The earliest fossil evidence of the Hamamelidaceae: Late Cretaceous (Turonian) inflorescences and fruits of Altingioideae

Fossilized pistillate inflorescences, fruits, and pollen grains from the Turonian (～90 million years before present) of New Jersey are described as a new genus, Microaltingia, in the family Hamamelidaceae. The fossils are remarkably preserved in exceptional detail. Several morphological and anatomical characters suggest affinities with Hamamelidaceae. These include capitate inflorescences, florets with a hypanthium, two-carpellate gynoecia, perigynous flowers, tricolpate reticulate pollen, a three-layered carpel wall, scalariform perforation plates with oblique end walls, and scalariform and opposite/alternate intervascular pitting. The gross morphology of pistillate inflorescences, unisexual flowers, phyllome structure, numerous ovules per carpel, and mode of carpel dehiscence indicate affinities with subfamily Altingioideae, which includes the modern genera Liquidambar and Altingia. Cladistic analysis using a previously published morphological matrix and scoring the fossil for available characters supports the position of the fossil as a sister taxon of modern Altingioideae. Although the fossil exhibits a mosaic of characters found within modern Hamamelidaceae, it is not identical to any modern taxon. Based on cladistic analysis, the fossil appears to be a basal "altingioid" that lacks the derived pollen found in extant Altingioideae and retains the more plesiomorphic tricolpate pollen found in the rest of Hamamelidaceae. The floral characters of the fossils, including phyllomes with stomata, short and straight styles, and small perprolate pollen grains, also indicate the possibility of insect pollination.     

Flowers, fruits, seeds, and pollen of Landeenia gen. nov., an extinct sapindalean genus from the Eocene of Wyoming

The new genus Landeenia is recognized on the basis of flowers, pollen, infructescences, fruits, and seeds from the middle Eocene of southwestern and northwestern Wyoming. Landeenia aralioides (MacGinitie) comb.nov. has cymose inflorescences with actinomorphic, bisexual flowers, a pentamerous calyx, about ten stamens, and a superior gynoecium of ～18 carpels sharing a single style. The fruits are globose to oblate, loculicidally dehiscent capsules, with a persistent calyx, and contain flat, elliptical seeds that are surrounded by a small wing. Pollen removed from the anthers is tricolpate with finely striate sculpture. Although clearly dicotyledonous, the combination of characters found in Landeenia is not known in any modern genus. The familial affinities of the plant, though certainly not with the Araliaceae as previously thought, remain uncertain. However, the combination of characters is consistent with treatment as a member of the Sapindales. The fossil material is thus assigned to the rank of Sapindales-Incertae sedis.     

On the Systematic Position of Daphniphyllaceae

The present paper deals with the systematic position of Daphniphyllaceae. The genus Daphniphyllum was first described by Blume in 1826 as a member of Rhamnaceae. In 1858 Baillon removed it to the tribe Phyllantheae of Euphorbiaceae, while Müller (1869) raised this genus to the rank of family, Daphniphyllaceae. Although Müller’s treatment has been accepted by most botanists, including the present authors, its systematic position has been debated. The first aim in our studies on the cladistics of Hamamelidae is to answer the question which families should be included in this monophyletic group. By observing their pollen grains and stoma types of some representative species of Daphniphyllaceae, Hamamelidaceae and Buxaceae under light microscope (LM) and scanning electron microscope (SEM,) and analysing morphological, anatomical, palynological, embryological characters and chemical components in the three taxa and Euphorbiaceae, we find that Daphniphyllaceae is very similar to Hamamelidaceae, but greatly different from Euphorbiaceae, in inflorescence racemose or spicate, calyx nearly reduced, stamens numerous and sometimes synandry, connective usually exserted, disc absent, carpels 2; vessel with scalariform perforation plates and often not spiral-thickened, fiber bordered-pitted; stomata mostly paracytic; pollen 3-colpate; tapetum glandular, endosperm development cellular, obturator and caruncle absent; iridoid compounds present; sieve-element plastids S-type. The present authors have noticed the fact that Daphniphyllaceae is also similar to Magnoliaceae in the stamens numerous, anthers larger and filaments very short, connectives obviously exserted and with several bundles; anther wall thicker, endosperm development cellular, embryo small. It is considered that not only are Daphniphyllaceae and Hamamelidaceae phenetically close to each other but also much possibly derived from a common ancestor, the extinct group of Magnoliales. However, Daphniphyllaceae appears to be remote from Euphorbiaceae and Buxaceae in relationship and should be separated from Euphorbiales and Buxales. Meanwhile, since Daphniphyllaceae differs from the members of Hamamelidales in the incompletely septate ovary, drupaceous fruit, indistinct sexine sculpture of pollen grains, small embryo, and an unique alkaloid, daphniphylline, but lacking proanthacyanins, the establishment of an order, Daphniphyllales, for the family, is considered reasonable. According to our opinion, the order is related to Hamamelidales rather than to Euphorbiales as originally suggested by Huru-sawa (1954).     

