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431.
Occurrences of mountain lions ( Puma concolor ) in Nebraska have been steadily increasing; however, reproductive activity in mountain lions has not been documented in the state. We present the first evidence of mountain lion reproduction in Nebraska since mountain lions recolonized the state in the early 1990s. On 28 February 2007, a spotted kitten was hit by a vehicle in northwestern Nebraska; and based on body length and weight, we estimate its age at 3.9 months. On 20 December 2008, a female mountain lion and spotted kitten were photographed in the northwestern part of the state. On 9 May 2009, a female mountain lion with a juvenile was also photographed. All records were from the Pine Ridge region of Dawes County, Nebraska. Our records suggest that mountain lions are establishing a permanent population in at least one region of Nebraska. 相似文献
432.
The mountains of north central Washington contain a variety of habitat types, from shrubsteppe to high alpine meadows. While native bee surveys of some surrounding areas like the Columbia Basin are fairly complete, little work has been done in the mountains of north central Washington to document the diversity of bees found therein. We conducted a survey of native bees in the Tonasket Ranger District of the Okanogan-Wenatchee National Forest during summer 2004. Collections yielded a diverse bee fauna (140 species in 24 genera) visiting diverse floral elements (57 plant species in 18 families). These preliminary data suggest that a rich bee fauna exists in the Okanogan Basin and surrounding mountains. 相似文献
433.
We tested the hypothesis that allochthonous carbon is important in the diet of the endemic pupfish Cyprinodon diabolis over a 3-year period in Devils Hole, Nevada. Devils Hole is a cavernous limnocrene located in the Mojave Desert approximately 15 m below the land surface and receives direct solar radiation <7% of the total time during the year. The system is dominated by filamentous cyanobacteria in the summer and supports about 15 invertebrate species and the endemic pupfish C. diabolis . We examined food web structure and measured autochthonous carbon production and entry of allochthonous carbon with funnel traps. Stable isotopes were used to compare contributions of each carbon source. Allochthonous carbon contributed 2971 kj ⋅ yr -1 (60%) of the total available energy to the food web compared to only 2000 kj ⋅ yr -1 autochthonous production. A major stochastic rain event delivered more terrestrial carbon to Devils Hole in l hour than annual allochthonous carbon, estimated from data collected with funnel traps. Mixing models with δ 15 N, δ 13 C, and δ 34 S showed a seasonal shift in diet for C. diabolis from filamentous cyanobacteria in the summer to the collector/gathering insect Stenelmis calida in the winter. Stenelmis tissue had high proportions of allochthonous plant carbon in the winter. 相似文献
434.
435.
Wilson J. E. M. Costa 《Journal of Natural History》2017,51(27-28):1609-1624
Nothobranchius guentheri and Nothobranchius melanospilus, the two seasonal killifishes of the genus Nothobranchius occurring in Zanzibar Island, Tanzania, were involved in past taxonomical mistakes and are still misidentified in museum collections. A historical review is herein presented and both species are redescribed on the basis of type material and recent collections. Nothobranchius guentheri, a popular aquarium fish, is endemic to Zanzibar, and N. melanospilus, geographically widespread in East Africa, occurring both in Zanzibar and in continental river basins. These species are distinguished by a series of morphological features not previously reported in the literature, including pre-dorsal length and relative position of the anterior portion of the dorsal-fin skeletal support and vertebrae; number of gill-rakers of the first branchial arch, caudal-fin rays, scales of the longitudinal series, series of scales around caudal peduncle, and vertebrae; frontal squamation; and arrangement and number of neuromasts of the supraorbital series. The present taxonomic revision comprising N. guentheri and N. melanospilus, the oldest species names of the genus in the East African biodiversity hotspot, is important to improve the knowledge of the genus in a region where its taxonomy is still problematic 相似文献