甘肃潮水盆地潮参1井侏罗纪介形类化石

潮水盆地潮参1井发现Darwinula-Timiriasevia化石组合,化石丰富．保存完好。组合特征显示其地质时代为中侏罗世晚期。     

Chromosomal description of the rodent generaOecomys andNectomys from Brazil

We analysed karyotypes of five taxa of the rodent generaOecomys andNectomys, trapped in 14 localities in an area ranging from 8° to 29°S on Brazilian territory.Oecomys cf.concolor, collected in the Amazon and in two localities of the Cerrado biome, showed a 2n=60 karyotype constituted by a pair of large subtelocentric chromosomes, a small metacentric pair and 27 acrocentric pairs. The X chromosome was a large submetacentric and a subtelo-submetacentric, the morphology of the latter showing variable C-banding patterns. In all three localities the Y chromosome was a medium size heterochromatic acrocentric. Two individuals from the Cerrado had a heterochromatic acrocentric B-chromosome.Oecomys cf.bicolor presented two cytotypes, 2n=80 in the specimens from the Cerrado biome and 2n=82 in individuals trapped in the Amazon. The 2n=80 cytotype 1 showed a large subtelocentric, 22 biarmed pairs (medium to small) and 16 acrocentric autosomal pairs. The karyotype of the 2n=82 cytotype 2 is constituted by 15 biarmed chromosomes (median to small) and 25 acrocentric pairs with heterochromatic blocks at pericentromeric regions. The sexual pairs were the same (large submetacentric X and median acrocentric Y) in both cytotypes. InO. cf.concolor and in both cytotypes ofO. cf.bicolor the nucleolar organizer regions were observed in 1-3 pairs, located in the short arms.Nectomys genus presented two cytotypes, 2n=52–55 (N. rattus, with 0–3 biarmed heterochromatic accessory chromosomes) and 2n=56–59 (N. squamipes, bearing 0–3 biarmed, heterochromatic, B-chromosomes). These 2 cytotypes occupy disjunct regions of South America, with overlapping areas in the Brazilian states of Pernambuco, Bahia, and Mato Grosso do Sul.     

A new species of Caryospora (Apicomplexa: Eimeriidae) from the flathead snake, Tantilla gracilis (Ophidia: Colubridae), in southeastern Oklahoma

A single flathead snake, Tantilla gracilis , collected in early October 2010 from Choctaw County, Oklahoma, was found to harbor an undescribed species of Caryospora . Oocysts of Caryospora choctawensis n. sp. were spherical to subspherical, 15.8 × 15.0 (14-18 × 14-16) μm, with a thick, bilayered wall and a shape index (length∶width) of 1.1. A micropyle and an oocyst residuum were absent, but prominent Stieda and bubble-like sub-Stieda bodies were present as well as a bilobed polar granule near the oocyst wall. Sporocysts were ovoidal, 10.8 × 9.0 (10-12 × 8-9) μm, with a shape index of 1.2. The sporocyst residuum was spherical and composed of a cluster of granules often membrane-bound. This is the second time a caryosporan species has been reported from T. gracilis but the first coccidian ever described from a reptilian host in Oklahoma. Additional T. gracilis from Arkansas (n = 6), Oklahoma (n = 1), and Texas (n = 7) were examined, and a single specimen from Newton County, Arkansas harbored Caryospora gracilis Upton, McAllister, Trauth, and Bibb, 1992 , previously reported from T. gracilis collected in Arkansas and Texas.     

五种丛生状棕榈植物叶热值的月变化研究

对5种丛生状棕榈植物一欧洲棕、细叶棕竹、小箬棕、玲珑椰子、缨络椰子的叶片热值和灰分含量的月变化进行了研究,结果表明,5种植物具有较高的灰分含量,但灰分含量的月变化趋势各不相同;欧洲棕、细叶棕竹、小箬棕3种植物干重热值的月变化趋势有些差异,同属的缨络椰子、玲珑椰子干重热值的月变化趋势基本相似;缨络椰子、小箬棕的干重热值与灰分含量具有显著的线性相关(P<0．05),而其余3种植物的干重热值与灰分含量相关性不显著(P>0．05);从去灰分热值的月变化来看,细叶棕竹与小箬棕,缨络椰子与玲珑椰子的月变化趋势相似。     

Male and female meiosis in diploid and colchitetraploid Phlox drummondii Hook. (Polemoniaceae)

Comparative studies on male and female meiosis in diploid (2n = 2x = 14) and colchitetraploid (2N = 4x = 28) ornamental Phlox drummondii reveal higher chiasma frequency in embryo-sac mother cells as compared with pollen mother cells in the diploid, and significant differences in the pairing properties of chromosomes in the pollen mother cells and embryo-sac mother cells of the colchitetraploid. Male meiosis in the colchicine-induced autotetraploid was abnormal with 51.70% of chromosomes associated in quadrivalents and tridents in 96% of the cells. This was followed by discordant anaphase I disjunction. In the female meiocytes the chromosomes formed 14 bivalents in 86.66% of the cells. Quadrivalents (1–3) appeared only in 13.34% of the cells. It is concluded that meiosis in male and female cells of the colchitetraploid is governed and regulated by different controlling systems of gene(s).     