Distyly and pollen dimorphism in<Emphasis Type="Italic"> Damnacanthus</Emphasis> (Rubiaceae)

We document distyly in Damnacanthus (Rubiaceae) and investigate pollen morphology in the genus. Within nine taxa in Japan (four species, four varieties and one form), five show distyly. Non-distylous taxa of Damnacanthus always have a long style and short stamens. We examined the pollen morphology of all taxa of Damnacanthus in Japan. The pollen grains of Damnacanthus are 3- to 5-orthocolporate or sometimes loxocolporate. Polymorphic pollen is sometimes observed even within a single flower. Pollen dimorphism is associated with distyly; pollen grains from short-styled (thrum) flowers are significantly larger than those from long-styled (pin) flowers, and the muri are smooth in pin flowers whereas the pollen grains of thrum flowers have minute granules on the top and/or on the sides. In non-distylous taxa, in which the style is longer than stamens, the muri are always provided with minute granules. Interestingly, the pollen grains with granules in the non-distylous taxa contrast with the pollen of the distylous taxa, because granulate pollen grains are found only in thrum flowers. Although Damnacanthus is a stenopalynous genus, the number of colpi is useful for delimiting taxa. Based on palynological characters, we conclude that Damnacanthus should be revised. Electronic Publication     

<Emphasis Type="Italic">Lepidagathis danielii</Emphasis> (Acanthaceae), una especie nueva de la Cuenca del Río Balsas en el Estado de Guerrero,México

A new species from the Balsas river basin in Guerrero state, Mexico, is described and illustrated: Lepidagathis danielii (Acanthaceae). This new species is distinguished from all the known species of the genus because it has leaves and bracts with an apical spine, inflorescences with decussate flowers, a calyx with connate lobes of equal length, a red corolla that is 3 cm long and conspicuously bilabiate with a constriction near the base where the stamens are also inserted. In addition, the style is covered with scattered trichomes and the pollen is tricolporate without pseudocolpi.     

A taxonomic reassessment of Blepharocarya F. Muell.

The specialized female and male inflorescences of Blepharocarya are analysed revealing that each is derived from a thyreoid inflorescence. This appears to be a characteristic of the Anacardiaceae. The occurrence of vertical intercellular secretory canals in the primary and secondary phloem is illustrated, whilst the presence of Rhus–type pollen is confirmed. These characters provide further support for the retention of the genus in the Anacardiaceae.     

Pollen Morphology in the Subtribe Aspidistrinae (Liliaceae s. l.)

