五株克雷伯氏菌噬菌体的生物学特性及比较基因组学研究

【目的】耐药性克雷伯氏菌属(Klebsiella)的细菌作为人类感染的重要病原,是临床治疗重要的挑战。本研究对多株克雷伯氏菌裂解性噬菌体的生物学特性和基因组特征进行比较分析,为其应用提供更多科学数据。【方法】使用双层平板法从人类和动物新鲜粪便、污水中分离纯化裂解性克雷伯氏菌噬菌体;通过磷钨酸染色和透射电镜观察其形态;采用双层平板噬菌斑法确定其宿主范围,测定温度和pH稳定性、一步生长曲线和体外抑菌效果等生物学特性;基于全基因组测序对分离株进行比较基因组学分析;通过体内抑菌试验评估噬菌体对多重耐药变栖克雷伯氏菌(Klebsiella variicola) BS375-3感染的大蜡螟(Galleria mellonella)幼虫的保护作用。【结果】5株噬菌体分别属于Schitoviridae (pKP-BM327-1.2)、Autographiviridae (pKP-M186-2.1、pKP-M186-2.2和pKV-BS375-3.1)、Drexlerviridae (pKP-BS317-1.1)家族;噬菌体pKV-BS375-3.1可裂解受试菌中的8株,pKP-BM327-1.2可裂解受试菌中的3株,pKP-M186-2.1、pKP-M186-2.2和pKP-BS317-1.1则分别裂解受试菌中的1株;5株噬菌体感染10-20 min后即进入指数增长期,在-20-37 ℃、pH 6-10环境下均能够保持稳定活性;感染变栖克雷伯氏菌BS375-3后经噬菌体pKV-BS375-3.1处理[感染复数(multiplicity of infection, MOI)=100]的大蜡螟幼虫96 h内存活率达到80% (8/10);5株噬菌体基因组长度在42-77 kb之间,未携带抗生素抗性基因和毒力基因,基于内溶素(endolysin)的溯源分析显示该蛋白在克雷伯氏菌噬菌体中呈现多样性,属内呈保守性。【结论】5株克雷伯氏菌噬菌体均具有较好的体外抑菌活性,生物学特性稳定,endolysin在噬菌体属内呈现保守性。宿主谱宽、潜伏期短的噬菌体pKV-BS375-3.1在治疗Klebsiella pneumoniae和K. variicola临床感染方面具有潜在应用前景。     

PB1样铜绿假单胞菌噬菌体PHW2的生物学特性

【背景】铜绿假单胞菌(Pseudomonas aeruginosa)是一种引起医院感染、急性感染和慢性感染的常见条件致病菌。多重耐药铜绿假单胞菌仍然是引起严重医院感染的常见病菌,其临床治疗面临严峻挑战。噬菌体具有特异性杀菌的能力,在防治铜绿假单胞菌耐药菌方面具有应用前景。【目的】分离能裂解碳青霉烯类耐药的铜绿假单胞菌的噬菌体,分析其生物学特性和基因组特征,为噬菌体治疗储备资源。【方法】采集环境水样,用双层琼脂平板法分离噬菌体,对其形态、一步生长曲线、感染复数等生物学特性进行研究;使用IlluminaMiSeq平台测定噬菌体的全基因组序列,利用Newbler3.0、GeneMarkS、BLASTp、Mauve2.4.0等生物信息软件进行拼接、注释和比较基因组学分析。【结果】分离到一株噬菌体PHW2,该噬菌体属肌尾病毒科成员,可裂解7株碳青霉烯类耐药的铜绿假单胞菌;其最佳感染复数为0.1。一步生长曲线结果显示,其感染宿主菌PA001的潜伏期为100 min,裂解期为360 min,裂解量为25 PFU/cell;噬菌体PHW2在温度25-50℃和pH 6.0-8.0范围内稳定;紫外照射7 min后PHW2活性明显下降;5%氯仿处理100 min内,PHW2仍保持较高的活性。噬菌体PHW2的基因组长65 984 bp,GC含量为55.69%,编码92个ORFs,不含tRNA。基因组比对结果显示PHW2与PB1样噬菌体高度相似。体外生物被膜抑制试验和清除试验结果显示,噬菌体PHW2能显著抑制宿主菌PA001形成的生物被膜并破坏24 h内形成的生物被膜。【结论】分离鉴定了一株新的PB1样噬菌体PHW2,对碳青霉烯类耐药的铜绿假单胞菌裂解能力强。生物学特性、基因组特征、体外生物被膜抑制试验和清除试验结果表明该噬菌体具有治疗铜绿假单胞菌耐药菌的潜力。     

