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The concept of parity type is proposed as a criterion of relationship among members of the Sceloporus aeneus – scalaris complex, with members of S. aeneus being regarded as viviparous and those of S. scalaris, as oviparous. The viviparous S. goldmani is regarded as a relative of S. aeneus, and S. a. subniger is not regarded as intermediate between S. scalaris and S. aeneus. The proposal by Davis and Smith that S. a. aeneus is oviparous and specifically distinct (as S. aeneus ) from S. a. bicanthalis (as S. bicanthalis ) is rejected. S. aeneus is hypothesized to have a biennial reproductive cycle. S. scalaris slevini auctorum is segregated into two subspecies: S. s. samcolemani subsp. nov. in the Sierra Oriental (northern end), and S. s. slevini sensu stricto in the Sierra Occidental (also northern end) of Mexico and of the adjacent United States.  相似文献   

3.
A revised list of the mosses of the Intermountain West, including all of Utah and Nevada and parts of surrounding states, is presented. Recorded are 342 species in 122 genera and 39 families in this region. Nomenclatural and taxonomic changes as well as floristic additions since the publication of Seville Flowers's book are included.  相似文献   

4.
A conservation gap analysis was conducted for the Intermountain Semi-Desert ecoregion to assess the representation of land-cover types within areas managed primarily for biodiversity objectives. Mapped distributions of plant communities were summarized by land-management status categories. The total amount of land permanently protected in the ecoregion is < 4%, and most types that are characteristic of the region have < 10%. Of 48 land-cover types, 20 were found to be particularly vulnerable to potential loss or degradation because of low level of representation in biodiversity management areas and the impact of expected land-use activities. Gap analysis data and findings will be useful in providing a regional perspective in project impact assessment and future conservation planning within this ecoregion.  相似文献   

5.
The Ferruginous Hawk, a breeding bird endemic to North America, was named Falco ferrugineus in 1838 by H. Lichtenstein, curator of the Berlin Zoological Museum. The type was collected by F. Deppe near present day Monterey, California. In 1844 G.R. Gray of the British Museum assigned the Buteo regalis to a Ferruginous Hawk specimen of unknown origin, but perhaps donated to the museum by John Phillips, a renowned British geologist. The species was known as Falco (Buteo) ferrugineus until the 1920s when it was discovered that this epithet was occupied. The next name in priority was Gray's Buteo regalis , which then became valid. The species has been known by a number of common names. Even though any reference to the rusty brown markings on the otherwise white plumage is no longer part of the species specific name, the Ferruginous Hawk continues to be the most frequently used common name.  相似文献   

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《Journal of Natural History》2012,46(25-28):1553-1570
The present document reports on the large amount of data relating to digenean parasites recorded from or known to be present in various hosts in lagoons of the northern coast of the western Mediterranean, which has been compiled from the literature of more than a century. In these lagoons, at least 72 nominal species of digeneans have been recorded. This total corresponds to approximately 12% of the 584 “marine” digenean species reported for Europe. Data are provided on the life cycles of 56 digenean species. The life cycle has been totally elucidated for 44 species (25 from fish, 19 from birds), and partly for the other 12 species (seven from fish, five from birds). This means that the life cycle is known for 61.1% of the recorded fauna (44/72) and partly for 16.7%, but remains unknown for 22.2%, making it, in this respect, one of the best understood digenean marine faunas in the world. In addition, a checklist is provided dealing with the cercarial and metacercarial forms recorded from lagoons of the northern coast of the western Mediterranean, which have been described only on the basis of characters of these larval stages and which remain without demonstrated links to a corresponding sexual adult stage in a vertebrate.  相似文献   

8.
《Journal of Natural History》2012,46(23-24):3091-3102
The aim of this study was to create an inventory of the coral species which occur in the shallow waters around Rodrigues island. The stony corals of Rodrigues island have received limited study. Corals were recorded, photographed and collected from reef slopes and lagoons by scuba diving and snorkelling during October 2001. A collection of previously collected corals in Rodrigues was also studied. A total of 130 named species in 40 genera of hard corals (125 species in 37 genera of zooxanthellate Scleractinia) were found during the present survey, together with eight unidentified species; 47 species of coral were new records for Rodrigues, 37 of which were new reports for the southern Mascarene archipelago; 23 species represented extensions of their known ranges, including two species that were previously considered endemic to other areas. The number of species found is similar to that previously reported from Mauritius (134), and significantly more than reported in earlier studies of Rodriguan corals (up to 89 species). This also complements recent reports for Rodrigues (132 species) and Mauritius (163 species).  相似文献   

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A checklist of the vascular plants of the House Range, Juab and Millard counties, Utah, is presented. A flora of 373 species and infraspecific taxa in 231 genera and 60 families are reported. The geology, physiography, climate, and plant communities are briefly discussed. Several endemics occur in the study area and a new taxon has been described.  相似文献   

11.
Summary

Jonah crabs, Cancer borealis, were collected in October 1971, June 1973, and March and April 1974 during trawl surveys of the continental shelf of the mid-Atlantic Bight and the shelf and slope east of Beaufort, North Carolina. In 171 trawls made from the M/V Blesk, R/V Columbus Iselin, R/V Albatross IV and R/V Eastward, 1626 jonah crabs were captured. Crabs were contagiously distributed within a depth range of 20–400 m. Maximum abundance occurred within 150–400 m and 8–13·9°C.

Male crabs ranged from 12 to 175 mm in carapace width; females from 13 to 152 mm. Three modal size groups for males and females were recognized: 13–40 mm, 41–80 mm and 81–110 mm. There was a fourth group of male crabs over 110 mm width. Crabs 40 mm were most abundant at depths of 75–150 m; crabs 41–80 mm were not captured in depths < 150 m, but were the dominant group in strata > 150 m. Larger crabs (81–110 mm) occurred from 40 to 400 m and reached maximum numbers at 150–400 m. Male crabs ≥ 111 mm were found only in 150–400 m.

