Delineation of Chondrus (Gigartinales, Florideophyceae) in China and the origin of C. crispus inferred from molecular data

Complete nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) sequences were obtained for 18 Chondrus populations collected at 15 sites from eight countries worldwide. Pairwise comparisons with the multiple alignment revealed that intraspecific divergences of ITS sequences ranged from 0.3 to 1.8% in C. crispus Stackhouse (except for the entity SVLH from France) and from 0.0 to 0.6% in C. ocellatus Holmes, whereas interspecific divergences in Chondrus varied from 1.4 to 5.0%. Three phylogenetic methods (neighbour joining, maximum parsimony and maximum likelihood) confirmed three main lineages: the North Atlantic lineage containing entities of C. crispus from Canada, France, Germany, England, Portugal, Ireland and Wales; a second lineage comprising three species: C. sp. 1, C. armatus (Harvey) Yamada et Mikami, and C. pinnulatus (Harvey) Okamura from the Northern Pacific; and a third lineage containing just one species: C. ocellatus from the Northern Pacific. Chondrus yendoi Yamada et Mikami separated from other Chondrus species singly. nrDNA ITS data indicate that a previous assignment of C. sp. 2 to Mazzaella japonica (Mikami) Hommersand may be incorrect, and additional evidence is needed to resolve the generic placement of this entity. It is inferred from the nrDNA ITS data that three Chondrus species are presently known in China with two, C. ocellatus and C. nipponicus, in Qingdao and two, C. armatus and C. nipponicus, in Dalian. We hypothesize that the ancestor of North Atlantic C. crispus had a Pacific origin, and that the present distribution of C. crispus in the Atlantic Ocean correlates with a trans-Arctic dispersal and vicariance events associated with Pleistocene glaciation maxima.     

Phylogenetic relationships within Pyrenodesmia sensu lato and the role of pigments in its taxonomic interpretation

Most lichens of the family Teloschistaceae (Ascomycota) produce yellow-orange-red anthraquinone pigments. However, the genus Pyrenodesmia encompasses species in which anthraquinones are absent and replaced by a gray pigment Sedifolia-gray. It was shown recently that these species are related to taxa with both anthraquinones and Sedifolia-gray (Caloplaca xerica group, C. haematites group, and C. cretensis) and to species with a brown pigment instead of both anthraquinones and Sedifolia-gray (C. demissa, C. obscurella, and C. reptans). Nevertheless, relationships between mentioned anthraquinone-containing and anthraquinone-lacking species remained unclear. In total, 8 DNA loci from 41 species were used here to resolve these uncertainties. We concluded that C. demissa, C. obscurella, and C. reptans are rather distant from the core of Pyrenodesmia, and we place them outside of Pyrenodesmia sensu lato. Within Pyrenodesmia sensu lato, three lineages were revealed and recognized on a generic level: the genus Pyrenodesmia sensu stricto (21 species), the genus Kuettlingeria (14 species), which is resurrected here, and the genus Sanguineodiscus (4 species), which is newly described here. The genus Pyrenodesmia includes taxa that never contain anthraquinones, but Sedifolia-gray. It matches with the former C. variabilis group. Taxa of the genera Kuettlingeria and Sanguineodiscus have anthraquinones in their apothecia and Sedifolia-gray in their thalli. The genus Kuettlingeria includes the former C. xerica group plus C. cretensis and C. diphyodes. The genus Sanguineodiscus includes the former C. haematites group and C. bicolor. The identity of Kuettlingeria (Caloplaca) diphyodes was clarified and the name Pyrenodesmia helygeoides was resurrected. Twenty-four new combinations were proposed.     

长白山区苔草泥炭沼泽植物物种多样性

本研究以长白山区典型苔草沼泽为对象,分析了密丛型苔草(瘤囊苔草、乌拉草)沼泽和疏丛型苔草(毛苔草)沼泽的植物物种多样性.结果 表明:3种苔草沼泽植物群落共有83个物种,隶属于36科59属.其中,乌拉草沼泽有71个物种,瘤囊苔草沼泽有61个物种,毛苔草沼泽有26个物种.密丛型苔草沼泽植物物种数和物种丰富度明显高于疏丛型苔...     