PH826噬菌体与抗生素联用有效抑制多重耐药铜绿假单胞菌生物被膜的形成

【目的】铜绿假单胞菌(Pseudomonas aeruginosa)是一种重要的革兰氏阴性病原体,可以加重囊性纤维化患者的肺部感染,最终会导致患者的死亡。然而由于多重耐药(multi-drug resistant,MDR)和泛耐药(pan-drug resistant, PDR)铜绿假单胞菌菌株的出现,使其防控变得更为严峻。【方法】从养殖场污水中分离能有效裂解多重耐药铜绿假单胞菌的噬菌体,研究其形态特征、生物学特性、宿主谱范围、基因组特征和体外抑菌能力等,并采用噬菌体和抗生素联用的方法进行生物被膜的抑制试验。【结果】透射电子显微镜的形态分析和基因组分析结合表明,该噬菌体属于Nankokuvirus病毒属。生物学特性试验表明,PH826具有广泛的温度稳定性(4-60℃)和pH稳定性(3.0-11.0)。宿主谱测试显示,PH826可以裂解13株铜绿假单胞菌(包括人源和动物源),体外抑菌试验显示,PH826在感染复数(multiplicity of infection, MOI)分别为10、1、0.1时对铜绿假单胞菌均有强烈的裂解作用。根据基因组分析,PH826噬菌体的基因组大小为87 95...     

林麝源铜绿假单胞菌噬菌体vB＿PaeM＿PAMD02的生物学特性与全基因组序列分析

【背景】圈养林麝一半以上的死亡是由铜绿假单胞菌引起的化脓性疾病导致。另外,由于细菌的抗性增加,噬菌体是继抗生素后的另一抗菌选择。【目的】以分离自病死林麝肺脏的铜绿假单胞菌为宿主菌分离一株噬菌体,对其进行生物学特性、全基因组序列分析与体内抑菌试验。【方法】通过双层平板法分离纯化一株裂解性噬菌体,测定其裂解谱、最佳感染复数、一步生长曲线、热稳定性、最适生长pH等生物学特性,通过电镜观察其具体形态,进行全基因组测序与序列分析,并进行小鼠体内抑菌试验。【结果】分离到一株裂解性铜绿假单胞菌噬菌体并命名为vB＿PaeM＿PAMD02,该噬菌体具有透明且边缘清晰无晕环的噬菌斑,其裂解谱较窄,最佳感染复数为0.1,裂解潜伏期为40 min,裂解暴发量较高,热稳定性较高,可耐受弱碱环境。其全基因组大小为66 264 bp,GC含量为55.59%,序列注释结果显示该噬菌体具有92个开放阅读框,不含毒力与耐药基因,属于肌尾噬菌体科。小鼠体内抑菌试验结果显示了PAMD02对其宿主菌良好的抑菌效果。【结论】本研究分离的噬菌体PAMD02有较高的裂解效率,对不利环境有较好的耐受性,不含毒力基因与耐药基因,具有应用...     

一株污水源多重耐药大肠杆菌的耐药性检测及全基因组测序分析

【背景】水体环境分布广、流动性强,是耐药菌和耐药基因传播的主要媒介。【目的】了解北方污水厂大肠杆菌携带的耐药基因及可移动遗传元件情况。【方法】从北方污水厂筛选出一株多重耐药大肠杆菌,通过药敏试验进行耐药性检验,采用96孔板法测定菌株的最小抑菌浓度,利用酶标仪探究亚抑菌浓度抗生素对菌株生长的影响,并对菌株进行全基因组测序,对其携带的耐药基因及可移动遗传元件进行预测。【结果】大肠杆菌WEC对四环素、环丙沙星、诺氟沙星和红霉素具有耐药性,亚抑菌浓度的四环素、环丙沙星和诺氟沙星能够延缓或抑制菌株的生长。WEC菌株的基因组中包含一条大小为4 782 114 bp的环状染色体和2个大小分别为60 306 bp (pWEC-1)和92 065 bp (pWEC-2)的环状质粒。菌株共携带129个耐药基因,其中128个位于染色体上,在染色体上预测到原噬菌体、基因岛及插入序列的存在,部分可移动遗传元件携带有耐药基因。质粒pWEC-1中无耐药基因,pWEC-2含有1个耐药基因,在质粒基因组中预测到原噬菌体和插入序列。【结论】污水源大肠杆菌WEC是一株多重耐药菌株,其基因组中携带耐药基因和多种可移动遗传元件...     

