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1.
A new genus of Metopiinae, Ojuelos Khalaim, gen. n., with a single species, Ojuelos juachicus Khalaim & Ruíz-Cancino, sp. n., is described from Jalisco Province in central Mexico. Ojuelos belongs to the group of three genera (Cubus Townes & Townes, Colpotrochia Holmgren and Triclistus Förster) having a high lamella separating the antennal sockets and reaching the median ocellus (this lamella possesses a dorsal groove in it, just below the median ocellus), but differs from these genera primarily by 1) face and clypeus not convex in lateral view, 2) face separated from clypeus by a shallow transverse impression, 3) mandible with lower tooth very strongly reduced, 4) flagellomeres of antenna strongly transverse, and 5) dorsal carinae of propodeum reduced. A portion of the key to the genera of Metopiinae is provided to distinguish the new genus.  相似文献   

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Lyubarsky GY  Perkovsky EE 《ZooKeys》2011,(130):255-261
Cryptophagus alexagrestis Lyubarsky & Perkovsky, sp. n. is described based on a fossil inclusion in Late Eocene Rovno amber (Ukraine). The new species is similar to the extant Cryptophagus skalitzkyi Reitter and Cryptophagus dilutus Reitter, differing from the latter by having a very transverse, short and dilated 10th antennal segment, and from the former by the very elongate segments of the flagellum.  相似文献   

4.
Yin ZW  Li LZ  Zhao MJ 《ZooKeys》2012,(175):75-86
Two new species, Pselaphodes linae Yin & Li, sp. n. (Hainan, Fujian) and Pselaphodes shii Yin & Li, sp. n. (Hainan) are described from South China. Taiwanophodes minor Hlaváč is reported from outside Taiwan for the first time. Illustrations of major diagnostic features are provided for all treated taxa. The latest key to Chinese Pselaphodes is modified to include the new species.  相似文献   

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The bee genus Chilicola Spinola (Xeromelissinae) is recorded from the State of Bahia, Brazil for the first time, based on a new species of the megalostigma group of the subgenus Hylaeosoma Ashmead. Chilicola (Hylaeosoma) kevani sp. n. is described and figured from males collected in Wesceslau Guimarães, Bahia. The species can be distinguished on the basis of coloration, size, integumental sculpturing, and structure of the hidden metasomal sterna and genitalia. A revised key to the species of the megalostigma group is provided.  相似文献   

7.
Brys R  Jacquemyn H 《Annals of botany》2011,107(6):917-925

Background and Aims

Reproductive assurance through autonomous selfing is thought to be one of the main advantages of self-fertilization in plants. Floral mechanisms that ensure autonomous seed set are therefore more likely to occur in species that grow in habitats where pollination is scarce and/or unpredictable.

Methods

Emasculation and pollen supplementation experiments were conducted under laboratory conditions to investigate the capacity for, and timing of autonomous selfing in three closely related Centaurium species (Centaurium erythraea, C. littorale and C. pulchellum). In addition, observations of flower visitors were combined with emasculation and pollen addition experiments in natural populations to investigate the degree of pollinator limitation and pollination failure and to assess the extent to which autonomous selfing conferred reproductive assurance.

Results

All three species were capable of autonomous selfing, although this capacity differed significantly between species (index of autonomous selfing 0·55 ± 0·06, 0·68 ± 0·09 and 0·92 ± 0·03 for C. erythraea, C. littorale and C. pulchellum, respectively). The efficiency and timing of autogamous selfing was primarily associated with differences in the degree of herkogamy and dichogamy. The number of floral visitors showed significant interspecific differences, with 1·6 ± 0·6, 5·4 ± 0·6 and 14·5 ± 2·1 floral visitors within a 2 × 2 m2 plot per 20-min observation period, for C. pulchellum, C. littorale and C. erythraea, respectively. Concomitantly, pollinator failure was highest in C. pulchellum and lowest in C. erythraea. Nonetheless, all three study species showed very low levels of pollen limitation (index of pollen limitation 0·14 ± 0·03, 0·11 ± 0·03 and 0·09 ± 0·02 for C. erythraea, C. littorale and C. pulchellum, respectively), indicating that autonomous selfing may guarantee reproductive assurance.

Conclusions

These findings show that limited availability of pollinators may select for floral traits and plant mating strategies that lead to a system of reproductive assurance via autonomous selfing.  相似文献   

8.
The Chinese species of the genus Ontsira Cameron, 1900 (Hymenoptera: Braconidae, Doryctinae) are reviewed. Eleven species are recognized, of which four new species are described from China and South Korea: O. abbreviata sp. n., O. henana sp. n., O. robusta sp. n., and O. rugivertex sp. n. Two species, O. ignea (Ratzeburg) and O. neantica Belokobylskij et Maetô, are recorded in China for the first time. A key to the Asian species of the genus Ontsira is provided.  相似文献   

9.
Nitrogen and water addition reduce leaf longevity of steppe species   总被引:1,自引:0,他引:1  
Ren H  Xu Z  Huang J  Clark C  Chen S  Han X 《Annals of botany》2011,107(1):145-155

Background and aims

Changes in supplies of resources will modify plant functional traits. However, few experimental studies have addressed the effects of nitrogen and water variations, either singly or in combination, on functional traits.

