12th Flora of Thailand Meeting

 

Papers abstract

 

The Southeast Asian Botanical Collections Information Network (SEABCIN)

Peter C. van Welzen

 

A few years ago, Paul Kessler came up with the idea to form a joint database between the Leiden Herbarium in the Netherlands and a few Southeast Asian herbaria. The European Community (EC) had a special programme for IT/C development in SE Asia and we were just in time to jump the bandwagon as the call for the last round was ringing. Luckily, the EC was mightily, impressed by our proposal and we received the green light for our project. The BKF (The Forest Herbarium, Royal Forest Department) herbarium, KEP, SAN, SAR (Malaysia), BO (Indonesia), PNH (Philippines), and L (Netherlands) will create a joint specimen database, for which FOH (Oxford, UK) will provide the software. SING (Singapore), WAN (Wanariset, Indonesia), K (Kew, UK), TCD (Dublin, Ireland) will also co-operate in the project. The main goal of the project is to equalise our different databases through software into a joint general database. For this we needed two sets of very strict rules: - Standard data formats (e.g., the definition of the fields in the database) - Standard data entry formats (e.g., the way in which the data are digitised). These rules were discussed during a workshop in March in Saraburi. The project comprises several phases: - equalising existing data: Every herbarium will improve the data of all participants that pertain to their country. - data entry of the Dipterocarpaceae as a try-out. - development of software tools for updates of identifications, equalising data, identification lists, distribution maps, etc. - final workshop and training sessions. One other purpose, besides facilitating the needs of the co-operating herbaria (and more are welcome to join), is to publish the data on the internet. This is very important for, for instance, scientists, which co-operate in the Flora of Thailand project. However, due to local policies parts of the database may be shielded (e.g., collecting localities, CITES-list species).


 

Plant collectors, collecting rates and distribution patterns in Thailand and their impact

J.A.N. Parnell1, D.A. Simpson, D.W. Kirkup, P. Chantaranothai, P.C. Boyce. P. Bygrave, S. Dransfield, M.H.P Jebb, J. Macklin, C. Meade, D.J. Middleton, C.A. Pendry, A. Prajaksood, S. Suddee & P. Wilkin

 

Analyses of collection and distributional data taken from specimens used for revisions of various plant families for the Flora of Thailand series are presented. The data are largely for families revised by staff or students formerly or currently resident in TCD. They include the Annonaceae, Apocynaceae, Araceae, Araliaceae, Cyperaceae, Dioscoreaceae, Eriocaulaceae, Gramineae (Bambusoideae), Labiatae (sensu auctores veterum), Myrtaceae, Orobanchaceae, Plantaginaceae, Polygalaceae and Santalaceae. The data total ca.7,000 records, including all available collections for most of the above families and are likely to be representative of flowering plant distributional patterns in Thailand as a whole. Estimates are made of rates of collection (the number of collections of plant material per unit area per unit time) and, using Index Herbariorum, of the total number of Thai collections held in the world’s herbaria. The analyses show that the collecting rate for Thailand is low in comparison to many surrounding countries; that the collecting density for Thailand is an order or two orders of magnitude lower than that for two sample European countries (Ireland and the U.K.); that 25 % of all records derive from a single Province (Chiang Mai) which has three times the number of records as the next most collected Province; that the top three most collected provinces hold 33% of all records; that some provinces are ? bereft of any representatives of the above families; that mountainous areas are likely to appear to be hot spots of diversity simply because they have been repeatedly, and intensively, sampled; that the majority of species in many families are known from very few collections and that 10% of the species in these families form 45% of the collected material. Further resolution of the data to half degree squares reveals that the data are very tightly localised within each province. Many plant distribution patterns in Thailand (and hence elsewhere in S.E. Asia) are likely to be artificial, arising from the paucity of data; however some patterns are, because of habitat or other specificity, likely to be accurate. Further targeted collecting is essential if structured prioritisation for conservation management is to be undertaken. Few collectors are responsible for the vast majority of the collections made in the country; more need to be involved.


