锦葵目蚬木属和柄翅果属的木材解剖学研究及其系统学意义

蚬木属(Excentrodendron H.T.Chang & R.H.Miau)与柄翅果属(Burretiodendron Rehder)的分离一直未得到广泛认同,二者在锦葵目中的系统地位也还不十分清楚.本文研究了柄翅果、元江柄翅果、滇桐和火绳树的木材解剖.柄翅果和元江柄翅果在木材解剖特征上非常相似,2～3个管孔组成径列复管孔,单管孔较多,导管分子无螺纹加厚,穿孔板单一,轴向薄壁组织稀少,射线异型IIB,单列射线少,多列射线常2～3列,具翅子树属型瓦形细胞;蚬木属单列射线罕见,瓦形细胞榴莲型,单列射线较高,木材解剖特征支持蚬木属和柄翅果属的分离;蚬木属和柄翅果属与滇桐属在木材解剖特征上差异显著,与火绳树属的差异也较明显,但与梧桐科翅子树属比较接近,与其它有关类群,如一担柴属、Luehea、Entelea以及Dombeyeae族等都有明显差异.     

梧桐科翅子树属的亲缘关系

翅子树属传统上均作为梧桐科山芝麻族的成员,但也有少数人将它归到Dombeyeae族中。本文根据对翅子树属的外部形态及花粉形态特征的研究,并结合其解剖、染色体和胚胎发育的资料,对翅子树属的亲缘关系进行了分析。翅子树属与山芝麻族在外部形态上比较接近,但在解剖、花粉形态和染色体基数等特征上则差异显著;与Dombeyeae族在花粉形态上一致,但在外部形态(花结构)、染色体基数和瓦形细胞等特征方面则明显不同,反映了翅子树属在这两个族之间的过渡状态,不宜作为任何一族的成员,应该作为一个独立的族存在,其在梧桐科中的位置在Dombeyeae附近。     

蚬木的大孢子发生与胚囊发育兼论蚬木属的系统亲缘

蚬木Excentrodendron hsienmu雌雄花在发育早期均有小孢子和大孢子的早期发育, 难以区分。蚬木子房5室, 具中轴胎座, 每室2胚珠; 胚珠倒生, 厚珠心, 双珠被, 成熟胚囊内珠被3层细胞, 外珠被3-4层细胞, 内外珠被共同形成之字形珠孔; 单细胞孢原, 大孢子四分体主要为线形, 稀为T形, 通常合点端大孢子为功能大孢子, 胚囊为蓼型; 在大孢子发生和胚囊发育时期有退化现象, 成熟胚囊时期退化率和种子退化率分别达88%和91%。蚬木属Excentrodendron在内外珠被层数上与柄翅果属Burretiodendron明显不同, 也与翅子树属Pterospermum、非洲芙蓉族Dombeyeae不同。蚬木属与柄翅果属的分离一直没有得到广泛接受, 但胚胎学证据支持蚬木属的建立; 与广义锦葵科Malvaceae s.l.其他属胚胎学资料的比较表明, 蚬木属在广义锦葵科中较孤立。     

广义锦葵科火绳树属4个种的枝条木材解剖及其分类学意义

研究了广义锦葵科火绳树属4个种枝条的木材解剖。火绳树属枝条为散孔至半环孔材,管孔主要为单管孔和2～3个管孔组成的径列复管孔;导管间纹孔式和射线导管间纹孔式互列、小;侵填体和螺纹加厚缺如。射线主要为单列射线,2～3列射线较多;射线细胞多为方形,射线组织主要为异型,边缘直立细胞常1行;射线组织稀为同型;鞘细胞和瓦形细胞缺如。轴向薄壁组织傍管和离管型,主要为带状。晶体丰富,主要在射线、纤维和薄壁组织中。研究的4个种可以通过枝条木材解剖特征加以区分。     

葡萄科植物叶表皮特征及其系统学意义

在光学显微镜和扫描电镜下,对葡萄科Vitaceae11属37种代表植物的叶表皮特征进行了观察,发现该科植物叶表皮细胞形状为无规则形或多边形,垂周壁一般为平直、弓形或浅波状;气孔器通常仅分布在下表皮（火筒树属Leea偶尔可在上表皮观察到）,除无规则型（地锦属Parthenocissus、俞藤属Yua、葡萄属Vitis、蛇葡萄属Ampelopsis和酸蔹藤属Ampelocissus）最为常见外,不等细胞型（火筒树属）、短平列型（白粉藤属Cissus、乌蔹莓属Cayratia和崖爬藤属Tetrastigma）、     

