A new spiny, cushion-like Euphorbia (Euphorbiaceae) from south-west Iran with special reference to the phytogeographic importance of local endemic species

Euphorbia acanthodes Akhani is described as a new gypsophilous species from south-west Iran. The affinity, morphological and carpological features, and habitat of the species are discussed. A list of a further 36 interesting endemic species of south-western Iran and adjacent areas is given with notes on their affinities and distribution. These include Centaurea gudrunensis Boiss. & Hausskn., as a new record from Iran. The specific status of Pteropyrum naufelum Al-Khayat is confirmed and it is suggested that P. noëanum Boiss. ex Meisn. is synonymous with P. aucheri Boiss. The biogeographic importance of the so-called 'Persian foothills', and biodiversity conservation status of the area are discussed, together with distribution maps of 12 species. It is concluded that the majority of the endemic species in the southern and south-western parts of Iran are Irano–Turanian or have their origins in the Irano–Turanian region. Therefore, it is questionable to consider the area as part of either the Saharo–Sindian, Sudanian or Sudano–Zambezian regions.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 107–121.     

LATE CRETACEOUS FOSSIL FLOWERS OF ERICALEAN AFFINITY

Fossilized flowers of ericalean affinity are reported from the Turanian (ca. 90 MYBP, million years before present) of New Jersey. The fossils are remarkably well preserved and three-dimensional, and are the oldest known floral remains of Ericales. The series of fossil flower buds, floral fragments, and fruits are not identical to any modern genus of Ericales. The inverted U-shaped anthers with pseudoterminal awns, and the fluted syncarpous ovary of the fossils suggest affinities with basal Ericaceae, probably near extant Enkianthus, a taxon that also shares monadinous pollen with the fossil. Pollen grains were observed clumped on a stigma in one of the fossil flowers. Fossilized acid-resistant strands having characteristics, including similar diameter and sculpture pattern, in common with the muri connect pollen grains and, with scanning electron microscopy, appear continuous with the tectum, supporting the interpretation that they are viscin threads. These are the oldest reported fossilized viscin threads, and the only fossilized viscin threads found in situ in flowers. In modern Ericales and Onagraceae, the presence of viscin threads is associated with highly specific plant-pollinator relationships, raising the possibility that such specific pollinator-plant relationships had developed by the mid-Cretaceous. This is consistent with floral characters in these ericalean fossils, the presence of advanced meliponine bees in slightly younger sediments from the same region, and with the morphology and affinities of other fossil flowers from the same sediments.     

The Flora of Siahrud e Rudbar Protected Area,Northern Iran

The vascular flora of the Siahrud e Rudbar protected area was investigated in the years 2007 and 2008. It is a sylvatic area in the Guilan province with a total area of approximately 28289 hectares. A total of 711 plant specimens were collected and 616 species, subspecies, and varieties, belonging to 373 genera and 101 families were identified. Of these, 14 species (23%) are endemic to Iran. The documented flora exhibited many typically Hyrcanian species, including Hyrcanian endemics. The global phytogeographical affinities of the species were as follows: Euro Siberian 212%, Iran Turanian & Euro Siberian 168%, Pluriregional 117%, Iran Turanian 106%, and Cosmopolite 55%.     

Acacia (Mimosoideae): composition and affinities of the series Pulchellae Bentham

The composition and affinities of the bipinnate Acacia series Pulchellae Bentham are examined in the light of evidence from studies of gross morphology, seedling morphology, pollen morphology and seed chemistry. Acacia mitchellii , the only non-Western Australian species, is atypical and should be relocated in section Vninervea Vassal. The remaining 27 species (the Pulchellae sensu lato ) comprise a coherent group of 21 species (the Pulchellae sensu stricto ) and six less closely related ones. These 27 species appear unrelated to series Botrycephalae Bentham. Some affinities exist with phyllodinous groups, especially series Uninerves and Continuae .     