 

Diversity and distribution patterns of the Asiatic Ardisia

Hu Qi Ming

 

An analysis was made on the species number of the genus Ardisia Sw. in each of the 14 flora regions in Asia, namely: China, Indochina, Myanmar, India, Thailand, Malay Peninsula, Sumatra, Borneo, Java, Philippines, Sulawesi, Moluccas, Lesser Sunda Islands and New Guinea. A total 441 species were recorded from published and reliable unpublished floras and checklist; of these, 348 species are restricted in their distribution, being endemic to one of the above regions; only 93 species are distributed in more than two regions. The highest percentage endemism occurs in New Guinea (84.4%), followed by the Philippines (79.6%), Borneo (68.2%) and Sulawesi (66.6%), India (63.3%), Indochina (63%), Sumatra (52.5), Moluccas (50%), China (46.2%), Malay Peninsula (45.7%), Thailand (43.7%), Myanmar (37%), while the islands of Java and the Lesser Sunda Islands have the lowest levels of endemism, being 13% and 36.4% respectively. Statistics of the distribution of the subgenera in and the index of similarities among these regions are also provided.


 

Preparing the Orchidaceae for Flora of Thailand: starting point, plans, and prospects

Henrik ?renlund Pedersen

 

The Orchidaceae are the largest plant family in Thailand, but so far only the small group of Apostasioids has been included in Flora of Thailand, as it was treated as a separate family by Larsen and de Vogel in 1972. Recently, however, a plan has been prepared to include the remaining part of the Thai orchids (c. 1200 species) in a volume composed of six instalments. The first instalment will provide an entrance key to the family and deal with the genera of Cypripedioideae, Vanilloideae, and Orchidoideae. The five others will each cover one or more larger groups of Epidendroideae. Partly due to CITES-related problems in exchanging plant material, partly due to the recurrent need for new, supplementary collections, it is considered important that each instalment is written by at least one Thai and one European author. The conditions for carrying through this project are extraordinarily good at present. First, mainly the works of Seidenfaden from the second half of the 1900s have provided an excellent taxonomic basis at the species level. Second, the Botanical Museum in Copenhagen has started to register all Seidenfaden’s important collections, illustrations, and notes in a database – and, depending on the necessary copyright agreements, will make these data accessible on the internet; additionally, it seems likely that Seidenfaden’ s illustrations can be made available for publication in Flora of Thailand. Third, the international Genera Orchidacearum project is currently providing a thoroughly revised set of generic circumscriptions that can be utilized for securing a homogenous treatment on the genus level. Fourth, the research project The Orchids of Thailand, their Taxonomy and Conservation Biology, I (scheduled for five years, but intended to be followed by II, III, etc.) was initiated in 2002 as a joint venture between the Forest Herbarium, Bangkok and the botanical Museum, Copenhagen; the primary goal of this project is to procure additional data and collections for the orchid account in Flora of Thailand.


 

The Seidenfaden Orchid Database, a new tool for research and conservation

Katja Anker

 

From 1956 to 1982 the late Dr Gunnar Seidenfaden, former Danish ambassador in Thailand, arranged more than 20 expeditions in Thailand in collaboration with the Royal Forest Department. Large numbers of live orchids were collected, and flowers were photographed and preserved in spirit when the plants subsequently flowered in Bangkok or in the Botanical Garden in Copenhagen. A large share of the spirit material was carefully sketched by Seidenfaden himself and later inked-in by various professional draftsmen before publication in his long series of orchid books. When Seidenfaden passed away on the 9th of February 2001, he left all his botanical collections and his orchid library to the Botanical Museum and Library, University of Copenhagen, together with a generous amount of money for the reorganization and future utilization of the material. During the autumn 2001, all Seidenfaden's collections (viz. spirit samples, colour slides, analytical sketches, and ink drawings) were sorted and deposited at the Botanical Museum, and in early 2002 a database was constructed for subsequent registration of this material. The digitizing of Seidenfaden’s collections is now steadily progressing. It will be possible to search the Seidenfaden Orchid Database for, e.g., the taxonomic identity of material (of all the above categories) known by collection number, or to generate lists of material available for particular species and/or from particular localities. Additionally, it is our intention to scan all the different types of illustrations to make them viewable when searching the database. Apart from being a very useful tool for the routine administration of Seidenfaden's collections in Copenhagen, the Seidenfaden Orchid Database has a large potential as information source in connection with the preparation of the orchid account for Flora of Thailand (to be coordinated from Copenhagen) as well as for other scientific research and conservation projects, particularly in Thailand. Thus, the database will also play an important role in connection with scientific repatriation. For optimizing the utilization of the Seidenfaden Orchid Database abroad, the base will be made accessible on the internet, through the homepage of the Botanical Museum and Library. Illustrations will be viewable on the internet to the extent permitted by the copyright agreements we achieve.


