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1.
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;} Described as a new species is Penstemon flowersii Neese & Welsh from Utah. An illustration is provided. The species is named in honor of the late Seville Flowers, professor of botany at the University of Utah.    相似文献   

2.
Penstemon cyanathus Hook. ssp. subglaber Pennell, a plant found frequently in northwestern Utah, southeastern Idaho, and southeastern Wyoming, is elevated to species status. A new name, Penstemon holmgrenii Clark is proposed because P. subglaber is preoccupied.  相似文献   

3.
Named as a new species is Penstemon albifluvis J. L. England. The species is known from the Uinta Basin of Utah and Colorado.  相似文献   

4.
New taxa include Penstemon angustifolius Pursh var. dulcis Neese, P. leonardii Rydb. var. higginsii Neese, P. scariosus Pennel var. cyanomontanus Neese, and P. thompsoniae (Gray) Rydb. var. desperatus Neese. New nomenclatural combinations include: Penstemon acaulis L. O. Williams var. yampaensis (Penl.) Neese, P. duchesnensis (N. Holmgren) Neese, P. leonardii Rydb. var. patricus (N. Holmgren) Neese, and P. pachyphyllus Gray ex Rydb. var. mucronatus (N. Holmgren) Neese.  相似文献   

5.
A population of Penstemon pseudospectabilis M. E. Jones (Scrophulariaceae) on Cave Creek in Cochise County, Arizona, was used in an experimental test of reproductive fitness with three caging treatments: all flying pollinators excluded, hummingbirds excluded, and no exclusion. Twenty plants were chosen and three shoots on each used in the experiment. The flowers were 25.6 (s.d. = 1.5) mm long, the end diameter was 8.5 (s.d. = 1.0) mm, the tube opening was 6.5 (s.d. = 1.0) mm, and the greatest diameter, 75% distal from the receptacle, was 10.1 (s.d. = 0.8) mm (N= 59). Floral nectar contained 11.7% (s.d. = 2.9%) fructose, 13.8% (s.d. = 2.7%) glucose, and 74.5% (s.d. = 5.4%) sucrose (N = 74). There was some evidence, significant only for fructose, that nectar-sugar composition varies between morning and evening. Larger floral dimensions were correlated with lower sucrose and higher hexoses. Casual observation showed Xylocopa sp., small bees, flies, and hummingbirds to be visitors. There was no sign of nectar robbing. Five percent of flowers set seed with all pollen vectors excluded, 44% with hummingbirds excluded, and 63%with no exclusion. Seed set per fruit was 2 with all excluded, 23 with hummingbirds excluded, and 46 with no exclusion. Mean seed set on pollinated flowers was 60, with a range of 2 to 192. Multiple linear regression showed the fraction of fruit setting seed when hummingbirds were excluded to be related to larger flower diameters and shorter flowers. With no pollinator exclusion, fruits setting seed were related to larger diameters and nectar fructose. For seeds per fruit, multiple regression gave similar, but less clear, results. We conclude that P. pseudospectabilis is pollinated by both bees and hummingbirds, with other pollinators not to be excluded as possible contributors. We found no hard evidence of selective forces currently at work.  相似文献   

6.
Penstemon palmeri is a short-lived perennial herb colonizing disturbed sites in semiarid habitats in the western USA. In this study seed was harvested from six native and four seeded populations during two consecutive years. In laboratory germination trials at constant 15 C, considerable between-lot variation in primary dormancy and light requirement was observed. Four weeks of moist chilling (1 C) induced secondary dormancy at 15 C. Cold-induced secondary dormancy was reversed by one week of dark incubation at 30 C. This warm incubation treatment also reduced the light requirement of unchilled, after-ripened seed. Fluctuations in dormancy and light requirement of buried seeds have been linked to seasonal changes in soil temperature. Penstemon palmeri germination responses to temperature appear to be similar to those of facultative winter annuals.  相似文献   

7.
We studied the breeding system and flower visitors of White River penstemon, a rare endemic from the Uintah Basin of eastern Utah and western Colorado. Bagging treatments and hand-pollination treatments showed that Penstemon scariosus var. albifluvis has a mixed mating system: while some seeds and fruits are produced through selfpollination (both autogamy and geitonogamy), significantly more are produced when flowers are cross-pollinated. The primary flower visitors, and likely pollinators, were several species of native twig- and ground-nesting bees in the families Apidae, Halictidae, and Megachilidae. We found no differences in fruit or seed production between open-pollinated controls and hand-outcrossed flowers, suggesting that pollinator visits were sufficient to maximize female reproductive success. Management plans to conserve White River penstemon must recognize that full reproductive success of this rare plant taxon relies on a suite of pollinating bees, and that the species richness and abundances of bee visitors should be maintained.  相似文献   