虾池拟柱胞藻爆发的生态因子调查

2002～2003年,在广东珠三角地区凡纳滨对虾(Litopenaeus vannamei)低盐度养殖虾池水体生态的调查过程中发现部分虾池爆发拟柱胞藻(Cylindrospermopsis raciborskii).在调查的低盐度虾池中,共统计20个拟柱胞藻爆发的虾池,其种群密度平均高达7.74×10⁷ filaments·L^-1,平均优势度达47.0%.虾池水体平均水温为30.3℃,pH为8.9,盐度1.4,透明度19cm,化学耗氧量为24.3mg·L^-1.拟柱胞藻爆发的虾池水体环境表现为高水温、高pH、高有机质、低盐度且水体不断被搅动;通常爆发在对虾养殖的中后期富营养化水体.调查发现大量的拟柱胞藻对虾池其它藻类和微生物菌群表现一定的抑制作用,蓝纤维藻和小环藻等少数藻种可与拟柱胞藻形成共优势种.拟柱胞藻为广东珠三角凡纳滨对虾低盐度虾池重要优势藻种,且以螺旋型为主.     

武夷山中亚热带常绿阔叶林样地的群落特征

武夷山保存了典型的中亚热带原生性森林生态系统。由于以往研究的空间和时间尺度较小, 方法规范性不强, 该地区尚缺少大型的、规范的综合性观测和研究平台。本文依托环境保护部南京环境科学研究所等单位按照CTFS调查技术规范建立的武夷山中亚热带常绿阔叶林9.6 ha动态监测样地开展植物群落调查, 从物种组成、区系特征、径级结构和空间分布格局等方面分析了其群落特征。结果表明: 样地内有维管植物68科135属232种, 其中乔木层内胸径≥ 1 cm的植物有44科86属171种。热带性质的科和属分别占总科数和总属数的68.58%和58.83%, 热带特征明显。珍稀濒危物种较多, 有4种国家II级重点保护野生植物、2种《中国生物多样性红色名录——高等植物卷》中的“近危”物种、1种《濒危野生动植物种国际贸易公约》(CITES)附录II物种以及72种中国特有物种, 具有较高的保护和研究价值。稀有种29种, 占总树种数的16.96%。重要值最大的科是壳斗科和山茶科, 二者的重要值之和大于40%。米槠(Castanopsis carlesii)、毛锥(C. fordii)、甜槠(C. eyrei)和少叶黄杞(Engelhardtia fenzlii)的重要值较大, 但没有明显的优势种。小径木较多, 所有个体的平均胸径为5.10 cm, 整体径级分布呈倒J形。乔木层可分为两个亚层, 米槠、毛锥、甜槠等在第I亚层中占优势。米槠和毛锥呈均匀分布, 甜槠、少叶黄杞、赤楠(Syzygium buxifolium)和木荷(Schima superba)呈聚集分布。     

中亚热带同质园不同树种氮磷重吸收及化学计量特征

于2019年8月研究中亚热带同质园11个树种叶片的比叶面积、氮(N)和磷(P)养分重吸收和化学计量特征,分析其养分利用策略.结果 表明:常绿阔叶树种(香叶、香樟、木荷、米槠、醉香含笑和杜英)和常绿针叶树种(杉木和马尾松)成熟叶和衰老叶的比叶面积、N和P含量普遍低于落叶阔叶树种(枫香、无患子和鹅掌楸),而成熟叶片C∶N和...     

Saprotrophy of Conidiobolus and Basidiobolus in leaf litter

This study of the putative saprotrophs of Conidiobolus and Basidiobolus aids the understanding of their ecological roles in litter, and their relationship with the entomogenous fungi of the Entomophthorales. A total of 47 isolates (ten spp.) were screened for their ability to utilise pure compounds, arthropod cadavers, and plant leaf fragments as substrates. Isolates co-occurred in a larch plantation (Larix sp.) or were from adjacent habitats. Of the 21 isolates (nine spp.) tested on potential prime carbon sources, none could utilise common plant structural polymers. Conidiobolus adiaeretus, C. iuxtagenitus, and B. ranarum from litter and some soil isolates of C. heterosporus, C. pumilus, and C. firmipilleus could use starches and glycogen. In marked contrast, all could utilise animal chitin, gelatine, casein, N-acetyl glucosamine, and trehalose. The lipids tributyrin and sunflower oil also supported growth. Conidia on cadavers usually led to high levels of colonisation as was the case for 30 isolates (ten species). Collembola were more frequently and rapidly colonised than mites. Cadavers of many other arthropods were also internally colonised. The ability to utilise cadavers of diverse arthropods indicates that trophic competition between co-occurring test species may be minimal. Niche differentiation may depend more on non-trophic features of their life history. Negative correlation of performance with the presence of naturally occurring, non-test fungi suggests competition with (or antibiosis from) at least some of the other fungi. In washed or unwashed plant fragments of larch litter (F-layer) only occasional local growth and resting spore formation occurred. Extra nutrients did not facilitate colonisation. Alternative forms of repetitional conidia showed a strong association with plant fragments but not with cadavers.     

