The Angraecoid Alliance

Spring 2013 THE ANGRAECOID ALLIANCE Angraecum stella-africae by Isobyl la Croix Volume 2: The 21st World Orchid Conference plants of Bulbophyllum josephii. will be held in Johannesburg in There were several mature plants and Issue 2 September 2014. The logo depicts some young ones on the trunk, one in Spring 2013 Angraecum stella-africae, so it seems flower and others in bud. Each an appropriate time to write about this mature plant bore a single large, little species. green, winged capsule, apparently I first became aware of this species from the previous year, and an old Inside this issue: when I was given a copy of Southern brown one that had shed its seed, African Epiphytic Orchids by John presumably from the year before that. Angraecum 1 Ball, where it is listed as Angraecum One or two other trees had a few stella-africae sp. (Renny 174). Like the other plants of the Angraecum and species covered in the book it is obviously none of the local people Ex-Situ illustrated by a life-size watercolour had been there recently to collect Conservation 3 painting by Patricia van de Ruit. It firewood, as we found one or two Update was known from what was then fallen branches carrying plants, which Transvaal (now Limpopo) in South we took home with us. Missouri Botanical Gardens: 25 years 4 Africa and there was an unconfirmed About 10 days later, Phillip Cribb, in Madagascar record from Zimbabwe. I thought the Kew orchid specialist, was on his what an attractive plant it was, but it way back from a conference in South never occurred to me that we might Africa and stayed with us for a couple World Orchid later find it ourselves. of days. I showed him a plant of the 5 Conference We were living then in southern Angraecum that was now in flower Malawi but took any opportunity we and asked if it now had a name. He could to visit the north, which was told us that the species had never Journal Review 5 less densely populated and had more been described and there and then, woodland and forest left. On one such took measurements. That plant Jumellea visit in January 1982 we (my husband became the type specimen of 6 arachnantha Eric, son Tim and myself) stopped at Angraecum stella-africae. I have what looked a promising bit of often thought since what a lucky Membership Brachystegia woodland a few miles chance it was that he was staying 7 Card south of the town of Mzuzu to see with us when the plant flowered, as what we could find. A large white the flowers lasted for less than two flower caught our attention, and there days. was “Angraecum sp.” flowering on the lichen-covered trunk of a tree at ˃˃continued on pages 2 and 3 about eye-level, accompanied by Page 2 The Angraecoid Alliance ˃˃continued from page 1 Angraecum stella-africae belongs to Section Perrierangraecum which, apart from this species and the rare Zimbabwe endemic Ang. chimanimaniense (also featured in John Ball’s book as Angraecum sp.) is confined to Madagascar. It is related to well-known species such as Ang. cucullatum and Ang. rutenbergianum. Plants are small, with a very short stem and linear, dark green leaves 3-5 cm long. The roots are smooth, 2-3 mm in diameter and cling close to the bark. The inflorescences are single-flowered and arise below the leaves. The flowers are glistening white, or sometimes with greenish-white sepals and petals, and at almost 5 cm across are large for such a tiny plant. The sepals are up to 25mm long, the petals slightly shorter. The lip is much the most prominent part of the flower, about 26 x 15 mm, with a slender spur 12-15 cm long. The ovary is bright green and winged, triangular in cross section, and starts to grow in size as soon as the flowers are over. Sometimes buds seem to be on the point on opening, then collapse, while the ovary continues to develop. Although the white, long-spurred flowers look as if they should be moth-pollinated, they seem always to be self-pollinating. I was never able to work out whether some plants had buds that never opened or whether this was dependent on conditions – perhaps too humid, or not humid enough. We subsequently found a single plant on a fallen branch in a forest reserve some distance further south at an altitude of 1250 m, slightly lower than the 1,500 m altitude of the original find. Then two years later, a friend of ours found a plant on a fallen branch of a tree in tall riverine forest near the base of Mount Mulanje in the south of Ma- lawi. He estimated it had been growing high up on the tree. The unconfirmed record from Zimbabwe was about 50 years old and the species was presumed to be extinct there, but in 2004, Bart Wursten found a small colony of it in the Vumba mountains, growing in Brachystegia woodland in a situation very much like our ˃˃ Angraecum stella-africae Photograph courtesy of Isobyl la Croix Volume 2, Number 2: Spring 2013 Page 3 ˃˃continued