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1.
Three wild Penstemon hybrids are documented herein: Penstemon clevelandii × spectabilis, P. centranthifolius × spectabilis , and P. centranthifolius × eatonii . Each putative hybrid was compared to its respective parental species using manifold floral and vegetative characters for which the parents differed. For each hybrid hypothesis, characters were counted as being intermediate or not intermediate. There were significantly more intermediate characters in all 3 cases (one-sided sign tests, P Penstemon species evidently do hybridize naturally, and for nearly all characters the hybrids are consistent with the view that the parents differ largely by additive genetic effects.  相似文献   

2.
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   

3.
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   

4.
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   

5.
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   

6.
Described as new species are Erigeron cavernensis Welsh & Atwood from the Schell Creek Range and Currant Mountain, White Pine County, Nevada, and Penstemon idahoensis Atwood  相似文献   

7.
Field and herbarium studies of Penstemon cyananthus Hook. ssp. longiflorus Pennell suggest that this taxon be elevated to species rank.    相似文献   

8.
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   

9.
The status of 382 vascular plant taxa with distribution in Utah is presented. Some 66 species are possibly endangered, 198 threatened, 7 extinct, and 20 extirpated within the state; 4 species have questionable taxonomic status. Included in the list are nearly 225 species of endemic plants, many of which are among the possibly endangered, threatened, and extinct or extirpated plants. Bibliographic citations, type locality, status, and distribution by counties is included for each species or infraspecific taxon. Two new species are described: Psoralea pariensis and Eriogonum natum. One new name, Astragalus barnebyi, is proposed; and one new variety, Eriogonum umbellatum var. deserticum, is proposed. The following new combinations are made: Cycladenia humilis var. jonesii; Aralia racemosa ssp. bicrenata; Heterotheca jonesii; Hymenoxys depressa; Xanthocephalum sarothrae var. pomariense; Thelypodium integrifolium var. complanatum; Thelypodium sagittatum var. ovalifolium; Arenaria kingii var. plateauensis; Psorothamnus thompsonae; Najas caespitosus; Oenothera gouldii; Eriogonum corymbosum var. revealianum; Penstemon humilis var. obtusifolius; Penstemon lentus var. albiflorus; and Viola purpurea var. charlestonensis.    相似文献   

10.
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   

11.
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   

12.
All of the known records of Plecoptera occurring in southeastern Idaho have been compiled in this list, which includes a number of new records obtained by the authors. The study region includes all of the streams in the Snake River and Great Basin drainages of the state found east of the Wood River and south of the Continental Divide and covers about one-third of the state's 216,413 km 2 area. A total of 71 species were found to occur in the area. These are listed by family and the specific habitats in which each is known to occur are noted.  相似文献   

13.
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   

14.
《Journal of Natural History》2012,46(35-36):2305-2320
Recent studies indicate that populations historically called Leptodactylus fuscus (Schneider, 1799) comprise at least three well‐differentiated lineages. Herein, we describe the reproductive ecology of a southeastern clade population of L. fuscus, and review the characters of the reproductive ecology for several populations of the northern and southeastern clades. Most reproductive activity occurred in December and January, which coincided with the highest rainfall period. Males had an aggregated spatial distribution in the central area of the ponds. Three courtship interactions were observed. A female was observed closing the entrance to a burrow with moist sand after oviposition. This behaviour is described for the first time in L. fuscus. The review of the reproductive biology of the northern and southeastern clades indicates a relatively high plasticity in L. fuscus. Furthermore, the results corroborate the suggestion, based on molecular data, that the northern and southeastern clades of L. fuscus represent distinct evolutionary units.  相似文献   

15.
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   

16.
New species and varieties of the plant genus Eriogonum (Polygonaceae) that occur in Nevada are proposed. Eriogonum tiehmii and E. ochrocephalum var. alexanderae are endemic to Nevada, and E. lewisii is restricted to extreme northeastern Nevada and adjacent Utah. These entities belong to the subgenus Eucycla. Two varieties of E. umbellatum (of the subgenus Oligogonum) are proposed. The first, var. juniporinum , is found in eastern Nevada and in the desert ranges of southeastern California. The second is var. furcosum , which is restricted to the Sierra Nevada. One new combination is also proposed: E. nudum var. gramineum .      相似文献   

17.
The flea Anomiopsyllus amphibolus is reported from southeastern Oregon, a range extension of about 475 km from the nearest reported localities in northwestern Utah.  相似文献   

18.
An expression of Centaurium namophilum (Gentianaceae), long confused with C. exaltatum in the Great Basin of the western United States, is described and designated as var. nevadense. It may be separated from the Death Valley region endemic, var. namophilum, by its broader leaves, its diffuse corymbose cyme, the ultimate peduncles that are longer than the flowers, its medium to deep rose pink corolla, and its stamens that equal or exceed the style and are only slightly exserted from the corolla-tube. The var. nevadense occurs from eastern California to western Utah, and from southeastern Oregon and adjacent Idaho south to the northern Mojave Desert of southeastern California. Centaurium exaltatum may be distinguished from the new variety by its broader, more elliptical leaves, dichotomous peduncles, paler pink or bluish and generally four-merous flowers, shorter and more blunt corolla lobes, and a thicker, more included style and stigma.  相似文献   

19.
An isolated stand of ponderosa pine ( Pinus ponderosa ) is surviving on an extremely harsh site in southeastern Oregon. Seed production is low because of insects, primarily pine coneworm ( Dioryctria auranticella ), feeding in developing cones. Seedling establishment is infrequent and difficult because of drought and coarse, rocky soils. A rock-mulch soil surface probably reduces interspecific competition. Because stand size is small (  相似文献   

20.
An insect survey was conducted on the Idaho National Engineering Laboratory during the summers of 1981–1983. This site is on the Snake River Plains in southeastern Idaho. Presented here is an annotated checklist of the Coleoptera collected. Successful collecting methods, dates of adult occurrence, and relative abundance are given for each species. Relevant biological information is also presented for some species.  相似文献   

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