一株肺炎克雷伯菌噬菌体的生物学特性及全基因组分析

【背景】随着抗生素的广泛使用甚至滥用,细菌耐药性问题日益显著,利用噬菌体治疗耐药致病菌的方法重新开始被人们关注。【目的】对一株烈性肺炎克雷伯菌噬菌体vB_KpnP_IME279进行生物学特性研究及生物信息学分析。【方法】以一株多重耐药的肺炎克雷伯菌为宿主菌,从医院污水中分离噬菌体,应用双层平板法检测噬菌体效价、最佳感染复数(Optimal MOI)、一步生长曲线以及裂解谱,纯化后通过透射电镜观察噬菌体形态;应用蛋白酶K/SDS法提取噬菌体全基因组,使用Illumina MiSeq测序平台进行噬菌体全基因组测序,测序后对噬菌体全基因组序列进行组装、注释、进化和比较基因组学分析。【结果】分离到一株新的肺炎克雷伯菌噬菌体,命名为vB_KpnP_IME279;其最佳感染复数为0.1,一步生长曲线显示潜伏期为20 min,平均裂解量140 PFU/cell,电镜观察显示该噬菌体属于短尾噬菌体科(Podoviridae)。基因组测序表明,噬菌体基因组全长为42 518 bp,(G+C)mol%含量为59.3%。BLASTn比对结果表明,该噬菌体与目前已知噬菌体的相似性较低,基因组仅70%区域与已知噬菌体有同源性。构建噬菌体主要衣壳蛋白的基因进化树,分析了噬菌体IME279与其他短尾科噬菌体的进化关系,结果表明该噬菌体是短尾科噬菌体的一名新成员。【结论】分离鉴定了一株新的肺炎克雷伯菌噬菌体,进行了生物学特性、全基因组测序和生物信息学分析,为研究肺炎克雷伯菌噬菌体与宿主之间的相互作用关系以及治疗多重耐药细菌感染奠定了基础。     

鸡源大肠杆菌噬菌体vB_EcoM-E33的分离鉴定和基因组特征及其治疗效果评价

【背景】大肠杆菌是导致规模化养殖家禽死亡的重要病原体,噬菌体防治耐药性细菌感染具有广阔的应用前景。【目的】从鸡场环境样本中分离出噬菌体,研究其生物学活性特征及其对白羽肉鸡大肠杆菌病的治疗效果。【方法】采用双层平板法分离纯化噬菌体vB_EcoM-E33(E33);利用透射电镜观察其形态特征;克隆噬菌体E33基因组序列并分析其基因组特征;通过裂解谱、最佳感染复数、理化因子耐受性和一步生长曲线确定噬菌体E33的生物学活性;构建白羽肉鸡大肠杆菌感染模型,检测噬菌体E33的治疗效果。【结果】从鸡场粪便样本中分离到一株Straboviridae科噬菌体E33,其宿主谱为35.4%(34/96),基因组全长为170625bp,包含271个开放阅读框和2个tRNA,无毒力基因和耐药基因。以Escherichia coli E32为宿主菌增殖,噬菌体E33的潜伏期为10min,暴发量为60PFU/cell;当感染复数为0.001时,噬菌体E33效价最高,达到1.93×10⁹PFU/mL;在50℃以下和pH3.0–11.0范围内活性稳定;对紫外线敏感。口服10⁸CFU/mL的致病性E.coliO78构建白羽肉鸡感染模型,肌肉注射10⁸PFU/mL噬菌体E33具有良好的治疗效果。【结论】噬菌体E33具有宿主谱宽、裂解性能高、理化因子耐受性强、不携带有害基因等优点,具有较好的开发价值,有望作为抗生素替代品用于鸡场致病性大肠杆菌病的防控。     