POLLEN MORPHOLOGY AND ULTRASTRUCTURE OF KRAMERIA (KRAMERIACEAE): UTILITY IN QUESTIONS OF INTRAFAMILIAL AND INTERFAMILIAL CLASSIFICATION

The genus Krameria is currently recognized as an enigmatic, monotypic family of dicotyledons. Previous studies of morphology, anatomy, and cytology have been unable to establish unequivocably its phyletic affinities. We report here the results of an intensive investigation of the pollen of Krameria using light, scanning electron (SEM), and transmission electron microscopy (TEM). Pollen characteristics of the genus were compared to those of all families referred to the Polygalales and to selected species of the Leguminosae-Caesalpinoideae, both groups with which Krameria has historically been allied. Superficially, the pollen of Krameria resembles that of the legumes more than that of genera in the Polygalales. However, in ultrastructure, it differs from the pollen of all taxa investigated from both groups. Within Krameria, several variations of a basic type of 3-colporate pollen are discernible. Species with similar pollen variants appear, on the basis of other morphological data, to represent natural groups within the genus. Nevertheless, an arrangement of groups of species of Krameria from “least” to “most” specialized, based on a logical sequence of modification of the pollen morphology, does not agree with any sequence of specialization using other morphological or ecological characters. It is concluded that pollen morphology and ultrastructure has systematic value for intrafamilial groupings of the Krameriaceae but that palynological modifications are incongruous with trends of specializations of other characters and, like many other lines of investigation, pollen studies do not provide significant data as to the phylogenetic affinities of the family.     

Pollen morphology and phylogenetic analysis of Eperua Aublet (Detarieae: Caesalpinioideae: Leguminosae)

The diverse pollen morphology of fourteen species of the genus Eperua is described and illustrated using light, scanning electron and transmission electron microscopy. Six pollen types are described and a key for their identification is provided. A cladistic analysis was carried out using macromorphological and palynological characters to form a hypothesis of relationships between taxa. The pollen morphology is discussed with regard to systematic relationships, function and phylogenetic significance of certain pollen morphological structures within the genus.     

Phytogeography of Genu and Homag,two mountains with an Irano–Turanian flora in the Saharo–Sindian regional zone,south Iran

The Saharo–Sindian regional zone encompasses the flat and arid areas of North Africa, the Arabian Peninsula, southern Iran and the deserts of Pakistan and west India. There are some scattered mountains situated within this area, like Hoggar in Sahara, Saint Catherine in Sinai and Genu and Homag in southern Iran. These highlands serve as interglacial refugia for cold adapted plant species. In the present study, phytogeographical patterns and relationships of the flora of Genu and Homag mountains are described and discussed in relation to the phytogeography of the flora of low‐lying Hormoz Island. According to a chorological assesment of the flora, Genu and Homag mountains belong to the Irano–Turanian region with 59% of the species restricted to this area. In contrast, the surrounding lowland plains are part of the Saharo–Sindian area with a rather high proportion of widespread species (17%) and Somalia–Masai‐linking elements (20%). It is noteworthy that several Turanian enclaves also occur in the lowland zone. Furthermore, the distributional patterns imply that the mountainous Irano–Turkestanian region is an integrated area which is supposedly distinct from the Turanian lowland areas in the north and from the Saharo–Sindian lowland areas in the south. On the other hand, the expansive floras of Turanian and Saharo–Sindian regions are linked to each other. Endemic species in lowland areas in south Iran are mostly either frost sensitive vicariants of cold adapted Turanian species or of Saharo–Sindian origin, while the highland endemics in the area trace their origins to the Irano–Turkestanian region.     

Studies on the Pollen Morphology of Trapa from Zhejiang

In the present work, pollen grains of 9 species of Trapa L. from Zhejiang were examined under LM and SEM. They are subsphaeroidal or subprolate, obtuse-triangular in polar view, elliptic or subrounded in equatorial view, and 3-colpate. In the equatorial area, there are three ridge-shaped appendages which elongates along apertures toward two poles and ultimately combined, the ornamentation of other part of exine is minute-verrucate. The genus Trapa is uniform in shape of pollen grains, type and position of apertures and ornamentation of exine, while differentiation can be found in size of pollen grains and shape of ridge-shaped appendage. All of these provide valuable evidence for the classification of Trapa and the verification of their affinities. The validity of Trapaceae, the evolutionarytrends of pollen morphology and the affinities of some species are discussed in this paper.     