Pollen morphology in the subtribe Aspidistrinae is reported and the main viewpoints are summarized as follows: (1) Two major types of pollen grains, i.e., monosulcate,ellipsoidal pollen and inaperturate, spheroidal pollen, are identified in the genus Tupistra. The species with monosulcate, ellipsoidal pollen usually have monomodal karyotypes, brightcolored flower, smaller stigma, and stamens inserted at upper or middle part of perianth tube, while the inaperturate and spheroidal pollen is always found in the species with bimodal karyotypes, dingy-colored flower, swollen stigma and stamens inserted at the base of perianth tube. (2) Pollen grains in the genus Rhodea are monosulcate and ellipsoidal, while those in the genus Aspidistra are inaperturate and spheroidal, correspondingly similar to the second type of pollen grains in the genus Tupistra. (3) The most primitive pollen in the subtribe Aspidistinae is regarded as monosulcate and ellipsoidal, having perforate or reticulate exine sculpture. The inaperturate, spheroidal pollen with verrucate, gemmate or rugulate exine sculpture is considered derived; (4) Unlike those reported in other groups of the family Liliaceae, the infraspecific pollen shape, aperture type and exine sculpture in Aspidistrinae are basically stable and may serve as a taxonomic character.     

Numerical analysis study of pollen grain populations of Eryngium Maritimum L. (Umbelliferae)

Statistical and numerical taxonomic methods reveal two groups of pollen populations in one plant of Eryngium maritimum L. growing at Noordwijk aan Zee (The Netherlands); one group includes the tertiary and primary lateral inflorescences which possess inhibited growth; the other group comprises the secondary lateral inflorescences showing normal growth. The effects of the physiological inhibition mechanism are complex and are shown by many pollen characters— the dimensions of P (polar axis) and E (equatorial diameter), the presence of a thickening of the exine in the intermediate zone, the shape of the internal contour of the endexine, etc. The differentiation of two types of pollen populations has not only taxonomic interest at the individual, locality, or species level, but also physiological significance. The shape of the internal contour of the endexine, which is a very important feature of “macroevolution” of pollen types in Umbelliferae (Cerceau-Larrival), is directly influenced by the inhibited growth.     

Reproductive structures of an extinct platanoid from the early Cretaceous (latest Albian) of eastern North America

Two new species of platanoid reproductive structure are described from the Bull Mountain locality in the Patapsco Formation (Potomac Group) of northeastern Maryland, USA. Pistillate inflorescences and infructescences (Platanocarpus elkneckensis sp. nov.) consist of flowers and fruits in sessile globose heads that are borne on an elongate axis. Individual pistillate flowers consist of five free carpels surrounded by prominent tepals. Staminate inflorescences, flowers and isolated stamens are assigned to Hamatia elkneckensis gen. et sp. nov. Staminate flowers are borne in a globose head with a small number of stamens (five?) per flower. Stamens consist of very short filaments, long anthers with strongly valvate dehiscence and an apically expanded connective. The connective expansion is frequently very well-developed, hook-like and extends down the ventral surface of the stamen. Anthers contain small, tricolporate, reticulate pollen. Association evidence, similarity of inflorescence structure and the occurrence of Hamatia-type pollen on flowers, carpels and fruits of Platanocarpus elkneckensis suggests that the staminate and pistillate material was produced by a single species of plant. The “Hamatia-plant” provides further evidence of pentamerous floral structure in mid-Cretaceous platanoids and documents the occurrence of unequivocal tricolporate pollen in the platanoid complex.     

Fossil floral structures of a basal angiosperm with monocolpate,reticulate-acolumellate pollen from the Early Cretaceous of Portugal

Distinctive monocolpate and reticulate-acolumellate pollen grains with a coarse, loosely attached reticulum have long been known as a conspicuous element of many palynological assemblages from the Early and mid-Cretaceous. These grains are now described in situ in staminate structures and on the surface of pistillate organs from two Early Cretaceous (Barremian or Aptian) mesofloras from Portugal (Vale de Agua and Buarcos). Staminate organs include a staminate axis with spirally arranged stamens and many isolated stamens. Stamens consist of a short filament, a dithecate, tetrasporangiate anther, and a short apical extension of the connective. Anther dehiscence is extrorse by longitudinal slits and in situ pollen is monocolpate, semi-tectate with a coarse, loosely attached reticulum composed of narrow muri with a spiny ornamentation. The infratectal layer of the pollen wall is thin, granular, and lacking columellae; and the foot layer is distinct. The endexine is thin, except under the aperture where it is thick. The pistillate organs are minute consisting of a simple unilocular ovary containing a single thin-walled seed. Associated with staminate and pistillate structures are many coprolites consisting almost exclusively of pollen grains of this distinctive type. The staminate and pistillate organs are not found in organic connection, and two new genera are established to accommodate the new floral structures: Pennistemon comprising the staminate structures and Pennicarpus comprising the pistillate structures. A new genus, Pennipollis, is also established for the dispersed grains, based on the type species Peromonolites peroreticulatus Brenner, since no appropriate genus has yet been described for these acolumellate grains. Features of the pollen grains strongly indicate affinity with members of the Alismatales and characters of the mesofossils also support this assignment. This is the first record of putative monocots in the early Cretaceous based on combined pollen and floral features.     