Cytological investigations of the interspecific hybrids of Nicotiana tabacum L. x N. glauca Grah

Interspecific amphihaploid and amphidiploid hybrids between Nicotiana glauca Grah. (2n = 24) and N. tabacum L. (2n = 48) cultivars BY 103 and K 326 were analysed. F1 amphihaploids (2n = 36) were viable and completely self- and cross-sterile, and mostly univalents were present during meiosis (with pairing range from 0 to 5). In some meiocytes, meiotic irregularities were observed, such as sporadic chromatin bridges and formation of restitution nuclei. The resultant F1 hybrids were easily converted to amphidiploids (2n = 72) via colchicine treatment of seedlings. The number of univalents and the frequency of PMCs containing unpaired chromosomes indicated that amphidiploids N. tabacum cv. BY 103 or K 326 x N. glauca represented quite a high pairing category. However, they were male sterile because pollen mother cells were arrested at the tetrad stage. The termination of development of PMCs, and consequently male sterility, are very rare in this kind of tobacco hybrids.     

云南无量山四种报春花属植物的核型研究

研究了云南无量山报春花属(Primula)3组4种植物的核型。体细胞中期染色体的数目和核型分别为：波缘报春P.sinuata Franch,2n=2x=22-20m(2SAT)_ 2st,着丝点端化值(T．C．％)为57．51％;无葶脆蒴报春P.sinoexscapa C.M.Hu,2n=2x=22=20m 2sm,T.C.％值为57．78％;滇北球花报春P．denticulata ssp.sinodenticulata (Balf.F.et Forrest)W.W.Smith,2n=2x=22=20m(4SAT) 2st,T.C.%值为56.79%;光叶景东报春P.interjacens var.epilosa C.M.Hu,2n=2x=18=2m(2SAT) 6sm(4SAT) 10st,T.C.%值为67.47%。简要讨论了报春花属植物可能的染色体原始基数和3个组的染色体基数。     

八个四倍体鹅观草属物种的核型研究

对8个鹅观草属物种的核型进行了研究。核型公式如下:纤穗鹅观草2n=4x=28=20m+8sm(2sat);紫穗鹅观草2n=4x=28=22m(2sat)+6sm;假花鳞草2n=4x=28=24m(2sat)+4sm;肃草2n=4x=28=22m+6sm(2sat);小颖鹅观草2n=4x=28=22m+6sm(2sat);纤瘦鹅观草2n=4x=28=24m(4sat)+4sm;变颖鹅观草2n=4x=28=20m+8sm(2sat);毛花鹅观草2n=4x=28=24m(2sat)+4sm。它们的核型属1A或2A型。其中后5个物种的核型为首次报道。     

海南岛晚泥盆世—早石炭世牙形刺

作者描述了海南岛昌江县石碌地区昌江组首次发现的牙形刺Palmatolepis gracilis gracilis Bransonet Me-hl,P.gracilis sigmoidalis Ziegler,Polygnathus ansatus Ziegleret Klapper,Polynodosus germanus(UlrichetBassler),Neopolygnathus dentatus(Druce)等和白沙县金波地区南好组第二段的Siphonodella levis(Ni),Polygnathus cf. inornatus Branson等,共8属20种,并据此将含化石地层分别确定为晚泥盆世法门期和早石炭世杜内期早期。指出以往认为是中泥盆统吉维特阶带化石Polygnathus ansatus Ziegleret Klapper与法门期牙形刺化石共同出现于昌江组并非构造混杂所致,但并不排除可能是化石再沉积作用的原因。同意将Polynodosus属从Polygnathus属中分离出来,在我国首次采用Polynodosus。     

Molecular evidence that diploid Stylosanthes humilis and diploid Stylosanthes hamata are progenitors of allotetraploid Stylosanthes hamata cv. Verano.