9种梧桐科植物叶表皮特征的扫描电镜研究

用扫描电镜对9种梧桐科植物叶片进行观察研究以明确其叶表皮微形态特征差异.结果显示,绝大部分梧桐科植物的气孔类型和气孔形状相似,但其表皮的毛状体类型、形态以及表皮纹饰等方面有显著差异.结果表明9种梧桐科植物的叶表皮毛和表皮纹饰可作为梧桐科种间分类的特征,且研究结果支持将胖大海归属于胖大海属,将翅子树单独列为翅子树族的分类观点.     

利用叶绿体基因组数据解析锦葵科梧桐亚科的系统位置和属间关系

分子系统学研究将传统梧桐科与锦葵科、木棉科和椴树科合并为广义锦葵科,并进一步分为9个亚科.然而,9个亚科之间的关系尚未完全明确,且梧桐亚科内的属间关系也未得到解决.为了明确梧桐亚科在锦葵科中的系统发育位置,厘清梧桐亚科内部属间系统发育关系,该研究对锦葵科8个亚科进行取样,共选取55个样本,基于叶绿体基因组数据,采用最大...     

四棱草属比较形态及其分类系统位置的研究──Ⅳ．四棱草属及其近缘属叶表皮结构特征

四棱草属Ｓｃｈｎａｂｅｌｉａ及其近缘属筋骨草属Ａｊｕｇａ,香科科属Ｔｅｕｃｒｉｕｍ（唇形科Ｌａｂｉａｔａｅ）,获属Ｃａｒｙｏｐｔｅｒｉｓ,大青属Ｃｌｅｒｏｄｅｎｄｒｕｍ（马鞭草科Ｖｅｒｂｅｒｎａｃｅａｅ）５属,６种代表植物的叶表皮细胞形状、气孔类型和毛状体类型的比较研究结果是：（１）叶上表皮细胞形状是深波纹状不规则形,浅波纹状不规则形和浅波纹状四边形;（２）气孔类型是不规则型,平列型,横列型和等位横列型。（３）毛状体类型属单毛和鳞片毛二种类型。根据上述特征及其分布规律,作者认为四棱草属在唇形科与马鞭草科系统演化的框架里,是处于中间过渡类型的位置。     

中国无患子科的叶表皮特征及其系统学意义

在光学显微镜和扫描电镜下,对狭义无患子科25属33种植物以及七叶树科2种植物和槭树科2属4种植物的叶表皮特征进行了观察,发现这三科植物叶表皮细胞形状为多边形或无规则形,垂周壁一般为平直、弓形或浅波状.气孔器主要有6种类型,通常仅分布在下表皮(倒地铃Cardiospermum halicacabum和伞花木Eurycorymbus cavaleriei偶尔可在上表皮观察到),除无规则型(如波叶异木患Allophylus caudatu、掌叶木Handeliodendron bodinieri、茶条木Ddavaya toxocarpa等16种)最为常见外,辐射型(细子龙Amesiodendronchinense、七叶树Aesculus chinensis、金钱槭Dipteronia sinensis等11种)和环列型(如龙眼Dimocarpus longan、荔枝Litchi chinensis、韶子Nephelium chryseum等6种)也较为普遍,短平列型(赛木患 Aphania oligophylla、绒毛番龙眼Pometia tometttosa、干果木Xerospemuan bonii、假山萝Harpullia cupaniodes)和十字型(广西檀栗Pavieasia kwangsiensis)仅在少数几属中出现,不等细胞型仅出现在倒地铃Cardioslx,mmm halicacabum中.在扫描电镜下,角质层多具有条纹、鳞片或颗粒等特征;三科植物的气孔外拱盖内缘大多为浅波状.本文试图通过对三科的叶表皮特征,尤其是气孔器类型等形态特征的观察,寻求有意义的叶表皮性状,为进一步探讨无患子科尤其是掌叶木属、茶条木属与七叶树科乃至与槭树科亲缘关系提供资料.研究结果从叶表皮特征的角度说明了这三个科在系统上的密切联系.     