一株强裂解性大肠杆菌T1样噬菌体新成员的分离与鉴定

【目的】自然界中噬菌体种类繁多,其裂菌功能在针对细菌耐药方面具有潜在应用价值。不同噬菌体也呈现出显著的基因多样性及宿主特异性。从上海某猪场仔猪肠内容物样品中分离、纯化大肠杆菌的裂解性噬菌体,分析其生物学特性和病毒学特征,为探索应用噬菌体治疗细菌性感染提供研究材料。【方法】采用双层琼脂平板法分离、纯化噬菌体,观察噬菌斑特征,通过电镜观察噬菌体形态特征,测定其裂菌谱、最佳感染复数、一步生长曲线和生物学特性,进行噬菌体全基因组测序和遗传进化分析。【结果】分离、纯化获得一株能高效裂解大肠杆菌K-12菌株的噬菌体,命名为v B_Eco S_SH2(SH2),噬菌斑呈圆形、大而透明、边缘整齐。电镜观察SH2的头部呈二十面体立体对称,尾部较长。噬菌体的潜伏期为10 min,暴发期为60 min,裂解量高达121 PFU/感染细胞,其最佳感染复数为0.1。基因组测序和比对结果表明,SH2的核酸类型为ds DNA,基因组全长为49 088 bp,G+C%含量为45%,Gen Bank登录号为KY985004,结合电镜观察及BLASTp分析,确定其属于有尾噬菌体目长尾噬菌体科成员。同源性及进化分析表明,该噬菌体为大肠杆菌T1样噬菌体的新成员。【结论】分离鉴定了一株裂解效率极高的大肠杆菌T1样噬菌体,并确认其为T1样噬菌体新成员,为研究大肠杆菌噬菌体及其抗菌应用提供了新的实验材料。     

一株新的多重耐药福氏志贺菌噬菌体生物学特性及基因组分析北大核心CSCD

抗生素的大量使用和滥用造成细菌耐药性问题愈发严峻,噬菌体疗法作为一种精准治疗多重耐药病原菌的有效方法开始被人们日益重视。采用双层琼脂平板法从活性污泥中分离出多重耐药福氏志贺菌(Shigella flexneri)噬菌体P003,鉴定为肌尾噬菌体科(Myoviridae)。通过生物学特性测定表明P003的最佳感染复数为10,潜伏期约10 min;在4-70℃、pH 3.0-10.0的条件下保持活性。全基因组测序表明,噬菌体基因组长约68 721 bp,GC含量46.14%,预测编码99个开放阅读框(open reading frame,ORF),未发现已知耐药基因和毒力基因。全基因组多序列线性与进化树分析结果表明,P003与大肠杆菌噬菌体有较近的亲缘关系,但不能侵染大肠杆菌。从活性污泥原位分离到一株新的多重耐药福氏志贺菌噬菌体P003,为利用噬菌体疗法防治多重耐药病原菌S.flexneri感染提供了新的菌种资源。     

一株裂解性奶牛乳房炎源大肠杆菌噬菌体的分离鉴定及生物学特性分析

【目的】从新疆石河子地区奶牛粪样中分离裂解性大肠杆菌噬菌体(Escherichia coli phage),对其进行纯化及生物学特性分析。【方法】利用双层平板法从奶牛粪样中分离、纯化噬菌体,将纯化后的噬菌体浓缩液用醋酸双氧铀负染后通过透射电子显微镜观察其形态特征。对该噬菌体进行全基因组测序和遗传进化分析,同时测定噬菌体的宿主谱、最佳感染复数、一步生长曲线、热稳定性及酸碱稳定性。【结果】分离并纯化出一株裂解性噬菌体vB_EcoM_XJ2,噬菌斑圆形不透明,直径0.7 mm–1.2 mm;电镜显示其头部呈正多面体对称,有可伸缩性尾部;核酸类型为双链DNA,基因组大小为75.617 kb,G+C%含量为42.09%;其核酸序列与大肠杆菌噬菌体NJ01和vB_EcoP_SU10相似性高达94%。生物学特性研究显示该噬菌体能裂解多株临床分离的大肠杆菌;能耐受60°C左右高温,在pH 5.0–11.0范围内效价稳定;最佳感染复数为0.1,潜伏期为15 min,暴发期为95 min,裂解量约为10.6 PFU/cell。【结论】vB_EcoM_XJ2是一株在不同温度、不同酸碱性环境中有较强适应能力的裂解性肌尾科大肠杆菌噬菌体。     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Molecular phylogeny of Phebalium (Rutaceae: Boronieae) and related genera based on the nrDNA regions ITS 1+2

