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1.
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.  相似文献   

2.
Named and described is Astragalus piscator Barneby & Welsh, a species of sect. Argophylli subsect. Missourienses. The species occurs in Grand and San Juan counties, Utah.      相似文献   

3.
Management decisions affecting the rare plant Arizona willow ( Salix arizonica ) will be aided by understanding genetic similarities among populations of this species. Random Amplified Polymorphic DNA (RAPD) analysis was conducted on 20 populations of S. arizonica , 12 populations of 5 congeners, and 2 samples of outgroup, Populus tremuloides . A phenogram based on DNA markers shows clear separation of populations of S. arizonica from those of co-occurring willow species, but similarity is low (~ 37%) between Utah and Arizona populations of S. arizonica . Evaluation of the relationship of habitat characteristics and geographic distance to genetic similarity reveals that environment and genetic similarity are poorly correlated. Considering Arizona versus Utah populations, we found a significant negative relationship between geographic distance and genetic similarity ( r = 0.936), but no significant relationship between interpopulation distance and genetic similarity within Arizona or Utah. The wide geographic disjunction of S. arizonica populations in Utah and Arizona appears to have existed for a long period during which genetic drift, random mutations, and selection for somewhat different habitats have pushed the 2 regional complexes along separate evolutionary trajectories. Preservation of genetic variation within S. arizonica will require protection of multiple populations in Arizona and Utah.  相似文献   

4.
Named as a new species from the House Range of Millard County, Utah, as Primula domensis Kass & Welsh.  相似文献   

5.
New species of Mentzelia and Phacelia are described from northwestern New Mexico, USA, as Mentzelia todiltoensis , N. Duane Atwood & Stanley L. Welsh, and Phacelia sivinskii N. D. Atwood, sp. nov. The new Mentzelia is compared to M. humilis based on similarities in seed, fruit, leaf, and flower morphology and to M. memorabalis in stem, leaf, and fruit morphology. Phacelia sivinskii is compared to P. constancei N. D. Atwood on the basis of seed, leaf, and flower morphology.  相似文献   

6.
We examined the effect of elevation on litter-size variation in viviparous lizards of the Sceloporus grammicus complex in 10 states of Mexico. Female snout–vent length (SVL) decreased with increasing elevation, and absolute litter size based on embryos also tended to de crease with increasing elevation. However, after controlling for variation in female body size, we found that litter sizes tended to be relatively larger at higher elevation. Elevation therefore appears to influence litter size in these lizards; however, relatively little of the variation is explained by elevation; thus, other factors are likely making substantial contributions to the observed litter-size variation. The S. grammicus complex appears to be a good model system for examining the underlying causes of geographic and elevational variation in lizard life histories. Examinamos el efecto del altitud en la variación del tamaño de camada de las lagartijas vivíparas del complejo Sceloporus grammicus en 10 estados de México. La LHC de las hembras disminuyó con la altitud, y el tamaño absoluto de camada, calculado con base en el número de embriones, también tendió a disminuir. No obstante, después de controlar la variación en el tamaño corporal de las hembras, encontramos que los tamaños de camada tendieron a ser relativamente más grandes en altitudes mayores. La altitud, por tanto, parece influir en el tamaño de camada de estas lagartijas; sin embargo, la altitud explica relativamente poco de la variación, por lo que, es probable que otros factores contribuyan substancialmente a la variación observada en el tamaño de camada. El complejo S. grammicus parece ser un buen sistema para estudiar las causas fundamentales de la variación geográfica y altitudinal en la historia de vida de las lagartijas.  相似文献   

7.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* 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;} Named as new species are Hymenoxys lapidicola Welsh & Neese, from Uintah County, Utah, and Perityle specuicola Welsh & Neese, from Grand County, Utah.  相似文献   

8.
Distributional records are given for 40 stonefly species on 15 isolated mountain ranges in Nevada and Utah.  相似文献   

9.
A bulk sampling of gastropods collected near Great Salt Lake, Utah, Revealed several fish bones of Gila atraria (Girard). The early date of this find, coupled with the relationship of the Gilbert lake transgression and successive regression of approximately 11,000 years B.P., reveals a death assemblage induced by a series of saline inundations into the freshwater paludal environment.  相似文献   