 

Hala-Bala: The Tropical Rain Forest of Southern Thailand

Chawalit Niyomdham

 

Hala-Bala is a Malayan-type forest located in Yala and Narathiwat provinces at the southernmost tip of Thailand. It lies approximately between 5? 37? to 6? 14? north and 101? 8? to 101? 51? east, covering an area of approximately 1,338 square kilometers. The area is adjacent to Malaysia’s Belum Forest and its elevation ranges from the lowest point of about 50 meters to the highest spot of 1,500 meters above mean sea level. The climate supports tropical rain forest with a mean annual temperature of 27.6? C, an annual average rainfall of 2,560 mm in 171 rainy days and no dry month. November and December are the wettest months, February to April the driest. The area’s relative humidity ranges from 77% to 80%.

 

From a phytosociological viewpoint, the area’s vegetation can be classified into 3 main types of which 7 major plant communities are recognized:

 

1) Tropical Lowland Rain Forest in which:

A. Lowland Dipterocarps and Palms occupy the area under 600 m altitude,

B. The higher terrain between 600-1,000 m altitude with scattered communities of

b1) Shorea and Eugeissona,

b2) Shorea and Johannesteijsmannia,

b3) Shorea and Calamus castaneus

 

2) Lower Montane Rain Forest in which

A. Fagaceae and Illicium in areas between 1,000-1,400 m altitude,

B. Podocarpaceae-Ericaceae and Lauraceae are major plant communities over 1,400 m altitude

 

3). The vegetation on limestone hills between 600-1,000 m altitude which is mostly occupied by an Ericacious and Dacrydium community.


 

Thai Cyperaceae, Distribution and conservation

David A Simpson

 

The Flora of Thailand Cyperaceae account was published in 1998 and includes basic distribution data for each species. To improve taxon distribution patterns a simple GIS model at 30’ square resolution is being used to determine both areas and taxa which are still under-collected. Data are also being taken from herbarium material in Thailand and Europe. A comprehensive database of distributions is being assembled. An online atlas at 30’ square resolution will then be prepared, linked to specimen images and the Flora account. This will represent some of the first detailed distribution mapping for a whole plant family in any tropical country. A hardback copy of the Atlas is also planned. Using GIS, past and present distribution patterns in Thai Cyperaceae will be analysed and linked to factors such as habitat type and geology. These will help to determine the environmental well-being of habitats (particularly wetlands) through changes in the distribution and frequency status of species. The data will also be used to develop conservation ratings for Cyperaceae species in Thailand and will allow determination of priorities / provision of advice for both habitat and species conservation to be carried out more effectively and with greater accuracy.


 

Yams and their allies (Dioscoreales) and related Monocots in the Thai Flora

Paul Wilkin, Chirdsak Thapyai & Kongkanda Chayamarit

 

The paper will give a contemporary (APG2) view of monocot family limits. Examples will be presented from the Thai flora, and an overview given of progress in production of monocot family accounts. It will focus in more detail on the phylogenetic relationships of Dioscoreales and Dioscoreaceae, and conclude by looking at the diversity of Dioscorea L. in Thailand and exploring the origins of that diversity.


 

Survival strategies and means of dispersal in Thai Cucurbitaceae

Willem J.J.O. de Wilde

 

Cucurbitaceae are an old, isolated, pantropical family. Even in the restricted area of Thailand the c. 50 species in 20 genera display a wide variety in fruit types and in seed dispersal: by wind, gravity, birds, rodents and ants. The dry season is survived either by means of substerraneous rootstocks or tubers or by dormant seeds.


 

The geographical position of Thai Cucurbitaceae in Asia

Brigitta E.E. Duyfjes

 

Apart from cultivated genera, the indigenous Cucurbitaceous flora of Thailand comprises some 20 genera (about 50 species), which means that Thailand scores quit high for the region. In Cucurbitaceae are, comparatively, many monotypic genera or genera with only a few species. Several genera have a restricted distribution, others are widely distributed. Centres of development of Cucurbitaceae in Asia are (S) China and Malesia (New Guinea). By means of distribution maps will be shown that Thailand is a hotspot for the family, with various endemic species, in genera with mainly either northern, or southern, or just Thailand-centred distribution.