广东丹霞山国家级自然保护区 蝙蝠物种多样性调查

于2017年至2018年对广东丹霞山国家级自然保护区的翼手目动物进行调查,主要采用日栖息地与夜栖息地、捕食区网捕等调查方法,共调查到翼手目5科13属23种,其中蝙蝠科(Vespertilionidae)9属15种,菊头蝠科(Rhinolophidae)1属4种,蹄蝠科(Hipposideridae)1属2种,假吸血蝠科(Megadermatidae)1属1种,犬吻蝠科(Molossidae)1属1种。从区系组成来看,以东洋界为主(19种),其次为广布种(3种),古北界仅1种。从栖息类型上看,分为洞栖型、树栖型及建筑物栖息型,以洞栖型为主(15种),建筑物栖息型其次(12种),树栖型最少(5种),但其中9个物种的栖息地类型同时包含了上述3种栖息类型中的2种。本研究在广东丹霞山发现中国蝙蝠新分布记录1种,为卡氏伏翼(Hypsugo cadornae);而中印鼠耳蝠(Myotis indochinensis)为中国分布的再次确认。     

The articular surface of the temporal bone in certain fossil hominoids

Although quantitative variations exist between living Man ( Homo sapiens sapiens ) and the extant great apes ( Pongo, Pan, Gorilla ) in such features of the articular surface of the temporal bone (a part of the temporomandibular joint) as the proportionate development of the postglenoid tubercle, the relative prominence of the articular tubercle and the slope of its posterior face, these do not individually effect a clear differentiation between the four extant genera. But in multivariate combination of these features, although Pan and Pongo are relatively closely associated, Gorilla and Homo sapiens sapiens are distinct, and also clearly differentiated from each other. The differences between genera of extant apes are, on average, as great as those between extant Man and individual apes.
As portrayed by such multivariate compound, this anatomical region in four fossil groups displays a unique configuration differentiating Homo sapiens neanderthalensis, Homo erectus pekinensis, Australopithecus africanus and Australopithecus robustus both from one another and from extant types. The differences are such that the fossil species lie uniquely and not intermediate between extant groups.
Definable age changes in this multivariate compound occur in both Man and apes but neither these, nor overall differences between adults, appear to be associated with marked contrasts in the pattern of jaw movement. It would thus seem improbable that inferences can be made from these features about the type of jaw movement that characterized the several fossil groups.     

Support for an expanded family concept of Malvaceae within a recircumscribed order Mai vales: a combined analysis of plastid atpB and rbcL DNA sequences

Sequence analyses of the plastid genes atpB and rbcL support an expanded order Malvales. Within this alliance, core Malvales are clearly supported and comprise most genera that have previously been included in Sterculiaceae, Tiliaceae, Bombacaceae, and Malvaceae. Additional well supported malvalean alliances include the bixalean clade (Bixaceae, Diego-dendraceae, and Cochlospermaceae), the cistalean clade (Cistaceae, Dipterocarpaceae, and Sarcolaenaceae) and Thymelaeaceae (including Gonystyloideae and Aquilarioideae). Our results indicate sister-group relationships between (1) Neuradaceae and the cistalean clade; (2) Sphaerosepalaceae and Thymelaeaceae; (3) these two clades (1 and 2); and (4) all these and an alliance comprising the bixalean clade and core Malvales, but this pattern is weakly supported by the bootstrap. The affinities of Muntingiaceae and Petenaea are especially ambiguous, although almost certainly they are Malvales s.l. The traditional delimitation of families within core Malvales is untenable. Instead, we propose to merge Sterculiaceae, Tiliaceae and Bombacaceae with Malvaceae and subdivide this enlarged family Malvaceae into nine subfamilies based on molecular, morphological, and biogeographical data: (1) Byttnerioideae, including tribes Byttnerieae, Lasiopetaleae and Theobromeae (all of which have cucullate petals) and Hermannieae; (2) Grewioideae, including most genera of former Tiliaceae; (3) Tilioideae, monogeneric in our analysis; (4) Helicteroideae, comprising most of the taxa previously included in Helictereae, plus Mansonia, Triplochiton (indicating that apocarpy evolved at least twice within Malvaceae) and possibly Durioneae; (5) Sterculioideae, defined by apetalous, apocarpous, usually unisexual flowers with androgynophores; (6) Brownlowioideae, circumscribed as in previous classifications; (7) Dombeyoideae, expanded to include Burretiodendron, Eriolaena, Pterospermum, and Schoutmia; (8) Bombacoideae, corresponding to former Bombacaceae (without Durioneae) but including Fremontodendreae     