8.
Recent taxonomic studies in Mimulus support the recognition of Mimulus evanescens , a new autogamous species morphologically allied with M. breviflorus and M. latidens . Initially known only from herbarium specimens, the most recent from 1958, M. evanescens was relocated in the field in 1990 in northern Lassen Co., CA. A second population was found in southern Lake Co., OR, in 1993. Mimulus evanescens is apparently confined to the Great Basin and its periphery, where it has been recorded from 10 localities across Idaho, Oregon, and California. Based on collection information and visits to the two extant populations, the new species appears to be restricted to vernally moist sites and fluctuating banks of intermittent streams or pools. Long-term utilization of such sites by livestock may have contributed to the present-day rarity of M. evanescens . The species should be added to federal and state lists of candidate endangered species pending the results of future field studies and surveys.  相似文献   

9.
The evolutionary divergence of five closely related populations of the yellow monkey flower. Mimulus guttatus was compared with the length of time the populations could have occupied the site and with the ability of the populations to intercross. Populations from the younger sites were found to be morphologically intermediate to populations from the older sites. Ability to intercross was not correlated with morphological divergence at this stage of evolution.    相似文献   

10.
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;} Seeds of 12 populations of Mimulus guttatus representative of the Wasatch Mountain ecotype were incubated for 17 months (one natural season plus a year) in five artificial climates found in phytotron studies to be important to the growth of the plants of that form of monkey flower. In all but the coldest climate, germination occurred promptly (3–8 days, on average), peaked during the first three weeks, and then tapered off gradually well into the second season. Generally, the amount and timing of germination was plastic, showing much the same range of responses in widely different climates both overall and for individual populations. However, in some cases, there were significant differences between populations indicative of polymorphism within the species. For example, germination was significantly slower, more variable, and less in amount the higher the elevation of origin of the populations. The responses of the population suggest the presence of both much plasticity and much polymorphism for germination characteristics in this form of M. guttatus.  相似文献   

11.
Disc gel electrophoretic assays of Mimulus plants showed young stems to contain at least 15 esterase bands. The 6 bands in the center of the gels were highly reproducible. Eighty-one populations representative of all the cytotaxonomic groups and of the Western Hemisphere geographic range of the Mimulus glabratus complex were assayed for those 6 bands. There was no apparent correlation between the distribution of the esterase bands and important environmental parameters such as elevation and latitude. Hence, their distribution did not appear to reflect environmental adaptive values. Each population was monophonic for its particular combination and intensity of esterase bands which is consistent with our previous suggestion that genetic drift is a strong component of the evolutionary pattern of the complex.  相似文献   

12.
The combination Artemisia tridentata Nutt. ssp. spiciformis (Osterhout) Goodrich & McArthur comb. nov. is made. This high elevation taxon was originally described at the species level and more recently has generally been treated as a form of A. tridentata ssp. vaseyana . The subspecies designation is supported by its parallel nature to the other A. tridentata  subspecies and by its relatively widespread and locally abundant populations. Also, a new variety of A. tridentata ssp. vaseyana is proposed.      相似文献   

13.
Survival, reproductive output, and transplant success were studied for an Iowa population of Penstemon tubiflorus (tube penstemon), a species that is rare to uncommon through much of its range. The population was discovered in 2003 and is one of only 6 populations that have been documented in Iowa. I began monitoring the new population when 2 cohorts were permanently marked, the first in 2005 and the second in 2007. I estimated survival, flowering, and reproductive output. Then, I introduced greenhouse-grown transplants to 2 new sites and the original site. Survival data showed that P. tubiflorus is a short-lived perennial (approximately 50% survival after 3 years) with substantial variation in the percentage of individuals that flower in a given year. Recruitment over the 5 years of monitoring varied from zero to 26 individuals per year. Transplant survival was site-specific. However, high survival and robust reproduction output of transplants at one site indicated that there are additional suitable sites near the parent population and suggested that these sites remain unoccupied due to limited seed dispersal. While it is unlikely that pollinator limitation is the cause of low reproduction, further study is needed on the pollination syndrome of the Iowa populations of this and other Penstemon species. Future studies should investigate the possibility that the species is limited by site-specific factors that inhibit germination and the survival of small seedlings. Estudiamos la supervivencia, el rendimiento reproductor y el éxito de transplante en una población de Penstemon tubiflorus (tube penstemon) en Iowa, una especie rara o poco común en gran parte de su rango. Esta población fue descubierta en 2003 y es una de sólo seis poblaciones documentadas en el estado. El monitoreo de la nueva población comenzó cuando se marcaron permanentemente dos cohortes, una en 2005 y la segunda en 2007. Se estimó la supervivencia en la floración y el rendimiento reproductor. Transplantes crecidos en invernadero se introdujeron en dos nuevos sitios y en el sitio original. Los datos de supervivencia indicaron que esta especie es una planta perenne efímera (con una supervivencia de aproximadamente 50% después de tres años), con variación considerable en el porcentaje de individuos que florecen en un año determinado. El reclutamiento de la población nativa durante los cinco años fue monitoreado y varió de cero a 26 individuos entre años. La supervivencia de los transplantes fue específica de cada sitio. No obstante, una alta supervivencia y vigorosa rendimiento reproductor de los transplantes en un sitio indicaron que existen sitios adecuados adicionales cerca de la población parental, y sugiere que estos sitios permanecen desocupados debido a la limitada dispersión de semillas. Aunque es improbable que la causa de la baja reproducción se deba a una escasez de polinizadores, se requiere más investigación sobre el síndrome de polinización de las poblaciones de Iowa de esta y otras especies de Penstemon. Se debe investigar la posibilidad de que la especie se vea limitada por factores específicos al sitio que inhiben la germinación y la supervivencia de las plántulas. Normal.dotm 0 0 1 231 1322 Iowa State University 11 2 1623 12.0 0 false 18 pt 18 pt 0 0 false false false /* 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-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:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";}  相似文献   

