translocated ( n = 75) Mountain Quail ( Oreortyx pictus ) from 1997 to 1999 in Hells Canyon National Recreation Area (HCNRA) in northeastern Oregon and in the Cascade Mountain Range (CMR) of southwestern Oregon. For the combined areas the estimated survival rate during 150-day intervals was 0.42 ± 0.04. Estimated survival was 0.41 ± 0.04 for Mountain Quail in HCNRA and 0.34 ± 0.34 for quail in CMR. There were no differences in survival functions for native quail in HCNRA and CMR ( P = 0.91), for translocated and native quail in HCNRA ( P = 0.93), for native quail in CMR and translocated quail in HCNRA ( P = 0.97), or for birds released in the fall and birds released in the winter ( P = 0.57). Male and female survival functions were significantly different ( X 2 1 = 4.61, P = 0.02). The estimated risk ratio for males was 0.66 that of females. Translocated wild Mountain Quail appeared to have survival rates similar to native quail. Mountain Quail experienced mortalities of > 50% over a 150-day interval in both the conifer forests of the western Cascade Mountain Range and the semiarid habitats of northeastern Oregon. With the ability to rapidly expand their populations and exploit marginal habitats, Mountain Quail are excellent candidates for reintroduction programs, and translocated wild Mountain Quail could be used to supplement declining populations.     

Nest site selection by Mountain Plovers ( Charadrius montanus ) in a shrub-steppe habitat

The known Mountain Plover population breeding on the Myton Bench, Duchesne County, Utah, is small, composed roughly of 30 adults and young after each breeding season. Currently, its location is peripheral to the species main range. This shrub-steppe breeding habitat differs from the shortgrass prairie habitat with which this bird is historically associated. Between 1996 and 1998 we made observations at nesting sites located consistently in 2 concentrated areas surrounded by large tracts of similar habitat. Activity may be focused in these specific areas because of breeding-site fidelity; this behavior is common among most shorebirds and has been documented for the Mountain Plover in Colorado. Also, Mountain Plovers are social and tend to choose nest sites near others. Most nests in Utah were located within close proximity of mounds of white-tailed prairie dogs ( Cynomys leucurus ), and all were situated near roadways or oil well pads. Mountain Plovers were often observed with broods on these bare areas at night. We conclude that Mountain Plovers on the Myton Bench are distributed in clumped breeding colonies within large areas of apparently favorable habitat.     

Four new species of Pauropodidae (Myriapoda: Pauropoda) from Zhejiang and Jiangsu Provinces,east China

Four new species of the family Pauropodidae are described from East China: Allopauropus lasiochlamis sp. nov. and Donzelotauropus lanceus sp. nov. from Tianmu Mountain, Zhejiang Province, and Allopauropus tetrachotomous sp. nov. and Allopauropus tristylus sp. nov. from Qixia Mountain, Jiangsu Province.     

Agathoxylon lemonii sp. nov., from the Dakota Formation, Utah

Petrified wood specimens from the Dakota Formation of Utah are here described as Agathoxylon lemonii . This new species is characterized by having distinct growth rings, araucarian tracheary pitting, resin plates or plugs in its tracheids, abundant axial parenchyma, low uniseriate rays and 1–4 small, slightly bordered pits with circular to oval included apertures per crossfield. This is the first report of petrified wood from the Dakota Formation of the western United States and the first record of Agathoxylon from North America.     

Montane insular butterfly biogeography: fauna of Ball Mountain, Siskiyou County, California

Ball Mountain is an isolated, mostly heavily forested peak reaching the subalpine zone (2,330 m) in eastern Siskiyou County north of Mt. Shasta, California. It supports a rich fauna of at least 68 butterfly species showing affinities to the faunas of the Trinity Alps and Eddies, the Warners, and the Cascades. Rare or endemic entities include Speyeria monnonia, Lycaena heteronea gravenotata , and melanic forms of Speyeria atlantis and Agriades ";glandon."; Several zones of intergradation or hybridization impinge on the fauna as well.     

Diatom flora of Mink Creek, Idaho, USA

Diatoms were collected from an open-canopy and closed-canopy site on Mink Creek, Bannock County, Idaho, a third-order Rocky Mountain stream. Ninety diatom taxa were identified. Achnanthes minutissima Kuetz. And Navicula lanceolata (Ag. ) Kuetz. dominated the open-canopy site, whereas Cocconeis placentula var. euglypta (Ehr.)CI. comprised greater than 40% of the diatom assemblage at the closed-canopy site. Seven of the 10 most important diatoms were present at both sites. A high degree of similarity was evident between natural and artificial substrates at both sites. Although most taxa were present at both sites, it is apparent from this study that differences in the abundance of taxa occur according to variations in light.     