Upper Cretaceous woods from the Olmos Formation (late Campanian-early Maastrichtian), Coahuila, Mexico

? Premise of the study: The Olmos Formation was part of a system of deltas that existed in the southern portion of the Western Interior of North America during the Campanian-Maastrichtian. The paleofloristic composition from the northern portions of the Epicontinental Sea is relatively well known, but less intensive exploration in the south has precluded more detailed floristic comparison across the entire latitudinal span of the Sea. The Olmos Formation flora, with more than 100 different leaf morphotypes so far recognized and several wood types, has the most diverse Cretaceous fossil plant assemblage in Mexico and represents a valuable opportunity for comparative studies. ? Methods: The fossil woods here described were collected in the Coahuila State, Mexico. The samples were studied using standard thin section technique and identified by comparison with fossil and extant material. ? Key results: We described four new genera (Olmosoxylon, cf. Lauraceae; Coahuiloxylon, ?Anacardiaceae, ?Burseraceae; Muzquizoxylon, Cornaceae; and Wheeleroxylon, Malvaceae s.l.) and three xylotypes of angiosperms. ? Conclusions: Some of the genera present in the Olmos Formation such as Javelinoxylon and Metcalfeoxylon have been described from geologic units in the USA (San Juan Basin, New Mexico and Big Bend National Park, Texas), suggesting similarity in the taxonomic composition of the floras that inhabited southern portions of the western margin of the Campanian-Maastrichtian Epicontinental Sea. Other species, however, have only been reported for the Olmos Formation, indicating some degree of local floristic differentiation among the assemblages that inhabited the southern portion of the Western Interior.     

CHATTAWAYA (STERCULIACEAE): A NEW GENUS OF WOOD FROM THE EOCENE OF OREGON AND ITS IMPLICATIONS FOR XYLEM EVOLUTION OF THE EXTANT GENUS PTEROSPERMUM

A new sterculiaceous wood, Chattawaya paliformis gen. et sp. n., was collected from a Middle Eocene locality in the type area of the Clamo Formation of north central Oregon. The wood differs from all known extant woods in having very large and irregularly shaped tile cells. However, other features of the xylem indicate a close natural relationship between Chattawaya and the extant paleotropical genus, Pterospermum. It is suggested that the xylem organization of the Eocene fossil represents a more primitive condition than that observed in Pterospermum. Comparative xylotomy indicates three evolutionary trends within the complex to which Chattawaya and Pterospermum belong: development of storied structure, increased uniformity in shape and size of tile cells and loss of multiseriate rays. Chattawaya is part of a growing body of paleobotanical evidence indicating that the Sterculiaceae was well differentiated by the early Tertiary, but that the lineages leading to extant genera have undergone an appreciable amount of evolutionary change since the Eocene.     

Seed morphology of modern and fossil Ampelocissus (Vitaceae) and implications for phytogeography

Seeds are useful in distinguishing among extant genera of Vitaceae and provide a good basis for interpretation of fossil remains in reconstructing the evolutionary and phytogeographic history of this putatively basal Rosid family. Seeds of Ampelocissus s.l. including Pterisanthes and Nothocissus are distinguished from those of all other vitaceous genera by long, parallel ventral infolds and a centrally positioned oval chalazal scar. Principal component analysis facilitates recognition of four Ampelocissus s.l. seed morphotypes differentiated by dorsiventral thickness, width of ventral infolds, chalazal depth, and degree of dorsal surface rugosity. While these intergrade, their end-member morphologies are distinctive and coincide well with inflorescence morphology, extant geographic distribution, and ecology. Seven fossil morphospecies are recognized. Ampelocissus parvisemina sp. n. (Paleocene of North Dakota; Eocene of Oregon) and A. auriforma Manchester (Eocene of Oregon) resemble extant Central American species; A. bravoi Berry (Eocene of Peru) is similar to one group of Old World extant species; and A. parachandleri sp. n. (Eocene of Oregon) and the three European fossil species A. chandleri (Kirchheimer) comb. n., A. lobatum (Chandler) comb. n., and A. wildei sp. n. (Eocene to Miocene) resemble another group of extant Old World Ampelocissus. All these fossils occur outside the present geographic range of the genus, reflecting warmer climates and former intercontinental links.     