滨海沙地主要造林树种叶片功能性状及养分重吸收特征

为探讨不同树种对滨海沙地干旱贫瘠环境的适应策略,以滨海沙地主要造林树种木麻黄、湿地松、厚荚相思和尾巨桉为对象,研究了不同树种叶片功能性状及养分重吸收特征.结果表明:阔叶树种(厚荚相思和尾巨桉)的叶面积、比叶面积显著高于针叶树种(木麻黄和湿地松),而针叶树叶干物质含量、叶厚度最高.成熟叶和凋落叶的N、P含量表现为阔叶树高于针叶树,成熟叶高于凋落叶,但凋落叶N∶P较高.针叶树种的N、P养分重吸收效率大于阔叶树种,P重吸收效率明显高于N,木麻黄、湿地松、厚荚相思和尾巨桉的N、P吸收效率分别为64.2%、63.1%、47.0%、16.8%和92.5%、81.6%、80.3%、18.0%.比叶面积与叶片N、P含量呈显著正相关,与叶干物质含量,叶厚度以及N、P养分重吸收效率呈显著负相关;叶干物质含量与叶厚度及N、P养分重吸收效率呈显著正相关.就叶片功能的权衡关系而言,木麻黄和湿地松属于缓慢投资-收益型物种,具有较高的养分重吸收效率,而厚荚相思和尾巨桉属于快速投资-收益型物种,养分的重吸收效率较低.不同滨海沙地造林树种通过叶片功能性状及养分重吸收之间的相互协调实现对滨海沙地特殊生境的适应性.     

中华鬣羚行为谱及PAE编码系统的建立

栖息地破碎化、人为干扰等因素影响着中华鬣羚(Capricornis sumatraensis)的生存。目前, 中华鬣羚的行为研究还比较匮乏, 因此有必要构建中华鬣羚的行为谱及PAE (posture-act-environment)编码系统, 以期促进其基础行为资料的完善, 为深入开展科学研究和保护工作奠定基础。本文旨在: (1)参照国内常用的动物行为编码方法, 以“姿势-动作-环境”为轴心, 建立中华鬣羚的行为谱及PAE编码系统, 并随机抽取20%的中华鬣羚视频作为检测样本, 对行为谱的实际使用效果进行测试。(2)对中华鬣羚的行为数据进行统计并通过计算行为多样性指数, 分析各特定年龄组间的行为多样性差异, 检验特定年龄组与行为多样性指数间的相关性。结果显示: (1)通过区别和归类中华鬣羚的10种姿势、80种动作、9种环境、78种行为, 首次建立了中华鬣羚的行为谱及PAE编码系统。经测试, 该行为谱能够客观地对中华鬣羚行为进行识别和归类。(2)与亚成体和幼体相比, 中华鬣羚成体特定行为类型的行为多样性指数(A_variable)、绝对行为多样性指数(A)、相对行为多样性指数(r)和校正行为多样性指数(r-variable)均为最高; 中华鬣羚亚成体特定行为类型的行为多样性指数(A_variable)、绝对行为多样性指数(A)、相对行为多样性指数(r)介于成体和幼体之间; 中华鬣羚幼体的特定行为类型的行为多样性指数(A_variable)、绝对行为多样性指数(A)和相对行为多样性指数(r)最低, 校正行为多样性指数(r-variable)高于亚成体。(3)中华鬣羚行为谱可用于其行为学研究, 今后应获取繁殖行为的图像数据, 更新行为谱及PAE编码系统。(4) 3个特定年龄组中华鬣羚的各行为多样性指数之间差异不显著(F = 0.013, P = 0.987), 从幼体到成体, 中华鬣羚的特定行为类型的行为多样性指数(A_variable)、绝对行为多样性指数(A)和相对行为多样性指数(r)随年龄的增大呈递增趋势。综上所述, 我们应深入研究中华鬣羚行为学, 为其保护工作提供科学支撑。     