An undescribed species of Thelypodiopsis (Brassicaceae) from the Uinta Basin, Utah

Thelypodiopsis argillacea Welsh and Atwood sp. nov. is described from specimens collected on the Green River Shale Formation in Uintah County, Utah.     

Nesting phenology and productivity of birds in the White and Inyo Mountains, California, as assessed with nest-boxes

Nest-boxes were monitored from 1988 to 1992 on 5 grids in the pinyon-juniper ( Pinus-Juniperus ) woodlands of the White and Inyo Mountains, California, to determine breeding phenology and productivity of cavity-nesting birds, and characteristics of used and non-used nest-boxes. We found a total of 112 nests of 6 species. Bewicks Wrens ( Thryomanes bewicki i; 64 nests), Mountain Chickadees ( Poecile gambeli ; 18), Ash-throated Flycatchers ( Myiarchus cinerascens ; 12), and Juniper Titmice ( Baeolophus ridgwayi ; 11) were the most common species utilizing the boxes. Nest phenology and numbers of young were similar to values reported elsewhere in the literature for the species, although nesting success for Mountain Chickadees appeared lower in our study. Chickadees were associated with relatively dense, mature vegetation on southern slopes. Juniper Titmice used areas with tall juniper shrubs and generally sparse vegetation. Bewicks Wrens used areas with short trees, sparse vegetation, and many stumps. Nest-boxes were underutilized (< 15% use) by most species relative to their availability and relative to detected abundances of the species. We suggest that nest-boxes can provide valuable breeding biology information and can potentially increase the productivity of rare and cavity-limited species.     

Model of breeding habitat of the Mountain Plover ( Charadrius montanus ) in western Wyoming

To aid the conservation and management of Mountain Plovers ( Charadrius montanus ), we developed a spatially explicit model of breeding habitat for the shrub-steppe of western Wyoming. Points of Mountain Plover presence and absence were determined by field surveys conducted May through June 1999. At each point we measured topographic slope and a cover type suitability index related to vegetation height and density. Logistic regression revealed a strong negative relationship between presence and slope, and a weaker and positive relationship between presence and cover index. A multiple logistic regression model using slope and cover index to predict presence successfully classified 87% of the points in an independent data set covering much of western Wyoming. The spatial expression of this model will help managers target future surveys and identify currently unsuitable habitat that could be improved via vegetation management. Patches of suitable breeding habitat of the Mountain Plover in western Wyoming are probably functions of poor soil, low precipitation, and wind scour, and thus are likely rather persistent in space and time. Combined with the relatively large proportion of publicly owned land here, this may make conservation and recovery of the Mountain Plover easier in western Wyoming than in the more dynamic and privately controlled Great Plains.     

Distribution and abundance of birds in the White Mountains, California

This paper quantifies the distribution and abundance of birds in the White Mountains, Inyo and Mono counties, California, during spring-summer 1989-91, to establish a baseline for monitoring the area's avifauna. Overall 58 species were encountered in the single-leaf pinyon-Utah juniper ( Pinus monophylla-Juniperus osteosperma ) zone, and 61 species in the bristlecone-limber pine ( P. longaeva-P. flexilis ) zone. The bristlecone-limber pine zone had a significantly greater overall bird abundance relative to the pinyon-juniper. Both zones were characterized by few very abundant species, a few moderately abundant species, and numerous rare species. The Black-throated Gray Warbler (scientific names in tables), Gray Flycatcher, and Pinyon Jay were the most abundant species in the pinyon-juniper whereas the Clark's Nutcracker, Mountain Chickadee, and Cassin's Finch were the most abundant species in the bristlecone-limber pine. There were few ecological or taxonomic replacements of species between zones, with the differences in distribution and abundance related primarily to the interaction between elevation and vegetation. Significant inter-year variation in abundance was found for about 20 species in each zone—more species showed declining rather than increasing trends. The Mountain Chickadee and White-breasted Nuthatch declined, whereas the Gray Flycatcher and Rock Wren increased across years in both zones. Reasons for declines in some species might be the severe drought that continued throughout this study.