 

Sauropus (Euphorbiaceae): Species and Patterns in Thailand

Peter C. van Welzen

 

Sauropus is one of the notoriously difficult genera in subfamily Phyllanthoideae, mainly small-leaved plants with axillary fascicles of flowers. It ranges from Mauritius throughout tropical SE Asia up to Australia and New Guinea. Sauropus has two centres of speciation, one is in SE Asia with an emphasis on Thailand, and the other is in Australia. In total about 50 species are known, most of them are highly endemic, a few are very widespread. Typical for Sauropus are the flat staminate flowers (with a 6-lobed calyx, calyx scales and an androphore with apically three horizontal filaments with the anthers abaxially) and the gynoecium with usually three horizontal, split and crescent-moon-like stigmas. Most of the 24 Thai species are restricted to Thailand or just pass the border into Myanmar or Malaysia. A few species are widespread, two of them, S. androgynus (L.) Merr. (a vegetable) and S. rhamnoides Blume, look quite alike and are very variable. S. rhamnoides ranges from India to the Philippines and the Lesser Sunda Islands. For Thailand it was tentatively identified by Airy Shaw (Kew Bull. 32, 1977, 81), but appeared to be confused with S. garrettii Craib. S. garrettii (Chiang Mai up to China) was thought to be disjunct in Thailand, present in the North and in the Southeast; the southeastern specimens are S. rhamnoides. The differences between these species will be explained. The majority of the Thai species is found in the North and west of Thailand. Often related species range from Chiang Mai up to Kanchanaburi. A few species have very local distributions, these are often very small woody herbs with cauliflorous long inflorescences. One group within Sauropus, the Hemisauropus group comprises among others three small leaved species. Two are present in the central part of Thailand, from Loei to Bangkok, and disjunct east and west of it is S. kerrii Airy Shaw. The same disjunct distribution is shown by S. asteranthos Airy Shaw. One taxonomical problem is posed by the variable Sauropus quadrangularis (Willd.) M?ll.Arg. Three varieties (former species) were recognised, but these all merge together in Thailand and all varieties had to be lumped.


 

Annonaceae of Thailand

Paul J.A. Kessler

 

The Annonaceae is a large pan-tropical plant family with quite a lot of representatives within the Flora of Thailand area. With recent developments in databasing the herbaria at BK, BKF and L were able to enter label data of Annonaceae into a database. Current analysis of the BRAHMS (Botanical Research and Herbarium Management System) at Leiden revealed that c. 35 genera with c. 120 species occur in Thailand, mainly in the lowland tropical rainforest. The National Herbarium of the Netherlands houses about 17,000 specimens of Annonaceae; c. 850 specimens are recorded from Thailand. These represent usually recent collections made after 1950 (more than 90 %). Historical collections include duplicate material of Kerr, Put, and Kostermans. Quite a number of species are shared with the Flora Malesiana region, especially those found in South Thailand where the Annonaceous diversity resembles that the Malay Peninsula. The number of genera is almost the same, but the number of species is considerably higher (38 genera and c. 203 species according to Sinclair, 1955). The Flora of Vietnam (Ban 2000) records 29 genera and 157 species, a number which is probably even too high, Starting this year an international group of scientists has committed themselves to revise the Annonaceae for the Flora of Thailand. As most of the genera are not very large thus comprising less than 10 species each, the study of certain taxa is even suited for relatively inexperienced students. According to the schedule it will be possible to finish this important family within the next three years. 


 

Biogeography of Thai Dipterocarpaceae

Rachun Pooma

 

Sixty-three taxa of Dipterocarpaceae in eight genera have been recorded in Thailand. A cladogram based on morphological characters of Dipterocarpaceae found in this country is used for an historical biogeography analysis. The areas of distribution in Thailand are demarcated into 10 areas, based on present-day distribution. The results of the area cladogram show overall similarity patterns between present-day distributions rather than historical relationships between the areas (biotas). The relationships between areas are seemingly logical as the cladogram shows a continuous biogeographical area. A few really vicariant distributions were found. Further work is therefore needed to find the correct historical relationships between areas (general patterns) by adding non-related taxa. A new taxonomic cladogram using molecular data will be needed. Based on the actual and potential distribution of Thai Dipterocarpaceae, patterns can be grouped into species with widespread, disjunct or restricted distributions. These results were obtained thanks to a much larger number of collections compared to past studies; indeed, a considerable number of recent collections were used. Conservation statuses are based on the IUCN Red List Categories and Criteria. Thirty-three species were considered Critically Endangered (CR), three of them believed to have disappeared from Thailand (Shorea laevis, S. macroptera, S. sumatrana). Fourteen species were evaluated as Endangered (EN), and 10 species as Vulnerable (VU). Five widespread deciduous species fall within the category Lower Risk (LR), while one species, Hopea siamensis is not well enough known to be evaluated, it is then Data Deficient (DD).