亚热带树种转换对林地土壤微生物群落结构和功能的影响

通过分析杉木采伐迹地营造阔叶树种尾巨桉和固氮树种黑木相思人工林后土壤微生物群落组成和酶活性,探讨造林树种转换对于改善杉木林地土壤微生物特性的影响.结果表明: 树种转换对土壤微生物群落组成和酶活性的影响主要局限于0～10 cm土壤层.杉木转换为固氮树种黑木相思后,显著提高了0～10 cm土壤层总脂肪酸含量、真菌、革兰氏阳性细菌、革兰氏阴性细菌和放线菌生物量.主成分分析表明,黑木相思人工林土壤微生物群落组成与杉木和尾巨桉人工林具有显著差异,土壤中革兰氏阳性细菌、阴性细菌和放线菌丰度显著提高.在0～10 cm土壤层,黑木相思人工林土壤纤维素水解酶、乙酰氨基-葡萄糖苷酶和酸性磷酸酶活性均显著高于杉木和尾巨桉人工林.研究表明,杉木转变为固氮树种黑木相思后会显著提高微生物生物量和酶活性,有助于土壤有机质的恢复,加快养分循环过程.     

舌鳎亚科鱼类单系起源和同种异名的线粒体DNA证据

舌鳎亚科鱼类因形态特征的特殊性, 其分类及系统发育关系一直存在争议。本研究测定了中国沿海14种舌鳎亚科鱼类线粒体DNA的16S rRNA和Cyt b基因的部分片段。两个基因构建的舌鳎亚科系统发育树结果显示, 中国沿海舌鳎亚科鱼类为明显的单系群, 但舌鳎亚科鱼类内部的系统发育关系与形态分类划分的亚属并不完全一致, 日本须鳎(Paraplagusis japonica)与其他舌鳎属(Cynoglossus)种类并未形成不同的分支。虽然舌鳎属内的舌鳎亚属(Cynoglossus)、拟舌鳎亚属(Cynoglossoides)和三线舌鳎亚属(Areliscus)均可以聚为独立分支, 但长吻红舌鳎(C. lighti)与短吻红舌鳎(C. joyneri)、短吻三线舌鳎(C. abbreviatus)与紫斑舌鳎(C. purpureomaculatus)、半滑舌鳎(C. semilaevis)与窄体舌鳎(C. gracilis)及褐斑三线舌鳎(C. trigrammus)这三组物种可能存在同种异名现象。这一结果提示, 基于形态学对舌鳎亚科的种属分类鉴定尚存在不足, 线粒体DNA的系统发育关系可为其分类的修订提供有意义的参考和佐证。     

A yeast clade near Candida kruisii uncovered: nine novel Candida species associated with basidioma-feeding beetles

Yeasts similar to Candida kruisii were isolated repeatedly from the digestive tracts of basidioma-feeding beetles, especially nitidulids inhabiting and feeding on a variety of agarics in the southeastern USA and Barro Colorado Island, Panama. Based on the identical sequences of the D1/D2 domains of the LSU rRNA gene (rDNA) and host beetle information, the isolates were grouped into 19 genotypes which varied from C. kruisii by up to 38 nucleotide differences in the D1/D2 region. Phylogenetic analysis of rDNA sequences and phenotypic traits placed the isolates in C. kruisii and in nine undescribed taxa. The new species and type strains are designated as Candida pallodes (NRRL Y-27653^T), C. tritomae (NRRL Y-27650^T), C. panamensis (NRRL Y-27657^T), C. lycoperdinae (NRRL Y-27658^T), C. atbi (NRRL Y-27651^T), C. barrocoloradensis (NRRL Y-27934^T), C. aglyptinia (NRRL Y-27935^T), C. stri (NRRL Y-48063^T), and C. gatunensis (NRRL Y-48064^T). A phylogeny based on analysis of a combined database of sequences of SSU and LSU rDNA and the ITS region showed that the nine new species formed a novel sister clade to C. kruisii that was strongly supported by bootstrap analysis. Candida pallodes, C. tritomae, C. panamensis, and C. lycoperdinae formed one subclade, while C. atbi, C. barrocoloradensis, C. aglyptinia, C. stri, and C. gatunensis formed a second distinct subclade within the larger clade. Candida pallodes and C. atbi showed a strong host specificity to beetle species in the genus Pallodes (Coleoptera: Nitidulidae) collected from a variety of agarics. On the other hand, C. panamensis, C. tritomae, and C. lycoperdinae were associated with several unrelated beetles in Erotylidae, Scarabaeidae, Tenebrionidae, and Curculionidae as well as Lycoperdina ferruginea (Nitidulidae). Candida pallodes, C. tritomae, C. lycoperdinae, and C. atbi have been isolated repeatedly in the USA, while the other five new species have been found only at Barro Colorado Island, Panama.     