蜘蛛抱蛋亚族的花粉形态

本文研究并报道了百合科蜘蛛抱蛋亚族的花粉形态,主要结论如下：1．开口箭属含两种花粉类型即：(1)单槽、椭圆形;(2)无萌发孔、球形。具单槽、椭圆形花粉的种类含单型性核型,花形较小,柱头小而花柱短,雄蕊高于柱头;无萌发孔、球形花粉的种类则为单型性核型,花形较大,柱头常高度膨大,雄蕊常着生在花被筒基部。2．万年青属花粉为椭圆形,具单槽;蜘蛛抱蛋属花粉则为球形,无萌发孔;开口箭属花粉一部分与万年青属相似,另一部分则与蜘蛛抱蛋属雷同。3．蜘蛛抱蛋亚族中最原始的花粉类型为单槽椭圆形,具孔状或网状外壁纹饰。球形,无萌发孔,外壁具皱波状、瘤状或芽孢状纹饰的花粉为派生类型。4．蜘蛛抱蛋亚族种下花粉形状、萌发孔类型和外壁纹饰基本稳定,可作为分种特征。     

Beiträge zur Kenntnis der Sippenstruktur des Genus Parabarium Pierre ex Spire (Apocynaceae)

The genus Parabarium is clearly separated from the other genera of the subtribe Urceolinae by different characters. The inflorescences of their taxa are heterocladical pleiothyrses, trunk synflorescences, or pleiochasiums. Further morphological and anatomical investigations deals with flower buds, leaves, pollen grains, fruits, seed, and other parts of the plants. Basing on the character analysis resulting from this the genus Parabarium is divided into two subgenera with two sections and two subsections enclosing 16 species. Two of the latter are described as news, further two varieties are set up as new ones. Two species are transferred from the genus Ecdysanthera into the genus Parabarium. Further three Parabarium species are inserted, and some more taxonomical corrections are made. — The possible relations within the genus Parabarium are made. Based on these results P. micranthum and therefor the subsection Parabarium (subgenus Parabarium) have to be regarded as the more original ones in face of P. quintaretii and the subgenus Pleiochasium. The section Burmanicum of the subgenus Parabarium has an exceptional position within the genus     

A synopsis of the genus <Emphasis Type="Italic">Poteranthera</Emphasis> (Melastomeae: Melastomataceae) with the description of a new,apparently pollinator deceiving species

A synopsis of the annual genus Poteranthera is presented here. Three species are recognized including the newly described Poteranthera windischii. Poteranthera is characterized by its annual life cycle, generally linear leaves that have conspicuous gland-tipped hairs on the lamina margin, 5-merous flowers with a constriction at the level of the torus, one cycle of stamens reduced to staminodia or absent altogether, three locular ovary, and reniform seeds with a foveolate testa. The flowers of the new species P. windischii are strongly heterandrous, where the usual set of stamens that bees harvest pollen from is reduced to staminodia and the stamen set that deposits pollen on the bee has large yellow ventral appendages that possibly function as pollen mimics and result in deceit pollination. This hypothesis is supported by experiments that have demonstrated innate preferences of female bees for yellow, UV absorbing colors in flowers. Species of Poteranthera are extremely rare, known from very few specimens and possibly highly endangered.     

