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271.
Leucism in the western bluebird ( Sialia mexicana ) is reported from La Plata County, Colorado. 相似文献
272.
Stephen L. Wood 《西北部美国博物学家》2011,35(1)
New replacement names for junior homonyms are presented as follows; Acanthotomicus tuberculifer for A. (Mimips) tuberculatus Schedl 1967, Chactoptelius versicolor for C. (Acrantus) tricolor Schedl 1958, Hylesinopsis angolanus for H. (Aridiamerus) angolensis Schedl 1982, Hylurgops tuberculifer for H. tuberculatus Schedl 1947, Pseudothysanoes spinatifer for P. spinatus Wood 1956, Scolytodes aterrimus for S. ater (Hylocurosoma atrum Eggers) 1941, Scolytodes boliviensis for S. (Prionosceles) bolivianus Eggers 1928, Scolytodes brasiliensis for S. (Hexacolus) brasiliensis Schedl 1935, Scolytodes discriminatus for S. discedens Eggers 1943, Scolytodes elongatissimus for S. elongatus (Hylocurosoma elongatum Eggers) 1943, Scolytodes gennaens for S. genialis Wood 1978, Scolytodes laevigatulus for S. (Hexacolus) laevigatus Schedl 1962, Scolytodes laevicorpus for S. laevis (Hylocurosoma laeve Eggers) 1943, Scolytodes majus for S. major Eggers 1943, Scolytodes medialis for S. medius Eggers 1943. New synonymy is reported for Dactylipalpus niger Schedl (= D. unctus Wood), Dendroctonus armandi Tsai & Li (= D. prosorovi Kurenzov & Kononov), Sinophloeus porter Brèthes (= S. destructor Eggers). Species new to science include: Acacicis bicornis (New Guinea), Acacicis zeylanicus (Sri Lanka), Sphaerotrypes bengalensis (India), Sphaerotrypes costatus (North Andaman Island), Sphaerotrypes cristatus (Sri Lanka), Sphaerotrypes pentacme (Burma), Sphaerotrypes ranasinghei (Sri Lanka), Xylechinus ougeiniac (India), Xylechinus padus (India). 相似文献
273.
Studies in several areas in Arizona and New Mexico show that dwarf mistletoe ( Arceuthobium douglasii ) is rare in young Douglas-firs growing under infected overstories. Less than 5% of the Douglas-firs under 26 years old and less than 6% of those under 1.4m tall were infected in 77 mistletoe-infested stands. Both percent infection and mean dwarf mistletoe rating of young Douglas-firs increased as tree age, height, and stand dwarf mistletoe ratings increased. 相似文献
274.
A new species, Astragalus anserinus Atwood, Goodrich, & Welsh, is described from specimens taken from tuffaceous outcrops in the Goose Creek drainage of Box Elder County, Utah and Elko County Nevada. 相似文献
275.
The diet of Long - billed Curlew chicks is described for the first time. Five insect orders and one arachnid order were identified from nine stomach contents samples. Grasshoppers and carabid beetles were dominant prey items. 相似文献
276.
Julio L. Betancourt 《西北部美国博物学家》2011,44(1)
Plant macrofossils from packrat middens in two southeastern Utah caves outline development of modern plant zonation from the late Wisconsin. Allen Canyon Cave (2195 m) and Fishmouth Cave (1585 m) are located along a continuous gradient of outcropping Navajo Sandstone that extends from the Abajo Mountains south to the San Juan River. By holding the site constant, changes in the floral composition for a plot of less than one hectare can be observed, even if sporadically, over tens of millennia. At Allen Canyon Cave, Engelmann spruce-alpine fir forest was replaced by the present vegetation consisting of pinyon-juniper woodland on exposed ridgetops and cliffside stands of Douglas fir, ponderosa pine, and aspen. Xerophytic woodland plants such as pinyon, plains prickly pear, and narrowleaf yucca arrived sometime in the middle Holocene between 7200 and 3400 B.P. At Fishmouth Cave, Utah juniper in Holocene middens replaced blue spruce, limber pine, Douglas fir, and dwarf and Rocky Mountain junipers in late Wisconsin samples. Disharmonious associations for the late Wisconsin occur only at the lower site with the xerophytes Mormon tea, plains prickly pear, and narrowleaf yucca growing alongside subalpine conifers. One possible explanation involves the late Wisconsin absence of ponderosa and pinyon pines from the Colorado Plateaus. Released from competition at their lower limits, subalpine conifers were able to expand into lower elevations and mix with xerophytic plants found today in understories of pinyon-juniper and ponderosa pine woodlands. Quantitative climatic estimates are derived for the late Wisconsin by applying vertical gradients for temperature and precipitation to the amount of vegetation depression. The Fishmouth Cave sequence indicates a minimum lowering of 850 m for blue spruce, limber pine, and dwarf juniper. A depression of at least 700 m for Engelmann spruce and alpine fir is suggested for the Allen Canyon locality. Use of conservatively low gradients for stations below 2080 m yields a 3–4 C cooling from present mean annual temperature and 35 to 60 percent more rainfall than today. Steeper gradients associated with more mountainous terrain suggest a 5 C lowering in temperature and up to 120 percent increase over modern precipitation. 相似文献
277.
Data were gathered concerning the seasonal activity pattern of a population of Columbian ground squirrels ( Spermophilus columbianus ) in the Idaho Primitive Area. Adult females were significantly more active in June of all years than were adult males. A relationship between ground squirrel activity and temperature is postulated in which the squirrels alter their activity so as to avoid high temperatures and possible heat stress. 相似文献
278.
The height of oak ( Quercus gambelii Nutt.) stems was measured on several fire scars within the Uinta National Forest and vicinity and compared with the height of oak stems on adjacent, nonburned areas. A significant relationship exists between the recovery rate of oak after fire and elevation, with the recovery rate being greatest at low elevations. A trend also exists showing that recovery tends to be greater on south to westerly exposures than on north to easterly exposures. 相似文献
279.
A pallid bat ( Antrozous pallidus ) was taken 20 km SE Warren, Carbon County, Montana. This represents a 410 km range extension and a new record for Montana. 相似文献
280.
Diatoms epiphytic on Phragmites australis (Cav.) Trin. ex Steaded stems were collected from a single clone at the southern end of Provo Bay, Utah Lake, Utah. Diatom populations from both living and dead stem sections were analyzed. Species diversity in each sample was high, indicating that the stems provide a relatively stable habitat for diatom epiphytes. Of the 23 genera found, only Gomphonema and Navicula showed significant trends toward stem preference. The diatoms in this study support the current view that Utah Lake is a slightly saline, eutrophic system. 相似文献