多基因联合分析棒束孢属Isaria（Ascomycota,Cordycipitaceae）系统发育关系

对棒束孢属Isaria及近缘属物种开展5基因（nrSSU、nrLSU、tef-1α、rpb1和 rpb2）测序并联合分析,结合GenBank相关类群序列,探讨棒束孢属系统发育关系,最终获得95个菌株、58个明确分类群的2-5基因序列。利用MEGA和MrBayes软件进行多基因聚类分析,结果表明棒束孢属多系起源于虫草菌科中,分3个不同分支。A支主要由Isaria cicadae、I. teniupes、I. coleopterorum、I. fumosorosea和I. cateniannulata等组成;B支包括I. poprawkii、I. locustica、I. javanica、I. amoenerosea和I. cateniobliqua;C支仅有I. farinosa。分支间被Cordyceps militaris、C. ninchukispora、C. pruinosa等隔开。棒束孢在形态上,主要以瓶梗基部膨大、尖端变细及孢子呈链状等特征与其他类群分开,但同时也发现有棒状分生孢子梗和单孢子类型。基于节点的分歧时间预测分析,推测棒束孢属首次分化于70Mya,但棒束孢属主要物种形成却在60-55Mya,且3个分支的棒束孢物种为快速同时形成,而后大多数类群表现遗传稳定。同时发现,与Isaria Clade A较近一支有粉被玛利亚霉Mariannaea pruinosa（C. pruinosa无性型）和蛹草蚧霉Lecanicillium militaris（C. militaris无性型）;与粉棒束孢距离最近一支有Akanthomyces aculeatus（C. tuberculata无性型）和L. attenuatum（C. confragosa无性型）,是两个不同的属征分类群,且相互间遗传距离较近。根据棒束孢属及其近缘种属形态特征的复杂性推测,棒束孢属在快速物种形成中,其近缘类群存在一定程度的丢失和选择性演化。     

宁夏兽类两新纪录——川西缺齿鼩和小纹背鼩鼱

<正>川西缺齿鼩(Chodsigoa hypsibia)(De Winton andStyan,1899)和小纹背鼩鼱(Sorexbedfordiae)(Thomas, 1911)同属于劳亚食虫目(Eulipotyphla)鼩鼱科(Soricidae)。缺齿鼩鼱属(Chodsigoa,Kastschenko, 1907)全世界目前已知10个物种(Wilson and Mittermeier, 2018; Chen et al., 2022)，其中川西缺齿鼩为中国特有，     

Sexual dimorphism in Champsosaurus (Diapsida, Choristodera)

Two nearly complete specimens of Champsosaurus (Diapsida, Choristodera) with distinctive morphologies, from the Tullock Formation (Early Paleocene) of northeastern Montana, USA, were described as different species. The limb bones of C. ambulator are more robust than those of C. laramiensis, indicating that C. ambulator was more adapted for walking than C. laramiensis. The phylogenetic significance of these limb bone morphologies, however, appears questionable because similar dimorphic variations occur in a closely related genus and champsosaurs from other geologic ages and locations. Female champsosaurs may have been better adapted to a terrestrial life than males due to nesting behavior on land, resulting in variable limb bone morphologies between sexes. The observed morphologic variations are, hence, hypothesized to reflect sexual dimorphism rather than sympatry of species. The C. ambulator-shaped humeri and femora, demonstrating a terrestrial adaptation, are suggested to belong to females and C. laramiensis-shaped limb bones to males. No significant variations of humeral and femoral morphologies occur in small champsosaur specimens, suggesting an aquatic niche for juveniles like adult males.     