Studies on the Genus Schizopepon Maxim. (Cucurbitaceae)

The classical and numerical taxonomy, palynology and the geographical distribution of the Genus Schizopepon are dealt with in the present paper. Having commented on various opinions regarding the systematic position of the genus, the present authors consider that C. Jeffrey’s treatment of Schizopepon as a new and monogeneric tribe, Schizopeponeae, should be supported. The gross morphological characters in the genus are assessed from the taxonomic point of view. Some characters, such as stamens with an elongated connective or not, different insertions of ovules and various forms of ovaries and fruits, may be used for distinguishing subgenera. The pollen grains of all the species were observed under light microscope (LM) and scanning electron microscope (SEM). The results show that a strong differentiation has taken place in the pollen of the genus, and in consequence it may be regarded as an important basis for dividing subgenera and species. Especially it should be pointed out that degrees of development of colpi and positions of ora are positively correlated with the external characters used for distinguishing subgenera. According to the morphological and palynological characters, the genus Schizopepon may be divided into three subgenera and eight species: 1. Subgenus Schizopepon: 5 species, S. bryoniaefolius Maxim., S. monoicus A. M. Lu et Z. Y. Zhang, S. dioicus Cogn., S. longipes Gagnep. and S. macranthus Hand.-Mazz.; 2. Subgenus Rhynchocarpos A. M. Lu et Z. Y. Zhang: 1 species, S. bomiensis A. M. Lu et Z. Y. Zhang; 3. Subgenus Neoschizopepon A. M. Lu et Z. Y. Zhang: 2 species, S. bicirrhosus (C. B. Clarke) C. Jeffrey and S. xizangensis A. M. Lu et Z. Y. Zhang. The 8 OTU’s including all the species of this genus and 31 characters, of which 16 are morphological characters and 15 palynological characters, were used in the numerical taxonomic treatment. After standardization of characters, the correlation and distance matrices were computed. The correlation matrices are made to test the various clustering methods. At last, the UPGMA clustering method was selected and its result is shown in the form of phenogram. The result of numerical analysis is similar to that of the classical classification. Schizopepon Maxim. is a genus of East Asia-Himalayan distribution. China has all 8 species and 2 varieties, of which 6 species are endemic. Based on the statistics of spedies number, the distribution centre of the genus is considered to be in the Hengduan Mountains (Yangtze-Mekong-Salwin water divides) and the adjacent areas of the southwest China.     

A Study on the System of Lindera

This paper is an attempt to discuss the relationship and phylogeny within the genus Lindera, based upon on analysis of shortened brachlets, on which the inflorescences are inserted, and other morphological characters. The shortened branchlets are metamorphic shoots which are often at the transitional stage between branchles and inflorescences. The advanced shortened branchlets usually with an undeveloped terminal bud, posses scale-like leaves, and the inflorescences so formed are sessile and aggregate. In primitive taxa, such as Lindera nacusua (Don) Merr., L. gracilipes H. W. Li and L. tanchuanensis Feng et H. S. Kung, the branchlet is usually not shortened, with well-developed terminal bud, forming a single axillary pseudo-umbel, while its peducle is usually very slender and stamens of pistillate flower sometimes more or less developed. The leaves on the upper part of branchlet are normal and the lower part of branchlet becoming bracteal, In the genus the development of shortened branchlets (Fig. 1.) from the ones in the primitive taxa to the ones in the advanced taxa may be found. Other important morphological characters are the length of peducles. The peduncle is usually slender in the primitive taxa, short or even sessile in the adanced taxa. There are two types of venation in the genus: the pinnate and trinerved. As the primitive group trib. Perseeae Mez shows pinnate veins, pinnate ventation in Lindera is more primitive than trinerved one. It might be possible that a transition occure in the genus from evergereen habit to deciduous one as shown in Lindera glauca B1., L. angustifolia Cheng and L. praecox B1., whose leaves tardily wither but persistent over winter. The relationships within Lindera are shown in a hypothetical genealogical tree (Fig. 4), which includes the system of Litsea, developed parallelly with Lindera. From the study of morphological characters, the author infers that both Lindera and Litsea have originated from a common ancestory related to the tribe Cinnamomeae Baill. which has a single axillary inflorescence, with hermaphrodite flowers, 4-locular anthers and penninerved to trinerved leaves.     