10.
Yucca harrimaniae var. sterilis Neese & Welsh is named and described from the Uinta Basin of Utah. The plant is strongly rhizomatous, evidently sterile, and has limber, sparingly filiferous leaves that tend to recline on the ground.      相似文献   

11.
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;} Named as new is Stephanomeria tenuifolia (Torr.) Hall var. uintaensis Goodrich & Welsh.  相似文献   

12.
Named is Mentzelia pumila (Nutt.) T. &: G. var. lagarosa Thorne var. nov. from Utah.  相似文献   

13.
Trichodina tenuiformis Stein, 1979 and Apiosoma campanulactum Timofeev, 1962 were found on gills of mottled sculpin ( Cottus bairdi ) from two locations in the Provo River, UT. They were studied by light and electron optics. Dimensions and morphology of the adhesive disc and denticles of T. tenuiformis were differentiated from other Trichodina species. A. campanulatum was characterized by its spindle-shaped cell body. Fine features examined by scanning electron microscopy included body shape, pellicle, elements of the adhesive disc, aboral ciliary complex, and aboral ciliary spiral. Histopathological studies suggested that the organisms are ectocommensals. Ecological aspects of organism infestation between two areas were also investigated. This report establishes a new host and distribution record for these two species in mottled sculpin from the Provo River, UT.  相似文献   

14.
New taxa include: Cryptantha cinerea (Torr.) Cronq. var. arenicola Higgins & Welsh; Physaria chambersii Rollins var. sobolifera Welsh (Cruciferae); Phacelia demissa Gray var. minor N. D. Atwood (Hydrophyllaceae); Iris pariensis Welsh (Iridaceae); Astragalus preussii var. cutleri Barneby and Pediomelum aromaticum (Payson) Welsh var. tuhyi Welsh (Leguminosae); Abronia nana Wats. var. harrisii Welsh (Nyctaginaceae); Camissonia atwoodii Cronq. (Onagraceae); Habenaria zothecina Higgins & Welsh (Orchidaceae); Aqiiilegia formosa Fisch. in DC. var. fosteri Welsh (Ranunculaceae). New nomenclatural combinations include: Rhus aromatica Ait. var. simplicifolia (Greene) Cronq. (Anacardiaceae); Lomatium kingii (Wats.) Cronq., L. kingii var. alpinum (Wats.) Cronq. (Apiaceae); Cryptantha cinerea (Torr.) Cronq. var. laxa (Macbr.) Higgins; Mertensia lanceolata (Pursh) DC. var. nivalis (Wats.) Higgins (Boraginaceae); Opuntia erinacea Engelm. var. aurea (Baxter) Welsh (Cactaceae); Arenaria fendleri Gray var. aculeata (Wats.) Welsh, A. fendleri var. eastwoodiae (Rydb.) Welsh, Lychnis apetala L. var. kingii (Wats.) Welsh, Stellaria longipes Goldie var. monantha (Hulten) Welsh (Caryophyllaceae); Draba densifolia Nutt. ex T. & G. var. apiculata (C. L. Hitchc.) Welsh, D. oligosperma Hook. var. juniperina (Dorn) Welsh, Physaria acutifolia Rydb. var. stylosa (Rollins) Welsh, Thelypodiopsis sagittata (Nutt.) Schulz var. ovalifolia (Rydb.) Welsh (Cruciferae); Lotus plebeius (T. Brandg.) Barneby, Lupinus polyphyllus Lindl. in Edwards var. ammophilus (Greene) Barneby, L polyphyllus var. humicola (A. Nels.) Barneby, L. argenteus Pursh var. fulvomaculatus (Payson) Barneby, L. argenteus var. palmeri (Wats.) Barneby, Pediomelum aromaticum (Payson) Welsh, P. epipsilum (Barneby) Welsh, Psoralidium lanceolatum (Pursh) Rydb. var. stenophyllum (Rydb.) Welsh, and P. lanceolatum var. stenostachys (Rydb.) Welsh (Leguminosae); Mirabilis linearis (Pursh) Hiemerl var. decipiens (Standl.) Welsh (Nyctaginaceae); Camissonia boothii var. condensata (Munz) Cronq., C. boothii var. villosa (Wats.) Cronq., C. clavaeformis (Torr. & Frem.) Raven var. purpurascens (Wats.) Cronq., C. scapoidea (T. & G.) var. utahensis (Raven) Welsh, Oenothera caespitosa var. macroglottis (Rydb.) Cronq., Oe. caespitosa var. navajoensis (Wagner, Stockhouse, & Klein) Cronq., Oe. flava (A. Nels.) Garrett var. acutissima (W. L. Wagner) Welsh, and Oe. primiveris Gray var. bufonis (Jones) Cronq. (Onagraceae); Papaver radicatum Rottb. var. pygmaeum (Rydb.) Welsh (Papaveraceae); Dodecatheon pulchellum (Raf.) Merr. var. zionense (Eastw.) Welsh (Primulaceae); Aquilegia flavescens Wats. var. rubicunda (Tidestr.) Welsh, Delphinium andersonii Gray var. scaposum (Greene) Welsh, D. occidentalis (Wats.) Wats. var. barbeyi (Huth) Welsh, and Ranunculus andersonii Gray var. juniperinus (Jones) Welsh (Ranunculaceae); Purshia mexicana (D. Don) Welsh and P. mexicana var. stansburyi (Torr.) Welsh (Rosaceae); Galium mexicanum H.B.K. var. asperrimum (Gray) Higgins & Welsh (Rubiaceae); Castilleja parvula Rydb. var. revealii (N. Holmgren) N. D. Atwood and C. rhexifolia Rydb. var. sulphurea (Rydb.) N. D. Atwood (Scrophulariaceae).  相似文献   

