Malesian Euphorbiaceae Newsletter 7

December 1997

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Introduction

Changes

Training

Progress

Flora of Thailand

Databasing

Genera and Species to be Revised

Revised Genera

The revision of the Malesian Euphorbiaceae is still progressing steadily. During the last half year progress in the number of revised genera has been considerable, but the number of revised species is still low.

Luckily, Petra Hoffmann finished one of the larger genera, Antidesma, and Dr. Whitmore notified me that he is working on the Philippines species of Macaranga. I, myself, have started with the revision of Glochidion, the largest genus in the Malesian region. Thus in the future a few large genera will be finished and the number of revised species will increase dramatically.

However, it is still very unfortunate that many people, who promised to make revisions, still show no signs that they will keep their promises. Therefore, I will start to follow a slightly different way of tackling the revision of the Malay Euphorbiaceae. If people are willing to revise a genus which has already been assigned to somebody and they show that they will do so in due time, then I will reassign the revision to another contributor. Of course I will only do this after having contacted the first listed contributor. Hopefully, this will upset a few people and get things going. In the future plans exist to tackle Breynia and Croton.

The above part may not sound to cheerful, however developments are still positive. For instance, the newsletter, especially after the last issue with the list of Malesian and Thai taxa, has become very popular. This is a gratifying development, even though the production time will increase. It is somewhat surprising, because the newsletter is only meant for contributors as a kind of news update and it does not contain any scientific work.

Changes

The genus Securinega will be treated sensu Webster. This means that the real Securinega is limited to Madagascar, Reunion, and Mauritius (c. 5 species). The Malesian species belong to the genus Flueggea (c. 14 species in all tropics). The two genera not only differ in pollen morphology and seed anatomy, but also in wood anatomy (Baas, pers. comm.). Up to now the name Securinega was still used because Airy Shaw always referred to this name in his floral treatments. Christine Barker in Kew will revise this genus for Flora Malesiana.

Synostemon will be reduced to Sauropus, this is conform Airy Shaw’s revision of the Australian species (Kew Bull. 35, 1980, 685). Synostemon bacciformis (L.) G.L.Webster will become Sauropus bacciformis (L.) Airy Shaw. Synostemon should have free sepals, and Sauropus a calyx, but this difference is too weak to maintain both genera.

In the autumn of 1996 another regional training course in plant systematics for S.E. Asian countries was organised in Bogor, Indonesia. The course was funded by the MAB programme of UNESCO, the MacArthur Foundation, the Indonesian Science Foundation, and Leiden University. Fourteen participants (Indonesia, Malaysia, Philippines, Thailand, and Vietnam) and six Indonesian M.SC. trainees followed the five week course. The fundamentals of plant description, key construction, plant collection, phenetics, phylogenetic analysis, biogeography, species concepts, and evolution were demonstrated. Seven participants revised small genera of Euphorbiaceae for Flora Malesiana (see below).

The course is given every two years, the next one will be scheduled for 1998, perhaps after the Flora Malesiana Symposium in Malaysia. However, the course had to be cancelled two times due to a shortage of funds and this will also be the problem next year.

Petra Hoffmann finished the revision of the Thai and Malesian species of Antidesma. This is one of the major contributions to the Flora Malesiana treatment of the Euphorbiaceae. This project was funded for two years by the European Union and for one year by the Netherlands Science Foundation. Petra has worked very hard, 286 names were covered, which were originally spread over 110 taxa. After the revision of more than 7,000 specimens (12,000 duplicates) only 70 taxa are still recognised, 5 of them are new. The results will be published in a variety of articles: new taxa in Novon, the complete revision by Kew, the Thai species in the Thai Forest Bulletin and Flora of Thailand, the Malesian species in the Tree Flora of Sabah and Sarawak and Flora Malesiana. Under consideration is the publication of new lectotypications in Kew Bulletin. One of the difficult tasks was the construction of a key to the species and the results are very good: an illustrated dichotomous and multi-access key. Trials with the dichotomous key, usually the most difficult to use, resulted in satisfactory identifications. Presently new, high quality illustrations are being made which will be included in at least the Kew publication, but probably also in the different floral treatments.

Prof. Nguyen Nghia Thin and Vu Hoai Duc’s revision of the genus Strophioblachia has been updated and submitted for publication in Blumea. Only one species, though variable, could be distinguished.

Paul Forster (Australia) provided three manuscripts with a revision of the genera Choriceras (1 species), Fontainea (2 species), and Petalostigma (1 species). Some of the species are new and they will be published soon.

Dr. T.C. Whitmore (Cambridge) wrote that he is busy revising the Philippine species of the large genus Macaranga. The Philippines is one of the areas in Malesia for which no Euphorbiaceae revision exists as yet, only an uncritical check list (Airy Shaw, An alphabetical enumeration of the Euphorbiaceae of the Philippine Islands, 1983, Kew Botanic Gardens) is present. The same situation more or less exists for Central Malesia (Sulawesi, Moluccas, and Lesser Sunda Islands), but Airy Shaw managed to make a more critical check list for this area (Airy Shaw, Kew Bull. 37, 1982, 1--40).

Christine Barker (Kew) has finished the revision of Margaritaria (2 species and a resurrected variety) and continues with the revision of Flueggea.

Metilistina Sasinggala (Bogor) has revised Galearia for Flora Malesiana. She recognises 6 species (one subdivided into 2 varieties). Unfortunately the manuscript is still in Indonesian. Hopefully, she will prepare an English version in the near future.

The same applies to the revision of Ptychopyxis by Cornelis Sri Murdo Yuwono (Bogor). He recognises 12 species, but his manuscript is also still in Indonesian.