Restriction fragment length polymorphism analysis, using peroxidase, O-methyltransferase, phenylalanine ammonia-lyase, and coniferyl alcohol dehydrogenase cDNAs isolated from Stylosanthes humilis, as probes, provided molecular evidence for the genetic origin of the naturally occuring allotetraploid genotype Stylosanthes hamata cv. Verano (2n = 4x = 40). Hybridization patterns strongly suggest that the likely progenitors of S. hamata cv. Verano were a diploid S. humilis (2n = 2x = 20) and a diploid S. hamata (2n = 2x = 20) species.     

Trends in site-number change of rDNA loci during polyploid evolution in Sanguisorba (Rosaceae)

To elucidate the evolutionary dynamics of rDNA site number in polyploid plants, we determined 5S and 18S-5.8S-26S rDNA sites for ten species of Sanguisorba (2n=14, 28, 56) and a single species of each of three outgroup genera, Agrimonia (2n=28), Rosa (2n=14), and Rubus (2n=14) by the fluorescence in situ hybridization (FISH) method. We also estimated phylogenetic relationships among these species using matK chloroplast DNA (cpDNA) sequences, and reconstructed the evolutionary history of rDNA site number based on the maximum parsimony method. The 2n=14 and 2n=28 plants of all genera except Rosa carried two 5S rDNA sites, whereas Rosa and 2n=56 plants carried four sites. The 2n=14 plants had two 18S-5.8S-26S rDNA sites, whereas Sanguisorba annua and 2n=28 plants had four or six sites. Phylogenetic analysis showed that polyploidization from 2n=14 to 2n=28 has occurred once or three times in Sanguisorba and Agrimonia. The 5S rDNA sites duplicated during each ancestral polyploidization were evidently lost after each polyploidization. However, the duplicated 18S-5.8S-26S rDNA sites were all conserved after each polyploidization. Thus, the duplicated 5S rDNA sites tend to have been eliminated, whereas those of 18S-5.8S-26S rDNA tend to have been conserved in Sanguisorba. In the most parsimonious hypothesis, 2n=14 in S. annua is a secondary, putatively dysploid state, reduced from 2n=28.     

Meiotic configuration and chromosome number in some Iranian species of Ely mus L. and Agropyron Gaertner (Poaceae: Triticeae)

Chromosome numbers and analyses of meiotic metaphase I are reported for the following taxa: Agropyron cristatum subsp. incanum (2 n = 42), A. cristatum subsp. pecttnatum (2 n =28 – 33), Elymus elongatus subsp. ponticus (2 n = 69, 70), E. hispidus var. hispidus (2 n = 41 43), var. podperae (2 n = 42) and var. villosus (2 n = 41, 42), E. libanoticus (2 n = 14), E. pertenuis (2 n = 28, 28+1B), E. repens (2 n = 42), E. transhyrcanus (2 n = 40–42), E. hispidus var. villosus x E. cf. repens (2 n = 42). Chromosome numbers only are reported for the following taxa: E. gentri (2 n = 41, 42), E. nodosus subsp. dorudicus (2 n = 28), and E. elongatiformis (2 n = 56, 57). The haploid genomic constitution SP is reported for Elymus pertenuis. Variable chromosome numbers (2 n = 28–32) were observed in the meiotic metaphase I within single anthers of Agropyron cristatum subsp. pectinatum , and the supernumerary chromosomes in this taxon are assumed to have originated from crosses with hexaploids. Partial elimination of these supernumerary chromosomes probably occurs during archesporial mitotic divisions or at an early stage in the meiotic cycle. A hybrid, morphologically intermediate between E. hispidus and E. repens , was obtained from a seed of E. hispidus collected in the field. The meiotic metaphase I configuration in this E. hispidus hybrid suggests that the pollen parent may itself be a hybrid or hybrid derivative of E. repens x E. hispidus.     