The first record of fossil Vitaceae wood from the Southern Hemisphere,a new combination for Vitaceoxylon ramunculiformis,and reappraisal of the fossil record of the grape family (Vitaceae) from the Cenozoic of Australia

Austrovideira dettmannaegen. & sp. nov. from the early Oligocene Capella Flora in central Queensland is the first fossil Vitaceae wood described from the Southern Hemisphere. A new combination, Stafylioxylon ramunculiformis (Poole & Wilkinson) Pace & Rozefelds for a Northern Hemisphere fossil wood is also proposed. Austrovideira and Stafylioxylon share with Vitaceoxylon secondary xylem with two diameter classes of vessels, wide vessels usually solitary, narrow vessels forming radial chains, very wide and tall rays, scanty paratracheal parenchyma and septate fibres. Austrovideira differs from Vitaceoxylon in having scalariform intervessel pits and homocellular rays composed exclusively of procumbent cells. This combination of features is seen in the Ampelocissus‐Vitis clade, and a clearly stratified phloem with fibre bands alternating with all other axial elements and phloem rays rapidly dilating towards the periderm is restricted to Parthenocissus and Vitis. Stafylioxylon shares with Austrovideira the presence of scalariform intervessel pits but it differs from that genus in both ray composition and bark anatomy, as it lacks a stratified phloem. These fossil wood genera demonstrate that the lianescent habit in the Vitaceae was established by the Eocene in the Northern Hemisphere and by the Oligocene in the Southern Hemisphere. The pollen and seed fossil record shows that the Vitaceae were in Australia by the Eocene and fossil seeds suggest that the family had radiated by this time. The Oligocene Capella flora with two seed taxa and fossil wood (Austrovideira) provides further evidence of an Australian radiation. The fossil evidence, suggests a significant Gondwanic history for the family.     

Multicellular-like compartmentalization of cytoplast in fossil larger foraminifera

Foraminifera are usually between 0.1 and 1 mm in size, thus falling within the range of the largest eukaryotic cells. However, some fossil and extant foraminiferal species reach diameters of more than 100 mm. One hypothesis of how these gigantic sizes could have been attained by these unicellular organisms is the temporary compartmentalization of cytoplasm into smaller volumes of effective metabolism, as reported for several recent species. Evidence of this phenomenon is shown in fossil genera of larger foraminifera belonging to five families of Cretaceous to Oligocene age. Alternative interpretations are discussed.     

广西化石猩猩牙齿釉质厚度研究

华南和东南亚发现大量更新世的猩猩牙齿化石。本研究应用CT扫描三维重建的技术方法研究了广西更新世化石猩猩牙齿釉质厚度,并与现生类人猿、现代人、化石类人猿以及早期人类进行比较分析。结果显示:广西猩猩同类牙齿的釉质厚度与牙齿大小相关性很小;臼齿和前臼齿釉质厚度在上下颌之间不存在显著性差异;来自广西不同地区的猩猩化石牙釉质厚度无显著差异。与早期人科成员相比,广西猩猩的牙釉质相对较薄,平均与相对釉质厚度值都明显小于南方古猿、傍人。与早期人属相比,小于直立人、尼人以及非洲和欧洲的早期人属化石。与现代人和现生灵长类相比,广西化石猩猩釉质厚度明显大于大部分猴类和非洲大猿;平均釉质厚度稍大于现生猩猩,而与现代人更为接近;相对釉质厚度小于现代人,而与现生猩猩差异不大,都属于偏厚型釉质。本文讨论了釉质厚度与系统分类演化、食性适应的相关问题,作者推测釉质厚度可能是物种的特征属性,与牙齿功能适应有密切关联。