Parsimony analyses of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS 1 & ITS 2) for 38 taxa sampled from the Phebalium group (Rutaceae: Boronieae) and two outgroups confirm that, with the exception of Phebalium sensu stricto and Rhadinothamnus, six of the currently recognised genera within the group are monophyletic. The data indicate that Phebaliums. str. is paraphyletic with respect to Microcybe, and Rhadinothamnus is paraphyletic with respect to Chorilaena. Rhadinothamnus and Chorilaena together are the sister group to Nematolepis. Drummondita, included as an outgroup taxon, clustered within the ingroup as sister to Muiriantha and related to Asterolasia.The phylogeny suggests that the evolution of major clades within a number of these genera (e.g. Phebalium) relates to vicariance events between eastern and south-western Australia. Leionema is an eastern genus, with the most basal taxon being the morphologically distinct Leionema ellipticum from northern Queensland. Leionema also includes one species from New Zealand, but this species (as with some others) proved difficult to sequence and its phylogenetic position remains unknown. Taxonomic changes at the generic level are recommended.The authors wish to thank Paul G.Wilson, PERTH, for advice and discussion, and Paul Forster, BRI, for collecting and providing material of Leionema ellipticum. The project was supported by a Melbourne University Postgraduate Award (to BM), the Australian Biological Resources Study (ABRS), Australian Systematic Botany Society and Wolf Den (Australia) Investments.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

New species and new combinations in Peruvian Orchidaceae

seventeen new species and combinations are proposed in the generaChondrorhyncha, Cischweinfia, Cochlioda, Eloyella, Encyclia, Kefersteinia, Koellensteinia, Macroclinium, Rodriguezia, Solenidiopsis, andStenia. All new species are illustrated. A key is provided for 2-flowered species ofMacroclinium, PeruvianSigmatostalix, and PeruvianStenia. Solenidium (Solenidiopsis) peruvianum Schltr. is lectotypified.     

安徽牯牛降的丝孢菌Ⅰ

本文报导作者采自安徽枯牛降自然保护区的18种丝孢菌,分属于5个属,其中有3个新种:牛皮冻生尾孢(Cercospora paederiicola),山鸡椒假尾饱(Pseudocercospora litseae-cubebae),鸡血藤生假尾孢(P. millettiicola)和2个中国新纪录。文中对新种进行了描述及绘图,新记录种作了简要说明。研究的标本保存在中国科学院微生物研究所真菌标本室(HMAS)。     

Changes of dung beetle communities from rainforests towards agroforestry systems and annual cultures in Sulawesi (Indonesia)

Little is known about how tropical land-use systems contribute to the conservation of functionally important insect groups, including dung beetles. In a study at the margin of Lore Lindu National Park (a biodiversity hotspot in Central Sulawesi, Indonesia) dung-beetle communities were sampled in natural forest, young secondary forest, agroforestry systems (cacao plantations with shade trees) and annual cultures (maize fields), each with four replicates (n = 16 sites). At each site we used 10 pitfall traps, baited with cattle dung, along a 100 m transect for six 3-day periods. The number of trapped specimens and species richness at the natural forest sites was higher than in all land-use systems, which did not significantly differ. Each land-use system contained, on average, 75% of the species richness of the natural forest, thereby indicating their importance for conservation. However, a two-dimensional scaling plot based on NESS indices (m = 6) indicated distinct dung beetle communities for both forest types, while agroforestry systems and annual cultures exhibited a pronounced overlap. Mean body size of dung beetles was not significantly influenced by land-use intensity. Five of the six most abundant dung beetle species were recorded in all habitats, whereas the abundance of five other species was significantly related to habitat type. Mean local abundance and number of occupied sites were closely correlated, further indicating little habitat specialisation. The low dung beetle diversity (total of 18 recorded species) may be due to the absence of larger mammals in Sulawesi during historical times, even though Sulawesi is the largest island of Wallacea. In conclusion, the dung beetle fauna of the lower montane forest zone in Central Sulawesi appears to be relatively robust to man-made habitat changes and the majority of species did not exhibit strong habitat preferences.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.