15.
Twenty Catostomus latipinnis and 50 Catostomus discobolis from La Verkin Creek and the Fremont River in southern Utah were collected and surveyed for parasites. Data from the survey indicated that 83 percent of the fish were infected with at least one parasite, with the fish from La Verkin Creek harboring more parasites. Twelve genera and 12 species of parasites were identified from these fish. A monogenetic trematode, Gyrodactylus elegans, which was found in 90 percent of the fish, was the most common parasite. Comments are included on habitat and host variations for the parasitofauna from suckers taken from the two locations.  相似文献   

16.
In May 1974 four male spotted bats were netted near St. George, Utah. Contrary to published speculation on Euderma, indications are that the spotted bat in southwest Utah (1) is not a late flyer, (2) does not feed solely on moths, (3) may drop to the ground on occasion to forage, (4) is not a rapid flyer, and (5) appears to utilize crevices as roosting sites.    相似文献   

17.
Gilia tenuis Smith & Neese is a previously undescribed species from Emery and Sevier counties, Utah, apparently closely related to G. caespitosa Gray and G. subnuda Torr. ex Gray. It is distinguished from these species by its possession of a combination of characters including perennial, multicipital habit, lobed basal leaves, and small, pale blue flowers.  相似文献   

18.
Utah juniper ( Juniperus osteosperma ) has greatly expanded its historical range in the western United States. Management plans for the species have focused on curtailing its encroachment into sagebrush and grassland communities. These plans often include burning or other methods of elimination. These methods may result in subdivision or fragmentation of existing juniper stands. We initiated a study at Dugway Proving Ground, a U.S. Army facility, to examine the effects of fragmentation on the reproductive success of Utah juniper in isolated populations. We used enzyme electrophoresis to quantify genetic variability in isolated populations. We also determined population reproductive success by examining juniper fruits for evidence of seed abortion and/or presence of insect parasites. We compared reproductive and genetic variability in isolated populations at Dugway to 2 nonisolated and encroaching Utah juniper populations. The Dugway populations exhibited reduced seed set due to high seed abortion and/or insect seed parasitism, and a loss of genetic variability in comparison to the nonisolated populations. Additionally, there was a significant correlation between reproductive success and genetic variability.  相似文献   

19.
20.
Described is Mentzelia multicaulis (Osterh.) Goodman var. librina Thorne & F. J. Smith.  相似文献   

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