 

Molecular Phylogeny and Taxonomic Reconsideration of the Genus Peliosanthes (Convallariaceae)

Jun Yamashita, Art Vogel & Minoru N. Tamura

 

J. D. Hooker recognized nine species of Peliosanthes in the Flora of British India (1892). H. N. Ridley recognized nine species in the Flora of the Malay Peninsula (1924). However, J. P. Jessop (1976) regarded all the previously recognized species of Peliosanthes as the same species, P. teta. After the treatment of Jessop, Peliosanthes is often considered as monotypic. In this study, we analyze DNA sequence of the chloroplast trnK and rbcL genes of Peliosanthes from Thailand as well as Malaysia, Indonesia and Taiwan in order to construct a molecular phylogeny of Peliosanthes and to reconsider whether Peliosanthes is really monotypic or not. According to the strict consensus of the 16 equally most parsimonious trees, two major clades are formed in Peliosanthes: a clade (1) of P. teta, P. stellaris, P. cf. monticola, P. viridis, P. campanulata, P. albida and P. violacea with less than 50% bootstrap support and a clade (2) of P. gracilipes, P. sinica, P. arisanensis and P. cf. macrostegia with 54% bootstrap support. With in the clade (1), two subclades are formed: a clade (1-1) of. P. teta, P. stellaris, P. cf. monticola, P. viridis and P. campanulata with 88% bootstrap support and a clade (1-2) of P. albida and P. violacea with 97% bootstrap support. Within the clade (2), two subclades are formed: a clade (2-1) of P. gracilipes and P. sinica with less than 50% bootstrap support and a clade (2-2) of P. arisanensis and P. cf. macrostegia with 95% bootstrap support. Seven individuals of Peliosanthes albida from Malaysia and Indonesia form a clade with 100% bootstrap support. Six individuals of P. campanulata from Thailand and Malaysia form a clade with 95% bootstrap support. Three individuals of P. violacea from Malaysia form a clade with 87 % bootstrap support. Two individuals of P. cf. monticola from Malaysia and Indonesia form a clade with 70% bootstrap support. Two individuals of P. gracilipes from Thailand have the identical DNA Sequence of the trnK and rbcL genes. Thus, the narrower species concept of Peliosanthes is not necessarily rejected, although further studies are needed in order to know whether they are biological species or not. Two individuals of P. teta and two individuals of P. stellaris do not form a clade, respectively, but the four individuals form a clade with 99% bootstrap support. It should be reexamined whether P. stellaris really differs from P. teta or not.


 

The character states of Thai Rubiaceae

Christian Puff

 

With around 100 genera and an estimated 500 species, the Rubiaceae is one of the largest families in the Flora of Thailand. Although normally easily recognized by a distinct set of characters (opposite leaves with stipules, inferior ovary, etc.), many character states of the Rubiaceae exhibit a very wide range of variation. Some of these (growth forms and architecture; leaf characters such as aniso- and heterophylly, types of domatia and of bacterial nodules, and collecters on stipules; inflorescence types and their derivation; basic flower and fruit types and their modifications; secondary pollen presentation, protandry, heterostyly and dioecy) will be discussed. Selected easy to see, yet often overlooked field characters will be pointed out. A preliminary multi-access key to Thai Rubiaceae will also be presented.


 

Note on the Genus Argostemma Wall. (Rubiaceae) of Malay Peninsula and Peninsular Thailand

Kitichate Sridith

 

The status of some taxa of the genus Argostemma Wall. (Rubiaceae) in the Malay Peninsula and Peninsular Thailand are discussed based on studies of herbarium specimens from various herbaria (BKF, K, KEP, L, S and UM) together with the field surveys of the natural populations of the genus in the Malay peninsula and Peninsular Thailand.


 

Araceae in Thailand

Duangchai Sookchaloem

 

The Araceae family is normally abundant in tropical forest. It includes many species that are important as a source of food and medicine or are economically important, i.e. ornamentals. The species in this family should be thoroughly revised based on morphological observations of herbarium and living specimens. There are an estimated 150-170 species and 23 genera of Araceae in Thailand. The collected specimens are classified into generic and specific levels with 46 species of the genus Amorphophallus, 27 species of Typhonium, 10 species of Aglaonema and Homalomena, 8 species of Alocasia and Arisaema, 6 species of Rhaphidophora and Scindapsus, 4 species of Cryptocoryne, 3 species of Epipremnum, Pothos, Pseudodracontium and Schismatoglottis, 2 species of Anadendrum, Colocasia, Hapaline, Pycnospatha and Remusatia, 1 species of Amydrium, Lasia, Pistia, Piptospatha and Steudnera. Among these, 20 species of Amorphophallus, 14 species of Typhonium and 1 species of Aglaonema are new to science. Piptospatha is recognized as a new generic record for Thailand since the discovery of P. perakensis. To elucidate the status of Aglaonema, the genus was revised based on comparative morphology, palynology and enzyme electrophoresis. 10 species were recognized. Homalomena is one of the largest genera besides Amorphophallus and Typhonium and consists of a complex group of many species. Three species of Homalomena are closely related, viz. H. oculta, H. aromatica and H. cordata. This group is allied to the Indochinese species H. cochichinensis and H. tonkinensis. The pollen and leaf anatomical characters of some genera were also examined in the systematic study of this family.