Methods

A 2-year field experiment was conducted to test the effects of nitrogen and water addition on leaf longevity and other functional traits of the two dominant (Agropyron cristatum and Stipa krylovii) and three most common species (Cleistogenes squarrosa, Melilotoides ruthenica and Potentilla tanacetifolia) in a temperate steppe in northern China.

Key Results

Additional nitrogen and water increased leaf nitrogen content and net photosynthetic rate, and changed other measured functional traits. Leaf longevity decreased significantly with both nitrogen addition (–6 days in 2007 and –5·4 days in 2008; both P < 0·001) and watering (–13 days in 2007 and –9·9 days in 2008; both P < 0·001), and significant differences in leaf longevity were also found among species. Nitrogen and water interacted to affect leaf longevity and other functional traits. Soil water content explained approx. 70 % of the shifts in leaf longevity. Biomass at both species and community level increased under water and nitrogen addition because of the increase in leaf biomass production per individual plant.

Conclusions

The results suggest that additional nitrogen and water supplies reduce plant leaf longevity. Soil water availability might play a fundamental role in determining leaf longevity and other leaf functional traits, and its effects can be modified by soil nitrogen availability in semi-arid areas. The different responses of species to resource alterations may cause different global change ramifications under future climate change scenarios.  相似文献   

10.

Background and Aims

The oriental forest ecosystem in Madagascar has been seriously impacted by fragmentation. The pattern of genetic diversity was analysed on a tree species, Dalbergia monticola, which plays an important economic role in Madagascar and is one of the many endangered tree species in the eastern forest.

Methods

Leaves from 546 individuals belonging to 18 small populations affected by different levels of fragmentation were genotyped using eight nuclear (nuc) and three chloroplast (cp) microsatellite markers.

Key Results

For nuclear microsatellites, allelic richness (R) and heterozygosity (He,nuc) differed between types of forest: R = 7·36 and R = 9·55, He,nuc = 0·64 and He,nuc = 0·80 in fragmented and non-fragmented forest, respectively, but the differences were not significant. Only the mean number of alleles (Na,nuc) and the fixation index FIS differed significantly: Na,nuc = 9·41 and Na,nuc = 13·18, FIS = 0·06 and FIS = 0·15 in fragmented and non-fragmented forests, respectively. For chloroplast microsatellites, estimated genetic diversity was higher in non-fragmented forest, but the difference was not significant. No recent bottleneck effect was detected for either population. Overall differentiation was low for nuclear microsatellites (FST,nuc = 0·08) and moderate for chloroplast microsatellites (FST,cp = 0·49). A clear relationship was observed between genetic and geographic distance (r = 0·42 P < 0·01 and r = 0·42 P = 0·03 for nuclear and chloroplast microsatellites, respectively), suggesting a pattern of isolation by distance. Analysis of population structure using the neighbor-joining method or Bayesian models separated southern populations from central and northern populations with nuclear microsatellites, and grouped the population according to regions with chloroplast microsatellites, but did not separate the fragmented populations.

Conclusions

Residual diversity and genetic structure of populations of D. monticola in Madagascar suggest a limited impact of fragmentation on molecular genetic parameters.  相似文献   

11.
A recent substantial rearrangement of the 882 described eleutherodactyline frog species has considerably improved the understanding of their systematics. Nevertheless, many taxonomic aspects of the South American eleutherodactyline species remain unknown and require further investigation using morphological, cytogenetic and molecular approaches. In this work, the karyotypes of the Brazilian species Ischnocnema juipoca (Atibaia and Campos do Jordão, SP), Barycholos cf. ternetzi (Uberlândia, MG, and Porto Nacional, TO), and Pristimantis crepitans (Chapada dos Guimarães and São Vicente, MT) were analyzed using Giemsa staining, Ag-NOR labeling, and C-banding techniques. All individuals had a diploid number of 22 chromosomes, but the Fundamental Numbers were different among species. The herein described low chromosome number of Pristimantis crepitans is unique within this genus, suggesting that cytogenetically this species is not closely related either to its congeneric species or to Ischnocnema. In addition, karyotype differences, mainly in the NOR position, clearly distinguished the two Barycholos populations, besides indicating the existence of a so far undescribed species in this genus. A taxonomic review could clarify the systematic position of P. crepitans and verify the hypothetic new Barycholos species.  相似文献   