Muzzazinah (Bogor) has finished a revision of the Malesian species of Koilodepas. She recognises 9 species (with one subdivided into 2 varieties), one of which is new. Fortunately, her manuscript is in English, and will hopefully be published in due course.

Wolfgang Stuppy, on a visitor’s grant of the Netherlands Science Foundation, has revised the genera Aleurites (2 species), Reutealis (1 species), and Vernicia (3 species). The latter two genera in cooperation with Ms. Parinyanoot Klinratana (Thailand) and Ms. Maria Carmela Posa (Philippines), two participants in the last training course in botany for S.E. Asian countries in Bogor, Indonesia. A phylogeny of the three genera (with several outgroups) showed that the delimitation of Airy Shaw can be maintained (formerly all genera were united into Aleurites). Reutealis is not intermediate between the other two genera but basal to them. Presently, Wolfgang is preparing a datamatrix to tackle the generic delimitation in the tribe Acalypheae.

Sarah Bollendorff, a student from Luxembourg, is presently revising the species of section Polyadenii in the genus Mallotus in Leiden. Unfortunately, the species are difficult to recognise, the major characters are in the different fruit types and not so much in vegetative and floral parts.

Sofia Sevilla, an exchange student in the Erasmus programme of the European Union, is revising the genera Agrostistachys and Chondrostylis for Flora Malesiana. The two genera are not closely related, but they are often confused. Part of the unidentified Agrostistachys material seems to be a new species in Chondrostylis.

Peter van Welzen has finished a revision of the genera Homonoia (2 species, 1 in Malesia), Lasiococca (3 species, one in Malesia), Spathiostemon (2 species), Clonostylis (not a synonym of Spathiostemon, one species), Ricinus (introduced in Malesia, 1 species), Wetria (2 species). Most of the data were used to make a phylogenetic analysis of the subtribe Lasiococcinae (comprising the first three genera). Presently, the same is being done for the subtribes Doryxylinae (Doryxylon, 1 species; Melanolepis, 2 species; Sumbaviopsis, 1 species, already finished, only the monotypic Thyrsanthera left) and Chrozophorinae (only containing Chrozophora). According to the literature most of these groups show a too high degree of splitting, quite a few of the genera are monotypic, just like the subtribe Chrozophorinae, while the genus Thyrsanthera may be intermediate between both subtribes. Balakrishnan (Bull. Bot. Surv. India 9, 1967, 56--58) already suggested that Doryxylon and Sumbaviopsis may easily be united. N.B. The revision of Lasiococca was in cooperation with Nguyen Nghia Thin and Vu Hoai Duc. The revision of Melanolepis was in cooperation with three participants in the Bogor course: Ms. Kartika Ning Tyas (Indonesia), Ms. Eviyarni (Indonesia), and Mr. Ferdinand Gaerlan (Philippines).

After the revision of the Doryxylinae and Chrozophorinae Peter van Welzen will start with the largest Malesian genus Glochidion.

Two other participants in the Bogor course, Mr. Nguyen Quoc Dung (Vietnam) and Mr. Richard Chung Cheng Kong (Malaysia), in cooperation with Peter van Welzen, revised the species of the genus Manihot (2 introduced species). This paper has been accepted for the journal Rheedea.

Ferry Slik, revising two sections of Mallotus, is presently doing fieldwork in Kalimantan (Indonesia, Borneo). He is investigating which species of Macaranga and Mallotus may be useful as indicator species for certain types of (disturbed) habitat, especially the different stages in secondary forest are important in his research.

Raoul Haegens will finish the revision of Baccaurea at the beginning of next year, after which he will spend the remainder of 1998 to prepare a phylogeny of the genus and to examine the historical biogeography of the genus in relation to two animal groups (dragon flies and cicadas). The latter analysis will show via which pathways plants and animals could have reached New Guinea from S.E. Asia mainland.

Anne Schot has temporarily stopped the finishing touches to her revision of Aporosa. The birth of a beautiful daughter has delayed her work. Congratulations!

September 1997 was the start of a three year scheme to revise the Euphorbiaceae for Thailand. It is a Thai funded project and this in spite of the present bad economy! Many collaborators will try to finish this project in time, most of them are Thai. Co-ordinator is Mrs. Dr. Kongkanda Chayamarit (BKF, Forest Herbarium, Royal Forest Dep., Bangkok 10900, Thailand, email: kchayama@mozart.inet.co.th). Peter van Welzen (L) will help to co-ordinate and he is one of the few foreigners active in the project. Other foreigners involved are Hajo Esser (HBG) and Prof. Larsen (AAU). However, more volunteers are welcome. If you like to participate, please contact Phi Kongkanda. At the end of the project the information has to be on the internet, but it will also be published in the Thai Forest Bulletin and in the Flora of Thailand series.

This year Peter van Welzen spent one month in Bangkok to make a start with the revisions. Due to overlap with the Flora Malesiana project 42 species could be revised. The revised genera are marked in bold in the list below.

In total 82 genera with about 400 species have to be revised. This means that about 10 % is finished now. This number will quickly increase as the revision of the Thai species of Antidesma, Aporosa, and Baccaurea are about to be finished together with a few smaller genera like Agrostistachys, Aleurites, Chondrostylis, Chrozophora, Thyrsanthera, Vernicia, etc.

Next to revision work the project also includes collecting. Especially the central, eastern and north-eastern part of Thailand are in need of better sampling. The budget of the project includes a reservation for this kind of work.

Those researchers interested to join the project can find the core collections in the following herbaria: AAU (Aarhus, Denmark), BK (Bangkok, Thailand), BKF (Bangkok, Thailand), C (Copenhagen, Denmark), K (Kew, England), KYO (Kyoto, Japan), and L (Leiden, Netherlands).

The following genera have to be revised (in bold: finished; in italics: to be revised by L staff):