Pollen morphology of Phyllosma and Sheilanthera (Diosminae: Rutaceae) and its taxonomic implications

Phyllosma (two species) and Sheilanthera (one species) are members of the taxonomically problematic subtribe Diosminae, Rutaceae. Pollen morphology of all three species was investigated by LM, SEM and TEM to shed light on their relationships to other genera of the subtribe. Sheilanthera shares pollen morphological features with many other species in the subtribe, but the pollen of Phyllosma is distinctive. Possible relationships between Sheilanthera and Acmadenia, and between Phyllosma and Agathosma are suggested. The macromorphological characters of the species correspond to the pollen morphology.     

Pollen morphology in relation to floral types and pollination syndromes in Pedicularis (Orobanchaceae)

Floral diversification in the genus Pedicularis (Orobanchaceae) is remarkable among flowering plants. In this genus, floral morphology and pollinator behavior are closely co-adaptive. In the current paper, pollen grains of 23 representative species of Pedicularis mainly from North America, with two species from Japan and two species from China, whose pollination ecology was previously studied, were examined using light microscopy and scanning electron microscopy. Two pollen aperture types and three kinds of exine ornamentation were recognized among these species. In addition, pollen data from previous and the current studies of Pedicularis were integrated and analyzed, together with some pollination characters. There was a significant association between pollen aperture types and corolla types, as well as between pollination syndromes and corolla types. However, there was no association of exine ornamentations with corolla types. The relationships and evolution of this genus were discussed with regards to pollen morphology, corolla types and pollination syndromes.     

绣球属(Hydrangea L.)及近缘属花粉形态的研究

为深入研究绣球属植物花粉形态的分类学价值和系统学意义,厘清绣球属与近缘属之间的系统发育关系,该文利用扫描电子显微镜(SEM,scanning electron microscope)对国产绣球属及其近缘属41种绣球花科(Hydrangeaceae)植物的花粉形态以及表面纹饰进行了观察。结果表明:绣球属及其近缘属的花粉为三孔沟;形状多数为长圆体形或近球体形;赤道面观为椭圆形或圆形;极面观多为圆形,少数为三角形或圆三角形。花粉外壁纹饰可分为网状和孔穴状。网眼内的三级纹饰可分为光滑和具颗粒状突起。根据花粉形状和外壁纹饰类型将上述物种划分为4个组,即花粉的形状为长圆体形,表面纹饰为孔穴纹饰;花粉的形状为长圆体形,表面纹饰为网状纹饰;花粉的形状为近球体形,表面纹饰为孔穴纹饰;花粉的形状为近球体形,表面纹饰为网状纹饰。以上可进一步细分为8个类型。上述表明花粉形态证据可为绣球属及其近缘属的属下分类和种间界定提供重要佐证;但结合前人的系统发育重建分析该属植物花粉形态的系统学意义相对有限,如花粉形态证据对于该属及其近缘种属系统发育树上大支的界定难以提供有力的证据。     

The diversity of interspecific pollen-pistil incongruity in Nicotiana

Nicotiana tabacum was used as a pistillate parent and crossed with three self-compatible species, N. rustica, N. repanda and N. trigonophylla, which were previously reported to have pollen tubes unilaterally inhibited by N. tabacum pistil. Temporal and morphological observations revealed distinct differences of pollen tube behavior among these incongruous crosses. Pollen tubes of N. repanda were arrested in stigma and those of N. rustica in the middle of the style. On the other hand, pollen tubes of N. trigonophylla continued growing at a slow rate. Tubes of N. repanda and N. rustica showed morphological abnormalities such as swelling, thick wall, and irregular callose deposition. In addition, tubes of N. rustica often elongated in reverse direction and wound about in the middle of the style. Although the tubes of N. trigonophylla were apparently normal in morphology, they were distributed throughout the transmitting tissue, differing from the self-pollination of N. tabacum in which they were confined to the peripheral region of it. The diversity of pollen tube behavior indicates that physiological causes of incongruity are different among the three crosses. Bud pollination enabled pollen tubes to reach the ovary in all crosses, indicating that the N. tabacum pistil acquired its ability to inhibit foreign pollen tube elongation with its development. When interspecific hybrids between N. tabacum and the other three species were pollinated by parental species, tubes reached the ovary in all crosses, but the elongation rate of tubes slowed down and morphology was abnormal.     