 

Biogeographic studies of conifers: evidence from conifer fossils from the Tertiary of Northern Thailand

Paul J. Grote

 

The present occurrence and distribution of plants in Thailand are the result of many factors, including immigration and emigration of plants, extinction, and evolution of new species. Studies of conifer fossils from Tertiary deposits of Northern Thailand provide evidence on how the composition and diversity of these plants have changed over geologic time. At present, conifers in Thailand comprise 11 species in four families: 7 species in 4 genera of Podocarpaceae; 1 species of Calocedrus in Cupressaceae; 2 species of Pinus in Pinaceae; and 1 species of Cephalotaxus in Cephalotaxaceae. Fossils thought to be of Late Oligocene or Miocene age from lacustrine and swamp deposits from the Li Basin, Amphoe Li, Lamphun, comprise twigs, needles, seed cones, and seeds of Sequoia (Cupressaceae s.l., including Taxodiaceae), a genus found today only in temperate western North America. A twig and needles are also known for Sciadopitys (Sciadopityaceae), today only found in temperate Japan. Coalified and charcoalified wood from Li Basin and from Lampang Basin, Amphoe Mae Tha, Lampang (possibly Miocene age) appears to consist of a species of Podocarpaceae, two species of Cupressaceae s.l., and two additional species of uncertain affinity, but possibly Podocarpaceae or Cupressaceae. Although study of fossil conifers in Thailand is at a preliminary stage, there is some suggestion that the conifers presently occurring in Thailand represent a relict of a once larger diversity of conifers during the Oligocene and Miocene.


 

Systematic and Paleophytogeographical Study of Leguminous Fossil leaves from Li Basin, Northern Thailand, using Morphological and Venation Analysis

Prakart Sawangchote, Paul J. Grote, David L. Dilcher

 

In Thailand paleobotanical systematic studies of fossil leaves and other related fields such as paleophytogeography, paleovegetation and paleoclimate seem to have been ignored for quite a long time since the work of Endo (1964, 1966) at Li Basin. As part of the research community we initiated a project to study Cenozoic plants of Thailand with the hope that we could contribute our work towards an understanding of how plants have been evolving, along with their environments, through the geological past (including at the individual, population and community level). In recent field trips, fossil leaves were recovered from lacustrine sediments at Ban Pu and Ban Pakha subbasins, Li Basin, at Ampoe Li, Lamphun, thought to be of Upper Oligocene or Lower Miocene age. Many of these fossils were assigned to various taxa other than those reported by Endo (1964,1966), and the fossil assemblage may represent mixed forests of angiosperms and gymnosperms, dominated by Sequoia. Fossil leaves with affinities close to members of several leguminous genera such as Albizia, Archidendron, Cassia, Crudia, Derris, and Peltophorum were also found and are being studied systematically. Before these fossil morphotypes are assigned to taxonomic ranks, morphological and venation analyses (and cuticular analysis in cases when cuticle can be obtained from fossil leaves) on possible living counterparts will first be performed. The validity of using living leaf morphology for identification to generic or species level and paleophytogeography of these leguminous fossils will also be discussed.


 

Podostemaceae of Thailand

Masahiro Kato

 

Podostemaceae, with 3 subfamilies, 57 genera and c. 270 species, are aquatic angiosperms occurring on rocks in waterfalls and rapids in the tropics and subtropics of the world. Because of small plant sizes and extreme habitats, they have often been overlooked. Molecular phylogenetic data are useful to analyze the phylogeny and taxonomy of Podostemaceae. Current classifications of the family recognize 7 genera and 10 species in Thailand (2 gen. 2 spp. in Tristichoideae; 5 gen. 8 spp. in Podostemoideae). During the recent 4 years we have collected new taxa, resulting in totally 8 genera and 21 species. The number of species is equivalent to that (20 spp.) of South Asia (Sri Lanka and south India), indicating that Thailand is one of two centers of distribution of Podostemaceae in Asia. Cussetia, a new genus based on Dalzellia diversifolia (and C. carinata), is endemic to Southeast Asia. Although Dalzellia (exclusive of Cussetia) has been considered to occur only in South Asia, 2 new species occur in Thailand. The genus Malaccotristicha with M. malayana known so far from Malaya and peninsular Thailand, is now composed of 4 species, 3 in Thailand and Malaya and 1 in northern Australia (M. australis). Cladopus taiensis is an endemic to Thailand, while several other species are distributed in neighboring regions. In Thailand there occur nearly as many species (4 spp.) of Polypleurum as in South Asia (5 spp.). Eight species of Hydrobryum (in total ca. 11 spp.) occur in Thailand, a center of distribution, while the monotypic genera Hanseniella and Taidrobryum gen. nov. are endemic to Thailand.