12.
Pei S  Ma H  Shi B  Wu D  Zhou W 《ZooKeys》2011,(82):59-66
The present paper deals with a new species of the genus Lithobius Leach, 1814, Lithobius (Monotarsobius) songi sp. n.(Lithobiomorpha: Lithobiidae) recently discovered in Hebei Province, China. Morphologically it resembles Lithobius (Monotarsobius) holstii (Pocock, 1895) from China and Japan but could be well distinguished from latter by havinga Tömösváry’s organ slightly smaller than the adjoining ocelli, different leg plectrotaxy and tridentate claw of female gonopods. A key to the Chinese Lithobius (Monotarsobius)species is presented.  相似文献   

13.
Caballer M  Ortea J  Narciso S 《ZooKeys》2011,(115):1-18
Two new species of the genus Rissoella Gray, 1847 are described from Venezuela, one from the National Park Morrocoy, Rissoella morrocoyensis sp. n. and the other from the Wildlife Refuge Isla de Aves, Rissoella venezolanicola sp. n. Rissoella morrocoyensis sp. n. has a deep umbilicus (partly closed), preumbilical cord, black head, hypobranchial gland marked by a pale yellow boomerang-shaped ribbon and it lives on the leaves of the seagrass Thalassia testudinum Banks & König, 1805. Rissoella venezolanicola sp. n. has an angled preumbilical cord which extends to the columella delimiting a trapezoid, a hypobranchial gland marked by a yellow quaver-shaped ribbon and protoconch with fuchsia highlights. It lives on the brown alga Dictyota spp. The records of Rissoella in the Caribbean are revised and illustrations, a comparative table and a key to the Caribbean species known for the genus are provided.  相似文献   

14.
Hendrik Freitag 《ZooKeys》2013,(321):35-64
Ancyronyx buhid sp. n. and Ancyronyx tamaraw sp. n. are described based on adults and larvae, matched using their cox1 or cob DNA sequence data. Additional records of Ancyronyx schillhammeri Jäch, 1994 and Ancyronyx minerva Freitag & Jäch, 2007 from Mindoro are listed. The previously unknown larva of Ancyronyx schillhammeri is also described here, aided by cox1 data. The new species and larval stages are described in detail and illustrated by SEM and stacked microscopic images. Keys to the adult and larval Ancyronyx species of Mindoro and an updated checklist of Philippine Ancyronyx species are provided. The usefulness as bioindicators, the phylogenetic relationships and biogeographic aspects affecting the distribution patterns are briefly discussed.  相似文献   

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16.
The Chinese species of the genus Omalus Panzer, 1801 are revised and keyed for the first time. Eight species are recorded, of which four are new to science and one is new to China: Omalus aeneus (Fabricius, 1787), Omalus berezovskii (Semenov-Tian-Shanskij, 1932), Omalus potanini (Semenov-Tian-Shanskij, 1932), Omalus imbecillus (Mocsáry, 1889) (new to China), Omalus helanshanus sp. n., Omalus probiaccinctus sp. n., Omalus pseudoimbecillus sp. n., and Omalus tibetanus sp. n.  相似文献   

17.
We describe a new species of the bufonid toad genus Rhinella from transition montane forest of the buffer zones of the Yanachaga-Chemillén National Park and the Pui Pui Protected Forest (eastern slopes of Andes, Selva Central, Peru). The new species belongs to the Rhinella margaritifera species group (confirmed by mtDNA data) and differs from all its members by the absence of tympanic membrane and tympanic annulus. It is characterized by medium size (SVL 57.5–65.5 mm, n = 5), moderately developed cranial crests, absence of neural crest of vertebrae, absence of bone protrusion at angle of jaw, presence of lateral rows of enlarged tubercles, and absence of subgular vocal sac and vocal slits in males. In addition, based on the molecular phylogenetic analyses of selected Rhinella species we propose the monophylum containing R. chavin, R. festae, R. macrorhina, R. manu, R. nesiotes, R. rostrata, and R. yanachaga as a new species group under the name Rhinella festae species group.  相似文献   

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A new species, Notopygus longiventris Sun & Sheng, sp. n., collected from Benxi County, Liaoning Province, China, and N. emarginatus Holmgren, 1857, reared from Neurotoma sibirica Gussakovskij (Hymenoptera, Pamphiliidae) from Haicheng, Liaoning Province, are reported. The new species is placed within existing key to species.  相似文献   

20.
Three new species of Atopsyche Banks (Hydrobiosidae) from Brazil are described and illustrated: Atopscyhe (Atopsaura) blahniki sp. n., Atopsyche (Atopsyche) parauna sp. n., and Atopsyche (Atopsaura) galharada sp. n. Additional illustrations of the male genitalia of Atopsyche urumarca Schmid are provided, including its populational variation. Also, we provide new state records for 2 species: Atopsyche (Atopsyche) urumarca from São Paulo, and Atopsyche (Atopsaura) plancki Marlier from Santa Catarina.  相似文献   

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