Pollen Morphology of the Genus Nomocharis and Its Delimitation with Lilium

In this work examined were pollen grains of 6 species of Nomocharis and 4 species of Lilium, all under LM and SEM, but Nomocharis saluenensis Balf. f. under TEM. The pollen grains are monocolpate (distal) in Nomocharis, monocolpate or 2-3-porate in the species of Lilium examined. Two types of pollen grains in Nomocharis are recognized based upon the exine stratification and sculpture. The pollen characters and gross morphology, and their evolutionary trends in both Nomocharis and Lilium are discussed. Our conclusions are as follows: 1. Lilium henrici Franch. 、L. souliei (Franch.) Sealy 、L. lophophorum (Bur. et Franch.) Franch. and L. nanum Klotz. et Garcke differ from Nomocharis in the aperture and sculpturing elements. Their pollen morphology supports their being placed in Lilium. 2. The pollen grains of both Lilium lophophorum (Bur. et Franch.) Franch. and L. nanum aggregate are monocolpate or 2-3-porate, which shows an evolutionary trend of aperture from monocolpate to porate, as suggested by Walker and others [Walker et al., (1975), and Chanda (1979)]. 3. In Balfour’s (1918) classification system of Nomocharis, N. pardanthina Franch. and N. meleagrina Franch. belong to Sect. Nomocharis, while N. forrestii and N. biluoensis are placed in Sect. Ecristata, but their pollen grains are all reticulate. They refer to type I (see Table 2). Thus, it does not seem reasonable placing in a single section, Sect. Ecristata, N. forrestii and N. biluoensis with the reticulate exine and N. saluenensis and N. aperta with the two-row-ritipilate exine. 4. Nomocharis saluenensis Balf. f. differs from Lilium in the exine sculpture, which seems to support placing it in Nomocharis. 5. Muri of N. forrestii Balf f. and N. biluoensis s.y. Liang show a tendency of connecting each other by heads of pili, and these two species are intergraded with the other species of the type I with respect to gross morphorlogical characters. It is thus considered that the reticulate pollen grains in Nomocharis is derived from ritipilate ones. This opinion is also held by Nair (1965). 6. Nomocharis differs from Lilium in the exine ornamentation, but some species of Nomocharis are very similar to Lilium in the gross morphology. It shows the close affinity between Nomocharis and Lilium.     

Pollen grain morphology of Nolana L. (Solanaceae: Nolanoideae: Nolaneae) and related genera of southern South American Solanaceae

Nolana comprises 89 species almost entirely restricted to the Atacama and Peruvian deserts. These species are adapted to the arid lomas environment of northern Chile and southern Peru, where they depend on marine fog locally known as garúa or camanchaca for their development. Recent molecular phylogenetic studies provide support for the placement of Nolana in the Solanaceae rather than Nolanaceae. Additionally, a sister relationship with the tribe Lycieae has been suggested. The pollen morphology of 111 species from 18 genera of southern South American Solanaceae was investigated under light and scanning electron microscopes in order to establish the palynological affinities of Nolana within the Solanaceae and to investigate if pollen morphology is congruent with the phylogenetic relationships and former taxonomic classification of the species of Nolana. The following genera were studied: Nolana, Cestrum, Combera, Dunalia, Fabiana, Jaborosa, Latua, Lycium (incl. Grabowskia, Phrodus), Nicandra, Nicotiana, Nierenbergia, Petunia, Physalis, Reyesia, Salpiglossis, Schizanthus, Solanum and Vestia. Two pollen types that differ in exine structure were distinguished within Nolana; these pollen types are congruent with recent phylogenetic studies, thus, we propose to reinstate Nolana sect. Sorema.     

Pollen Morphology of Neottianthe (Orchidaceae) and Its Taxonomic Significance

The genus Neottianthe (Orchidaceae) consists of about 12 species in the world, of which all are found in China and nine are endemic to China. The pollen morphology of this genus is very specific in shape and composition. All pollen grains in Neottianthe are of a compound pollen grain, called massula, in which of many monad pollen grains adhere togeth er. A massula is usually long and narrow trigonous cone in shape. Pollen grains can be divid ed into five types according to ornamentation, of exine surface: (A) pollen surface almost smooth, or very obscurely fossete, (B)perforate, (C) fossulate or foveolate, (D) reticuloid, and (E)typically reticulate. Neottianthe. calcicola, N. monophylla, N.pseudo-diphylax and N. cucullata have been merged into one species, N. cucullata, by some taxonomists. This treatment is not supported by the pollen morphological data, because pollen morphological characteristics of above-mentioned four species are different from each other. Therefore, pollen morphology shows that they are all independent at the specific level. Finally, it must be stressed that N. camptoceras is uniquite in the genus Neottianthe for its pollen shape,size and surface ornamentation of pollen exine.     