14.
A comparison of the floral visitors of two closely related plant species, Penstemon cyananthus and P. eatonii suggests that flower shape and color may affect the number and type of pollinators, and the ability of the plant to set fruit. Penstemon cyananthus, which is most attractive to hymenopteran visitors, has a blue flower, large in diameter, that is positioned as a convenient “landing pad.” Although many types of insects visit the flower, the transport of pollen directly to flowers of another individual of the same species is somewhat inefficient, since fruiting success is low (66.7 percent). The tubular red flowers of P. eatonii are narrow and droop downward from the stem. The nectar is accessible to a specific and well-adapted visitor, the hummingbird. This less promiscuous, bird-pollinated species sets fruit more successfully (82.4 percent) than P. cyananthus.  相似文献   

15.
Cymopterus higginsii and Penstemon atwoodii are named and described from materials collected in the Kaiparowits Plateau vicinity of eastern Kane County, Utah. Habitat, distribution, and probable affinities are outlined.  相似文献   

16.
Iridophora clarki gen. nov., sp. nov., Megaselia sembeli sp. nov. and M. kodongi sp. nov. are described. The females of I. clarki attack the workers of the ant Iridomyrmex cordatus (Smith). The same ant species is also attacked by M. sembeli, and the morphology of this species indicates that it is close to P. beirne Brues, the typespecies of the genus Plastophora. The loss of the type-material of the latter species prevented synonomy of the genus when it was re-evaluated (Disney, 1978). The detailed examination of M. sembeli now indicates that the genus Plastophora is a synonym of Megaselia (syn. nov.). A consequence is that P. dubitata Brues, 1935 becomes a homonym of M. dubitata (Malloch, 1912) and the replacement name M. bruesi nom. nov. is proposed. The females of M. kodongi attack workers of a species of Pheidologeton which forages on the forest floor. The habit of Iridomyrmex cordatus in using covered ways up trees appears to be related to its extreme vulnerability to attack by these two phorides.  相似文献   

17.
Invasive alien plants have long been recognized as a threat to low-elevation, disturbed environments, but the case of Linaria vulgaris Mill. in Yellowstone National Park and Gallatin National Forest shows that invasions can also spread to high-elevation natural reserves. Because invasions in protected areas are a product of complex processes occurring over a broad range of scales, we argue that a multi-scale research approach is needed to capture both patterns and potential mechanisms of the invasion process. Mapping L. vulgaris at the landscape scale, we found the species occupying a broad range of sites, apparently originating from just 2 historical sources, colonizing both human-caused and natural disturbances. Analyzed at the stand scale, patches tend to aggregate in newly invaded areas and disperse in heavily infested areas. The data suggest that patches grow in size by clonal growth and in number by creation of new satellite patches. Radial patch growth rates are related to site characteristics. Clonal patch scale analysis shows that ramet densities and Linaria 's effects on native plants are highest in patch centers. Both mean ramet height and reproductive vs. vegetative ramet height ratio are higher in patch cores. These results suggest that L. vulgaris may displace natural vegetation by maintaining vigor even in large and old clonal patches. Our results confirm that L. vulgaris is a significant threat to native biodiversity in open, human- or naturally disturbed environments in protected areas of the Rocky Mountains. A multi-scale method can allow managers to better understand patterns of invasion and prioritize management activities to control invasive alien plants, especially in heterogeneous protected area landscapes.  相似文献   

18.
A new species, Mentzelia (sect. Bartonia ) cronquistii , subfamily Mentzelioideae, is described and a new combination, M. (sect. Bartonia ) marginata (Osterhout) is made. These two species of the Colorado Plateau are closely related to each other, but their relationships to other species in section Bartonia are obscure.  相似文献   

19.
20.
A new species of pulvinate wild buckwheat, Eriogonum soredium (Polygonaceae, Eriogonoideae) is described from near-barren limestone slopes in the Grampian Hill area near Frisco, Beaver County, Utah. The new species is outwardly similar to E. shockleyi S. Wats, but may be readily distinguished by its glabrous (not pubescent) flowers and fruits, generally smaller leaves, more numerous involucres per head, turbinate (not campanulate) involucres with 5, rarely 4 (not 5 to 10) teeth, and the smaller flowers.  相似文献   

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