天目山常绿阔叶林优势种群及其空间分布格局

常绿阔叶林是浙江省天目山国家级自然保护区重点保护植被类型,研究常绿阔叶林优势种群及其空间分布格局,可正确认识优势种群在常绿阔叶林中的地位和作用,为常绿阔叶林的保护和恢复重建提供理论依据。在天目山国家级自然保护区内,选择典型常绿阔叶林设置样地,样地大小100 m×100 m。用全站仪测定每株树木坐标。用优势度分析法确定群落优势种。采用Ripley'sK(d)函数分析优势种群空间分布格局和种间关联关系。结果表明,常绿阔叶林的优势树种数随大小级的增大而增加,但优势树种的聚集程度却降低。常绿灌木连蕊茶(Camellia fraterna)在幼苗、幼树中占绝对优势。在中树和大树中,以细叶青冈(Cyclobalanopsis gracilis)、青冈(Cyclobalanopsis glauca)和短尾柯(Lithocarpus brevicaudatus)为主,形成多优势种结构特征。连蕊茶、细叶青冈和青冈具有较稳定的显著聚集分布特征。豹皮樟(Litsea coreana var. sinensis)和短尾柯的分布格局波动较大。从整体上看,5个优势种群的分布格局都呈显著聚集分布特征。连蕊茶与细叶青冈、短尾柯、豹皮樟,以及细叶青冈与短尾柯、青冈与豹皮樟都有较强的物种空间依赖性。青冈和短尾柯相互独立生长,有显著负关联性。同科、属的细叶青冈和青冈也表现出显著负关联性。研究认为,种间关联关系具有传递性,可以从已知3个种的两对种间关联关系推出第三对种间关联关系。已知种间关联关系越显著,且尺度范围越宽,那么种间关联关系传递的稳定性也越高。结果认为,常绿阔叶树种是天目山国家级自然保护区常绿阔叶林群落的优势种,优势种均呈显著聚集分布,多数优势种间有较强的种间关联性。     

中亚热带森林群落不同演替阶段优势种凋落物分解试验

选择我国亚热带森林群落3个主要演替阶段的7个优势种（其中马尾松代表演替初期优势种,木荷和香樟代表演替中期优势种,甜槠、小叶青冈栎、青冈和乐昌含笑代表演替后期优势种）的凋落物,采用网袋法进行分解试验. 结果表明:马尾松凋落物分解得最慢,年分解速率为0.51;木荷和香樟居中,分别为0.55和0.61;小叶青冈栎和乐昌含笑分解得最快,分别为0.89和1.12.沿着植被顺向演替的梯度,凋落物分解速度呈现加快的趋势. 分解速率同凋落物的初始P、N和木质素含量及木质素/N比值呈极显著相关(P<0.01),同C/N比值有显著相关关系(P<0.05).凋落物的P、N和木质素含量及木质素/N比值是预测凋落物分解快慢的良好指标.     

Chromosomal and protein evolution in morphologically similar species of Praomys sensu lato (Rodentia, Muridae)

Evidence of extensive chromosomal evolution in a biologically and economically important group of African murids of the Praomys/Mastomys complex was provided by examination of G- and C-band chromosomal data on P. coucha (2n = 32), P. fumatus (2n = 38), P. hildebrandti (2n = 32), P. jacksoni (2n = 28), P. misonnei (2n = 36), and P. cf. tullbergi (2n = 35). A coding system was developed for the chromosomal characters, and analyses were performed by a computer program to find the shortest tree with a minimum of 35 autosomal rearrangements (pericentric inversions, complex translocations, centric fusions, centric fissions, tandem fusions, euchromatic additions, and heterochromatic additions). The resulting phylogenetic hypothesis differs from traditionally accepted hypotheses regarding this complex group of rodents. The cytogenetic data show that 1) there is no support for the dichotomy of Mastomys/Praomys previously based on morphology, 2) the 2n = 32 species from eastern Africa (P. hildebrandti) is distinct from the 2n = 32 species from southern Africa (P. natalensis), and 3) there is a close association between P. jacksoni and P. cf. tullbergi. Polyacrylamide gel electrophoresis of liver membrane proteins demonstrated few differences in protein mobilities between species and even fewer between individuals of the same species taken from different habitats and localities in Kenya. Monoclonal antibodies produced against liver proteins of one species and tested for reactivity to other species confirmed the evolutionary similarity of species of this complex. This immunologic approach may provide a robust data set for future phylogenetic studies of muroid rodents.(ABSTRACT TRUNCATED AT 250 WORDS)     

迷果芹（Sphallerocarpus gracilis）和红三叶（Trifolium pratense）的核型分析

对迷果芹（Sphallerocarpus gracilis(Bess.)K-Pol)和红三叶（Trifolium pratense L.)进行了染色体计数及核型分析。迷果芹的染色体数目为2n=20,核型公式为K（2n)＝2x=20=14m 4sm 2st(SAT);核型类型为2A,为较对称核型,该种植物的染色体数目及核型均为首次报道。红三叶的染色体数目有2n=14、16、28、32等类型,本研究首次报道了2n=14的核型公式为K（2n)=2x=14=2M 12m,核型类型为1B,为较原始的对称核型。     

Isolation and characterization of microsatellite markers from the marine isopods Serolis paradoxa and Septemserolis septemcarinata (Crustacea: Peracarida)

This study reports the successful isolation of highly informative microsatellite marker sets for two marine serolid isopod species. For Serolis paradoxa (Fabricius, 1775), 13, and for Septemserolis septemcarinata (Miers, 1875), eight polymorphic microsatellite markers were isolated using the reporter genome enrichment protocol. The number of alleles per locus (N(A) ) and the observed heterozygosity (H(O) ) encompass a wide range of variation within S. paradoxa (N(A) 3-31, H(O) 6-89%) and S. septemcarinata (N(A) 2-18, H(O) 9-94%). The suitability of the newly isolated markers for population genetic studies is evaluated.     