FOSSIL FLORAL EVIDENCE OF MALPIGHIACEAE AND AN EARLY PLANT-POLLINATOR RELATIONSHIP

Fossil flowers with affinities to Malpighiaceae have been discovered in the Middle Eocene Claiborne formation of northwestern Tennessee. The new taxon Eoglandulosa warmanensis gen. et sp. nov. Taylor and Crepet, has paired glands on the five sepals, clawed petals and tricolporate pollen with reticulate ornamentation and an unusual infratectal wall structure of anastomosing elements. The fossil is similar in wall structure to some extant species of Malpighiaceae. Glandular floral morphology in extant species is associated with specific anthophorid bee pollinators and the fossil evidence suggests that such specific plant-pollinator relationships existed during the Eocene. This fossil species also suggests that by the Eocene, South American floral elements had migrated to North America via island pathways, and that the Mississippi embayment was nearly frost-free.     

Pollen morphology of the genus Nothofagus and its taxonomic significance

The present paper describes the pollen morphology of 26 species and 2 varieties in Nothofagus from Australia, New Zealand, New Caledonia, New Guinea and South America. Pollen grains were all examined with light microscope (LM), scanning electron microscope ( SEM ) and transmission electron microscope(TEM). A comparative analysis of pollen exine ultrastructure was made for some species. The results are summarised as follows: Pollen grains are oblate to peroblate, 5～8-short-colpate, rarely 4- or 9-colpate; colpi generally thickened at margins; pollen surface spinulose. The exine ultrastructure of Nothofagus differs considerably from that of the other genera in the Fagaceae. The pollen grains of the species examined here show great differences in shape, size, colpal number and characteristics of colpi at margins and could be divided into three distinct types, i.e. N. brassii type; N. menziesii type and N. fusca type.     

Morphology of pollen and orbicules in some Dioscorea species and its systematic implications

Pollen and orbicule morphology of 35 Dioscorea L. species is described based on observations with light microscopy, and scanning and transmission electron microscopy. Pollen and orbicule characters are critically evaluated and discussed in the context of existing hypotheses of systematic relationships within the genus. Pollen is mostly bisulcate (sometimes monosulcate) with a perforate, microreticulate or striate sexine. Our results indicate that pollen data may be significant at sectional rank. The close relationship between sections Asterotricha and Enantiophyllum proposed by Burkill and Ayensu is supported by pollen morphology as all species investigated share bisulcate, perforate pollen with small perforations and a high perforation density. Macromorphological differences between the two compound-leaved sections Botryosicyos and Lasiophyton are also supported by pollen morphology; pollens of these two sections have very different perforation patterns. Orbicules in Dioscorea are mostly spherical and possess a smooth or spinulose surface. The latter is often correlated with a striate sexine.     

中国兜被兰属植物的花粉形态及其分类意义

兜被兰属Neottianthe全世界共约12种,中国均有分布,其中9种为我国所特有。本属花粉形态 和组成都很特殊,它是由许多单粒花粉粘结在一起形成复合花粉——花粉小块,其形状一般为狭长的三 棱锥体形。外壁表面具5种纹饰类型:(A)近光滑,或具十分微弱的小凹陷;(B)外壁具穿孔状纹饰; (c)外壁具沟渠状纹饰;(D)外壁具拟网状纹饰;(E)具典型的网状纹饰。奉属有些种类,例如:N．cal- cicola,N．monophylla,N．pseudo-diphylax和N．cucullata等4种在分类上还存在许多问题,有些分类 学家把N.calcicola,N.monophylla,N.pseudo-diphylax 3种均归并于N．cucullata。孢粉学资料表 明上述4个种花粉特征完全不同,因此,上述4种仍应各自独立为种。最后,强调指出N．camptoceras的花粉形状和外壁纹饰等特征在本属为特殊类型。