Cryptococcus zeae, a new yeast species associated with Zea mays

A new yeast, Cryptococcus zeae (type strain HB 1207^T) is described. Six strains were isolated from corn and pests of corn in Austria. Microsatellite-primed polymerase chain reaction (MSP-PCR) fingerprints showed that the strains are members of the same species. Phylogenetical analyses of domains D1/D2 26S rDNA and ITS 1-5,8S–ITS 2 sequences showed C. zeae to have the closest relationship to C. luteolus. The D1/D2 sequences of C. zeae fit with three Korean Cryptococcus sp. strains (AF459690, AF459691, AF459692). The new species is separable from the closest relative C. luteolus using only two physiological tests.     

Microhabitat selection in intertidal gobiid fishes: Species- and size-associated variation

Patterns of space use and the individual-based behaviour of microhabitat selection were investigated in three intertidal gobiid fishes, Bathygobius fuscus, Chaenogobius annularis and C. gulosus, from Kyushu, southern Japan. While the three species tended to occupy slightly different types of tidepool, their patterns of distribution largely overlapped in the field. Laboratory experiments involving choice of shelter (i.e. underneath a stone plate) and four different substrate types were conducted to examine size- and time-related variation in habitat selection. The shelter area was preferred by small- and large-sized C. gulosus (day and night), large C. annularis (day and night) and small C. annularis (daytime only), while no preference was evident in small B. fuscus (day and night) and small C. annularis (night). Patterns of substrate choice also differed among species, size groups and between day and night. Size differences in substrate use were evident in B. fuscus and C. gulosus but not in C. annularis, while diel differences were shown by all species groups except large B. fuscus. The gravel and sand substrates tended to be used more frequently than the bare rock substrate, but the strength of preference of a particular substrate type varied among individuals/species. Our results demonstrate that habitat selection by the three gobiid species is variable depending on species, body size and time of day, which must ultimately bear upon mitigating intra-/interspecific interactions in tidepool environments.     

蛹虫草病原真菌虫草生齿梗孢Calcarisporium cordycipiticola的生物学特性研究

蛹虫草已经成为我国乃至东南亚地区极其重要的食药用真菌,虽然其子实体已经实现规模化生产,但在产业发展中遇到许多问题,真菌病害为其中之一,如引起蛹虫草“白毛病”病害的虫草生齿梗孢Calcarisporium cordycipiticola。本研究以虫草生齿梗孢为对象,研究了其生物学特性、发病特性及侵染特点。结果表明：该病原菌菌丝分枝较多,短时间内产生大量分生孢子;最适生长温度为25℃,此温度有利于该病害快速传播;其分生孢子比蛹虫草分生孢子耐紫外能力强。栽培过程中该病害多发生在蛹虫草生长发育后期,可以侵染培养基表面、子实体底部、中部和顶端等各个部位。人工接种发现该病原菌可以侵染蛹虫草生长发育的任意阶段,后期子实体被白毛覆盖。对峙实验发现虫草生齿梗孢菌丝逐渐生长到蛹虫草菌丝上,但未发现两菌丝互相缠绕的现象。对该病原菌基本生物学研究,将为建立该病害的早期检测及预防方法提供依据。     

Phylogenomic analysis clarifies the evolutionary origin of Coffea arabica

Interspecific hybridization events have played a major role in plant speciation, yet the evolutionary origin of hybrid species often remains enigmatic. Here, we inferred the evolutionary origin of the allotetraploid species Coffea arabica, which is widely cultivated for Arabica coffee production. We estimated genetic distances between C. arabica and all species that are known to be closely related to C. arabica using genotyping-by-sequencing (GBS) data. In addition, we reconstructed a time-calibrated multilabeled phylogenetic tree of 24 species to estimate the age of the C. arabica hybridization event. Ancestral states of self-compatibility were also inferred to shed new light on the evolution of self-compatibility in Coffea. Coffea canephora and C. eugenioides were confirmed as the putative progenitor species of C. arabica. These species most likely hybridized between 1.08 million and 543 000 years ago, coinciding with periods of environmental upheaval, which may have induced range shifts of the progenitor species that facilitated the emergence of C. arabica.