 

Census of Woody Vines on the Mo Singto long Term Forest Plot, Khao Yai National Park, Thailand

Warren Y. Brockelman

 

All woody vines over 3 cm in diameter have been tagged and mapped in the Mo Singto long term forest research plot in Khao Yai National Park. This plot was established during 1996–2001 as an outgrowth of a long term research project on gibbons (Hylobates lar), in order to analyze diet and foraging behavior in detail. The plot, at 740–810 m in elevation and covering 30 ha in area, contains about 200 species of trees over 10 cm in dbh at a density of 547 trees ha?1. The woody vine census was completed in 2001 and revealed a total of 121 species in about 35 families, of which about 100 have been identified from voucher specimens with reproductive material. At least 20 species of vines provide young leaves or ripe fruits for consumption by gibbons The census enumerated both genets, stems emerging from the ground, and ramets, or stems ascending trees which are measured at breast height. The locations of the genets were recorded and the host tree of each ramet. The density of genets > 3 cm in diameter on the plot is 293 plants ha?1 and the density of ramets is 404 stems ha?1. The most speciose family is Apocynaceae (at least 12 species), and the most common species is Uncaria scandens (Sm.) Hutch. (Rubiaceae) with 19.3 genets ha?1. Color photographs of the stems of all species of climbers have been taken, and a guide to the identification of climbers on the plot is being prepared based on stem characters including color of outer wood and sap.


 

A Taxonomic Revision of tribe Ocimeae Dumort (Labiatae) in continental South East Asia

Somran Suddee

 

The tribe Ocimeae is fully revised for Burma, Thailand, Laos, Cambodia and Vietnam. Seventy-seven taxa including 70 species and 14 varieties are recognised under 9 genera including Hyptis Jacq., Siphocranion Kudo, Isodon (Schrad. ex Benth.) Spach, Anisochilus Wall. ex Benth., Plectranthus L’Her., Basilicum Moench, Orthosiphon Benth., Ocimum L. and Platostoma P. Beauv. Five species and 2 varieties are new to science. Study of pollen was undertaken to investigate the relationships between Ocimeae in continental South East Asia and Africa. The Asian genus Anisochlius and the other related African genera were chosen for this study. The pollen morphology is shown to be rather homogeneous and can only be divided into two types. A molecular approach was adopted in order to resolve generic and subtribal delimitation within the tribe Ocimeae and to investigate the relationships between the Asian, African, and New World members of the tribe. The trnL-trnF (trnL-F) region of the plastid genome was selected for this study. A large number of closely related Asian, African, and New World members of Ocimeae in various genera representing all currently recognised subtribes, and covering wide ranges of vegetative and reproductive morphology, were sampled for this study. Ninety-six accessions representing 92 taxa were selected. The data from the trnL-F region resolves the position of Isodon, previously regarded as incertae sedis, as sister group to the remaining Ocimeae. The subtribes Hyptidinae, Plectranthinae and Ociminae each form a clade but the relationships at generic level within each subtribe are still poorly resolved. The small Asian genera, Nosema, Mesona, Acrocephalus, Ceratanthus and Geniosporum are recognised as Platostoma. Ocimeae species in continental South East Asia are most common in rather dry and open habitats. There are very few Ocimeae in continental South East Asia in common with Malayan taxa.