from page 2 Mzuzu site and at the similar altitude of 1600 m. Again, many plants of various sizes were found on the one tree, with only a few more elsewhere. It is interesting to read that the flowers of these plants lasted for at least 6 days, although again they appeared to self-pollinate. Perhaps there is a genetic element in the length of time a flower lasts. Angraecum stella-africae is unusual in that it has a relatively wide geographical distribution (South Africa, Zimbabwe, Malawi) but in each country is found in very few localities. I hope it will continue to survive there. References Ball, J.S. (1978) Southern African Epiphytic Orchids. Conservation Press, Johannesburg. la Croix, I. .et al. (1983). Malawi Orchids, Volume 1. Blantyre. la Croix, I.F., E.A.S. & T.M. (1991). Orchids of Malawi. A.A. Balkema, Rotterdam. la Croix, I. & P.J. Cribb (1998). Flora Zambesiaca, Vol.11, part 2, Orchidaceae. Linder, H.P. & Kurzeil, H. (1999) Orchids of Southern Africa. A.A. Balkema, Rotterdam. Stewart, J., Linder, H.P., Schelpe, E.A. & Hall, A.V. (1982). Wild Orchids of Southern Africa. Macmillan South Africa, Johannesburg. Wursten, B. (2007) Angraecum stella-africae P.J. Cribb, the rediscovery of this rare orchid in Zimbabwe. Excelsa 21:37-38. Ex-Situ Conservation Project: The Ex-Situ Conservation Project is striding forward. Seed from the first species in the Ex Situ Conservation Project has been sent to the Atlanta Botanical Gardens in Georgia, USA. Angraecum birrimense will be the first species to be flasked there. Seed for two additional species is also available for flasking: Aeranthes peyrotii and Cryptopus paniculatum. Another member has generously offered the following species that are currently in flask: Aerangis fuscata, Aerangis kirkii, Angraecum arachnites, Angraecum dollii, Angraecum doratophyllum, Angraecum florulentum, Cyrtorchis praetermissa, Jumellea arborescens, Jumellea ibityana, Jumellea rigida and Rangaeris amaniensis. These species are already in flask; availability will be dependent upon demand and germination rates. There will be a cost (to be determined) associated with obtaining plants of these species. (For members outside of the U.S., the Alliance is working on securing the necessary export permits. You would, of course, need any import permits required.) So that we can focus our efforts on the species most in need of ex-situ conservation, please visit our facebook page to vote for species that should be given priority efforts. www.facebook.com/ www.angraecoids.org. For more information about any of these species or if you grow a rare or unusual angraecoid and would like to participate in the ESC project, please email [email protected] or write to 4507 Goldenacre Lane, Rogers AR 72758, USA. Page 4 The Angraecoid Alliance The Missouri Botanical Gardens Celebrates 25 Years in Madagascar This year, the Missouri Botanical Gardens, Ankafobe Forest is just a fragment of forest headquartered in St. Louis, Missouri, USA in the highlands of central Madagascar. celebrates its 25th anniversary of research and Ankarabolava-Agnakatrika Forest includes conservation efforts in Madagascar. Initially, the only remaining natural vegetation in the the primary focus was botanical research area and consists of a highly fragmented, including exploration and identification of lower elevation humid forest. Madagascar’s unique flora. Researchers and Ibity Massif is a quartz mountain in the students from around the world, including local central highlands. Malagasy students, have trained with and Makirovana-Tsihomanaomby Forest is worked for the Missouri Botanical Garden’s another fragmented, low-elevation humid (MBG) “offices” in Madagascar. forest located in northeastern Madagascar. In more recent years, MBG’s focus has Oronjia Forest, a fragment of dry deciduous widened to include a number of conservation forest on the northern tip of the island. activities. These include funding education and Pointe à Larrée is a peninsula on economic projects that correlate with more Madagascar’s eastern coast. effective land use. For example, MBG has Vohibe Forest, located in eastern worked with villages to develop farming Madagascar and is part of the Ankeniheny- techniques that improve harvest yield and do Zahamena Forest Corridor and is an almost not require tavy (slash-and-burn farming). pristine low-elevation forest. MBG has also funded projects that provice alternative sources of income that do not Maps, photographs and much more negatively impact the environment. information about the 11 specific conservation areas and about MBG’s work Perhaps of most interest to members of in Madagascar can be found at The Anngraecoid Alliance, MBG has http://www.missouribotanicalgarden.org/ established 11 conservation sites including: plant-science/plant-science/africa/ madagascar.aspx.

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