Past climate changes explain the phylogeography of Vitellaria paradoxa over Africa

The evolution of the savanna biome has been deeply marked by repeated contraction/expansion phases due to climate perturbations during the Quaternary period. In this study, we investigated the impact of the last glacial maximum (LGM) on the present genetic pattern of Vitellaria paradoxa (shea tree), a major African savanna tree. A range-wide sampling of the species enabled us to sample 374 individuals from 71 populations distributed throughout sub-Sahelian Africa. Trees were genotyped using 3 chloroplasts and 12 nuclear microsatellites, and were sequenced for 2 polymorphic chloroplast intergenic spacers. Analyses of genetic diversity and structure were based on frequency-based and Bayesian methods. Potential distributions of V. paradoxa at present, during the LGM and the last interglacial period, were examined using DIVA-GIS ecological niche modelling (ENM). Haplotypic and allelic richness varied significantly across the range according to chloroplast and nuclear microsatellites, which pointed to higher diversity in West Africa. A high but contrasted level of differentiation was revealed among populations with a clear phylogeographic signal, with both nuclear (F(ST) = 0.21; R(ST) = 0.28; R(ST) > R(ST) (permuted)) and chloroplast simple sequence repeats (SSRs) (G(ST) = 0.81; N(ST) = 0.90; N(ST) > N(ST) (permuted)). We identified a strong geographically related structure separating western and eastern populations, and a substructure in the eastern part of the area consistent with subspecies distinction. Using ENM, we deduced that perturbations during the LGM fragmented the potential eastern distribution of shea tree, but not its distribution in West Africa. Our main results suggest that climate variations are the major factor explaining the genetic pattern of V. paradoxa.     

Possible species specific courtship sounds by two sympatric cichlid fishes in Lake Malawi, Africa

Sounds were produced by the males of two species of cichlid fishes while courting females. Each courtship sound consisted of a series of distinct pulses occurring in rapid succession. Courtship sounds produced by Tramitichromis cf. intermedius and Copadichromis conophorus were significantly different in pulse rate and individual pulse durations. For C. conophorus calls (n=127) the mean ± sd number of pulses per call was 10 ± 3 and call duration was 181 ± 59 ms. There was a significant positive linear relationship between call duration and the number of pulses (r²=0.912, p < 0.001). The dominant frequency of the pulses in calls was 471 ± 50 (range 372–594) Hz (n=40 calls). T. cf. intermedius also produced a pulsed courtship call; data (mean ± sd) from two male T. cf. intermedius: 9 ± 2 pulses per call and duration 199 ± 44 ms (n=20 calls). The linear regression between call duration and number of pulses was positive (r²=0.463, p=0.001). Pulse rate within calls of T. cf. intermedius compared to C. conophorus were significantly different (p=0.018). Individual pulse durations were also significantly different (p=0.043) between species. However, interpulse intervals were not significantly different (p=0.177). These cichlids produced courtship sounds that were distinct by individual pulse durations and by pulse repition rate in a call.     

Revision of the genus Diplotaxis (Brassicaceae) in the Cape Verde Islands, W Africa

The genus Diplotaxis (Brassicaceae) in the Cape Verde Islands, W Africa, is revised. Nine taxa are accepted, of which five are described as new: D. antoniensis sp. nov., D. glauca, D. gorgadensis sp. nov., D. gorgadensis ssp. brochmannii ssp. nov., D. gracilis, D. hirta, D. sundingii sp. nov., D. varia sp. nov., and D. vogelii . All species are suffruticose, yellow-flowered perennials and belong to sect. Catocarpum . The species are endemic to the Cape Verde Islands, but show morphological and karyolog-ical affinity to the N African and Mediterranean D. harra s. lat. Analyses of morphological variation in 90 populations (400 plants) revealed a complex pattern, in particular in vegetative characters, most likely evolved by parallel ecogeographical differentiation in different islands. The chromosome number is 2n = 26 (n = 13) in the five taxa investigated. Self-pollination experiments indicate that the species are self-incompatible and outcrossing. Experimental F₁ hybrids with full seed set after open pollination were obtained in 30 interspecific combinations, and the taxa are considered fully interfertile. The taxa are thus isolated mainly by geographical and partly by ecological barriers and have evolved by vicariant evolution (most islands) and adaptive radiation (one island).