 

Altingia siamensis, an apomorphic member of the Altingiaceae

David K. Ferguson

 

The Altingiaceae (Altingia, Liquidambar, and their probable intergeneric hybrid Semiliquidambar) all bear pendulous fruiting heads. The capsules open loculicidally to release the winged seeds. These are shaken free by gusts of wind, which cause the fruiting heads to swing to and fro on the long peduncle. Most Altingiaceae produce spheroidal fruiting heads. While the distal, downward-facing capsules release their seeds with ease, those capsules close to the point of attachment of the peduncle open upwards and therefore do not dehisce their seeds quite so easily. Such fruiting heads are known since the end of the Palaeocene (55 million years ago). On the other hand, a few species of Altingia (A. gracilipes, A. siamensis) produce hemispheroidal to turbinate fruiting heads, in which all the capsules face the ground in the mature state. This results in a more efficient dehiscence. Moreover, being smaller, these are less costly to produce and can be considered to represent an apomorphic state within the family. Since such fruiting heads have no known fossil record, they may have evolved in the comparatively recent past.


 

Coastal Vegetation on Sandbars in Narathiwat, Peninsular Thailand

Chukiat Laongpol, Kitichate Sridith & Kunio Suzuki

 

A phytosociological classification of the coastal vegetation of Narathiwat was performed using the Zurich – Montpelier School concept and method. The study included the terrestrial natural vegetation that has been left as isolated patches on the sandbars parallel to the seashore in Narathiwat. Twelve study sites were marked and the vegetation types are discussed. The profiles of the vegetation gradient across the sandbars are discussed.


 

Eriocaulaceae in Thailand

Amornrat Prajaksood, John A.N. Parnel1, Pranom Chantaranothai & Achra Thammathaworn

 

In Asia and hence Thailand, there is only a single genus of Eriocaulaceae present, Eriocaulon L. Members of the family are of little economic value and have been little studied. However, between 1954 and 1974, 13 new species were reported from Thailand. Therefore, it is clear that much remains to be done to assess the diversity of the Eriocaulaceae in Thailand. During a preliminary study of the family in the Northeast of Thailand, based on morphological, anatomical, and palynological data in 2001 it was found that ecology had a large impact on morphological characters. Thirty-four species of Eriocaulon were enumerated, 6 of which were new records for Thailand and 13 of which were unidentified species, some of which appear to be new to science. All species were described and photographed. Considerable, and taxonomically useful, variation was found in floral morphology. Anatomical study of the leaf surfaces and transection of leaves and scapes from eight species showed interspecific differences in the outline of the outer tangential wall of the epidermis, in the type of trichomes, in the arrangement of mesophyll, in the type of cells in the bundle sheath of the scape and in the number of buttresses in the scape. All of the 12 species whose pollen morphology was examined showed simple syncolplate grains, which are spheroidal, 15-30 m m in diameter, spiraperture with parallel spirals and with the sexine echinate. It was concluded that the structure of the pollen does not provide a satisfactory framework for classification within the genus. It appears that many new species await description in Thailand and that conventional morphological and anatomical methods provide useful and novel taxonomic data. For the current project, 953 specimens from 10 international herbaria comprising 351 collections of 34 species from Thailand have been accumulated. A herbarium database, a database enabling phenetic analysis and a database enabling synthesis of descriptions have been constructed. Field trips to selected National Parks and other areas will be held from September 2002 to January 2003. Subsequently, morphological, anatomical and molecular studies will be conducted so as to produce an account of the family for the Flora of Thailand.


 

Taxonomy of Southeast Asian Convolvulaceae

George W. Staples

 

The family Convolvulaceae comprises 23 genera in Thailand and an estimated 90-100 species, with perhaps 10-12 infraspecific taxa recognized. Biogeographically, a number of widespread species are found in Thailand and adjacent countries and other species were described as narrow endemics. It is anticipated that additional species await discovery and description. A regional study of the family is necessary to identify redundancy in names, rectify the nomenclature, and recognize genuinely undescribed species. Members of the family are distributed throughout the country's seven floristic regions. Genera particularly rich in species include Argyreia (18-25 species), Ipomoea (29 species), and Merremia (11 species). A color slide overview of selected Thai taxa accompanies the oral presentation. Recent molecular studies have called into question the validity of several genera long recognized in tropical Asia. The impact of these new findings on floristic studies remains to be evaluated. Should all species of Argyreia, Blinkworthia, Rivea, Lepistemon, and Stictocardia be submerged into Ipomoea, for example? Is such drastic lumping practical for users of regional/national floras? How does one accommodate sweeping changes in taxonomic concepts during the course of long-term floristic projects such as the Flora of Thailand? The challenges to be addressed in the course of preparing the account of Convolvulaceae for the Flora of Thailand, then, are twofold. First, to rectify the species-level nomenclature on a regional basis and describe heretofore unnamed species. And secondly, to group the species into meaningful genera in light of a flood of new molecular data that suggest that a number of long-established generic concepts are polyphyletic or paraphyletic.

 

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