Reappraisal of Corylopsis trabeculosa (Hamamelidaceae), a Species Endemic to China

The present paper reports the habit,habitat and the morphological characters of inflorescences and flowers of Corylopsis trabeculosa (Hamamelidaceae),a species endemic tothe Dulongjiang Region,Gongshan County, Yunnan Province,China． The morphological comparison supports the opinion that it is an independent species．     

Evolution and homology of bird pollination syndromes in Erythrina (Leguminosae)

Erythrina L. (Leguminosae: Phaseoleae) is a pantropical genus of over 100 species, all of which are either hummingbird or passerine pollinated. Phylogenetic hypotheses based on morphological and chloroplast DNA restriction site characters suggest that shifts from passerine to hummingbird pollination have occurred a minimum of four times in the genus. In hummingbird-pollinated species the inflorescences are held upright, the flowers are arranged radially along the axis, and the narrow standard petal is conduplicately folded to form a pseudotube. In most of the passerine-pollinated species, the inflorescences are held horizontally, the flowers are secund, and the standard petal is open so that the nectar and androecium are easily visible and accessible. Nectar amino acid concentrations and sucrose to hexose ratios are closely associated with pollination mode. Despite the general resemblance in flower and inflorescence morphology among species with the same pollination type, homology assessment reveals that petal morphology and size, and calyx and pollen morphology differ. Morphological characters, even if comprising modifications associated with adaptive pollination systems, therefore provide useful phylogenetic information.     

中国特有植物——俅江蜡瓣花(金缕梅科)的再次确认

本文对我国云南省独龙江地区的特有植物俅江蜡瓣花(金缕梅科)的习性及生境进行了观察,详细地补充描述了该种植物的花序及花部的外部形态特征,确认该种不同于中华蜡瓣花和西域蜡瓣花。中华蜡瓣花的花序较短,长3～5 cm,常具花10～25朵,退化雄蕊5,鳞片状,稍2浅裂,裂片顶端较尖,花柱长6～7mm;而俅江蜡瓣花的花序较长,长3～8cm,常具花20～40余朵,退化雄蕊5,红色,2全裂至基部,裂片10,棍棒状,长o．5～o,6mm,顶端钝,花柱很短,长1．5～2．omm而明显不同于前者。中华蜡瓣花广布于安徽、浙江、江西、湖北、湖南、广东、广西、及贵州等地,而俅江蜡瓣花则仅局限地分布于云南省贡山县独龙江地区的中海拔山地。因此,我们支持将俅江蜡瓣花作为一独立的种的处理。     

CHLORANTHUS-LIKE STAMENS FROM THE UPPER CRETACEOUS OF NEW JERSEY

Fossil angiospermous stamens with in situ pollen from the Turonian (ca. 90 million years before present, Late Cretaceous) of New Jersey are described and assigned to the Chloranthaceae. The fossil stamens, which are three-parted and bear two bisporangiate thecae on the central lobe and one bisporangiate theca on each lateral lobe, are indistinguishable from stamens of several extant species of Chloranthus. The pollen is spheroidal, 13–18 μm in diameter, with a reticulate exine and apparently elongate/elliptical apertures. The pollen is similar to that in extant Chloranthus in grain size, shape, exine sculpture, and aperture structure. Like pollen of some extant species of Chloranthus, aperture number in the fossil pollen appears to be variable. Because fossil pistillate chloranthoid reproductive structures have not been found at this locality it is unknown whether the fossil stamens described here were borne on the side of the ovary, as in extant Chloranthus, or in another arrangement. The three-parted stamen of Chloranthus is unique in angiosperms and there has been considerable debate concerning the origin and evolutionary significance of the structure. Uncertainty as to whether the three-parted stamen represents a synapomorphy for the genus or a retained plesiomorphy in angiosperms is the primary reason why these fossil stamens are not assigned to the extant genus Chloranthus.