Male crabs predominated in June. Sex ratios (M:F) ranged from 1·1:1 to 17:1. In October the ratios ranged from 1:16 to 2·4:1. In March and April the ratios were 2·9:1 and 1·9:1, respectively. In most cases the ratios were significantly different from 1:1.

The species was actively moulting in June, but recent or incipient ecdysis was not observed in October. Only one recently moulted crab was noted in March.

Gonad development in June was related to size. Most crabs ? 80 mm width were undeveloped or only slightly developed. Mature gonads were seen only in crabs ≥ 100 mm width. Testes and vasa deferentia of most males ≥ 150 mm were well to very well developed. No ripe ovaries were seen and no ovigerous individuals were taken in June. One berried female was observed in March.

The incidence of fouling organisms on crabs reflected the moulting history of the crabs. Sixty per cent of crabs in anecdysis and 14% of those in postecdysis were fouled. The predominant organism was the lepadid barnacle, Poecilasma inaequilaterale Pilsbry, which was attached to the gills in the branchial chamber.  相似文献   

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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;} Previous work by Wells in the Laramie Basin suggested that a coniferous forest/woodland covered the basin floor in the recent past (until the latest Holocene). We have found no evidence for this woodland and suggest instead that these scattered woodlands along sandstone outcrops and their immediate margins are outliers of the montane forest of the Medicine Bow Mountains, existing in their apparently anomalous locations due to favorable microenvironments set up by the topography and substrate.  相似文献   

14.
The role of the cyanobacterium Microcoleus vaginatus in cold-desert soil crusts is investigated using scanning electron microscopy. Crusts from sandstone-, limestone-, and gypsum-derived soils are examined. When dry, polysaccharide sheath material from this cyanobacterium can be seen winding through and across all three types of soil surfaces, attaching to and binding soil particles together. When wet, sheaths and living filaments can be seen absorbing water, swelling and covering soil surfaces even more extensively. Addition of negatively charged material, found both as sheath material and attached clay particles, may affect cation exchange capacity of these soils as well. As a result of these observations, we propose that the presence of this cyanobacterium may significantly enhance soil stability, moisture retention, and fertility of cold-desert soils.  相似文献   

15.
Summary

The genus Samariscus of the right eye flounder has thirteen known species including the two described here. A key is given to all the species, and the Japanese forms are reviewed. Samariscus japonicus Kamohara and S. latus Matsubara and Takamuki live in somewhat deeper water, 100 to 200 metres. A certain isopod parasite is often found in the branchial cavity of the ocular side of S. japonicus. S. xenicus n. sp. from Kochi frequents a depth of about 20 metres in the littoral zone. Kamohara's S. huysmani is relegated to synonymy of this new species. Also a flatfish from Tonking Bay represents a new species described herein as S. asanoi.  相似文献   

16.
《Journal of Natural History》2012,46(27-28):1745-1758
This study characterizes the ecology, behaviour and morphology of populations of Abrocoma schistacea and A. uspallata in north-western Argentina. We carried out live-trapping, tagging and recapture during 2006–2008. Burrow structure and vegetation were described. Diet composition and the activity of chinchilla rats were defined. Both species inhabit rock crevices in the pre-Andean foothills of the Monte Desert. Some of their morphological specializations for saxicolous life, such as foot pads for better traction on rocky surfaces and reduced nails, are convergent with those of other saxicolous species. Both species appear to be diurnal, with activity peaking in the early morning. Dietary analyses suggest trophic specialization by both species. Density of A. schistacea was of 0.15 ± 0.06 individuals ha?1; with individuals living in groups of 3–4 animals. Given their low abundance, restricted distribution and high level of habitat and food specialization, we urge that populations of this species be protected through effective management.  相似文献   

17.
Summary

In a resource-limiting situation, larger individuals exhibited more specialized habitat selection. The preference of both small and large Norrisia for seasonally stable algae indicated the importance of epiphytic film quality. When transplanted to a suboptimal habitat, large Norrisia climbed upward consistently more often than small snails, thereby encountering food-rich substrates. Downward movement enabled small snails to avoid risks associated with surge, while diversifying their array of potential food sources. Upwardly biased large snail dispersal persisted in the laboratory except in the absence of light, suggesting a phototactic origin for this bias.  相似文献   

18.
We describe, for the first time, the nesting behaviour of an Eragenia spider wasp, Eragenia congrua, based on field observations in the Brazilian Amazon. This species was observed nesting in holes at the base of the trunk of a Jacaranda copaia tree and provisioning nests with both amputated and non-amputated species of undetermined Corinna sp. (Corinnidae) spiders. The spiders are carried forward and grasped at the base of the chelicerae. Nesting is gregarious with females nesting in the same small area on successive days.  相似文献   

19.
Summary

Spirocamallanus olseni, previously known only from Madagascar in lutjanids and a remora, also infects the lutjanid, Lutjanus fulviflamma, in the Gulf of Elat; it becomes the second member of the genus reported from the Red Sea. Procamallanus elatensis sp. nov. from two siganid fishes becomes the second known Red Sea species in that genus, but appears most related to two other species from signaids. It can be characterized by having a distinct ledge in the buccal capsule anterior to the basal ring and an excretory pore anterior to the nerve ring. In the male, a gubernaculum and three pre-cloacal plus five post-cloacal papillae are present and the spicules have blunt tips with a crook and a ratio of 1:2·4 to 3·3. In the female, the vulva occurs 33 to 45% of the body length from the anterior end.  相似文献   

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