Research Article |
Corresponding author: Andreas Berger ( andi.berger@univie.ac.at ) Academic editor: Andre Simões
© 2023 Andreas Berger.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Berger A (2023) Solved at last: The Philippine endemic Psychotria philippensis is a synonym of Scyphiphora hydrophylacea (Rubiaceae, Scyphiphoreae). PhytoKeys 221: 95-116. https://doi.org/10.3897/phytokeys.221.97766
|
Psychotria philippensis (Rubiaceae) was described by Chamisso and Schlechtendal in 1829, was the first Psychotria name published for the Philippines and is currently considered a Philippine endemic. The name remained in a taxonomic limbo for almost two centuries as it was variously accepted, synonymized or considered obscure, probably because the type specimen in the Berlin herbarium was destroyed and no original material has survived or is currently known. A combined analysis of the information on morphology, type locality and ecology contained in the protologue and a review of relevant literature on the study of the name by various authors over the last two centuries finally clarified the identity of P. philippensis. The name is confirmed here as a synonym of the rubiaceous mangrove Scyphiphora hydrophylacea, as first proposed by Schumann, one of the authorities of the family in the late 19th century, and the application of P. philippensis is fixed by neotypification. This reduces the number of Philippine species of Psychotria by one, but fortunately, this is not happening through extinction, as has been the case with too many species of the highly endangered Philippine flora. In addition, the history of the discovery and study of S. hydrophylacea and its synonyms are described in detail, and one lectotype and one neotype are designated.
Chamisso, herbarium history, Paleotropical Rubiaceae, The Philippines
The Philippines is one of the world’s top 25 biodiversity hotspots and one of the eight “hottest hotspots” in terms of endemic species and habitat loss (
Among the genera revised recently in the Philippines, is Psychotria (Psychotrieae), the largest and most complex genus of Rubiaceae in the Philippines and elsewhere.
With few exceptions, all of the 110 remaining Psychotria species are probably endemic to the Philippines, but a full assessment would require a better knowledge of the Southeast Asian and especially the Bornean species. They are predominantly found in primary forests and have narrow distributions making them prone to extinction. Following a drastic decline in primary forest cover over the last century, many species have not been seen for decades, leading
Five Psychotria names could not be assigned in the revision of
A year after its publication in 1829, Psychotria philippensis was already in use and was included in the Prodromus of
Karl Moritz Schumann (1851–1904), professor of botany and curator at the Berlin herbarium (B), contributed the family Rubiaceae to Engler’s “Die Natürlichen Pflanzenfamilien”. He was the first to place Psychotria philippensis in the synonymy of the rubiaceous mangrove tree, Scyphiphora hydrophylacea (
Most of the Berlin herbarium was destroyed during World War II (
The identity of Psychotria philippensis as a synonym of Scyphiphora hydrophylacea is finally established here by a combined analysis of morphological and ecological information in the protologue and an analysis of the historical studies of the name by various authors. Furthermore, the application of the name is fixed by neotypification. This reduces the number of Philippine species of Psychotria by one, but fortunately, this is not happening through extinction, as has been the case with too many species of the highly endangered Philippine flora.
The monotypic Scyphiphora is unusual within Rubiaceae in a number of ecological and morphological characters and is surveyed in detail by
The fruits of Scyphiphora are somewhat reminiscent of those of Psychotria. Both genera have bilocular drupaceous fruits, but Psychotria has fleshy, usually red, bird-dispersed drupes, usually with two one-seeded pyrenes embedded in the fruit pulp. When fresh, these fruits are more or less globose to ovoid or obovoid, and the longitudinally ribbed pyrene surface becomes apparent only in dried fruits (e.g.,
Meanwhile, the fruits of Scyphiphora are drift fruits adapted for sea dispersal, a rare dispersal mechanism in the family, otherwise found in few other members of the family that occur in coastal vegetation, for example, in Guettarda speciosa. The fruits of Scyphiphora are two-locular with two superposed ovules per locule, one ascending, the other descending. When the fruits are mature, they are elongated, dry, brownish and strongly longitudinally ridged. Most of the pericarp and the prominent ribs are composed of mesocarp, which consists of dead, thin-walled, lignified cells. Their lumina are connected by numerous pits and are probably air-filled to increase their buoyancy. The skin-like exocarp is thin, parenchymatic, dry and usually detaches to some extent when the fruits mature. Finally, the endocarp is thin, dry, and heavily sclerified, enclosing each of the two locules. In mature fruits, the seeds are connate by layers of parenchymatic cells, the fruits therefore do not separate into mericarps and the seeds are dispersed together. As pointed out by
Between August 1815 and August 1818, the Chancellor of the Russian Empire, Count Nikolai Romanzoff (1754–1826), commissioned an expedition around the world on the Russian brig Rurik under the command of Captain Otto von Kotzebue (1787–1846). In addition to their primary goal of finding the Northeast Passage from the Bering Strait to the Atlantic Ocean, they aimed to make scientific collections, for which they hired the famous poet and belated botanist Ludolf Karl Adelbert von Chamisso (1781–1838; see
In his first report to Romanzoff,
Chamisso donated a complete set of specimens from the expedition on the Rurik to the Berlin Herbarium (B). As stipulated in his will, an additional set of “1,800 plant species” was given to his successor at B, Johann Friedrich Klotzsch, who also donated them to the herbarium (
In 1840, two years after his death, Chamisso’s private herbarium, which contained up to 12,000 species and 60,000 specimens of his and many of his contemporary collectors (
= Epithinia malayana Jack, Malayan Misc. 1(5): 12–13. 1820. ≡ Scyphiphora malayana (Jack) Bedd., Fl. Sylv. S. India Forester’s Man. Bot.: cxxxiv–3, tab. 29., fig. 5. 1874, nom. inval. Type: Singapore. Singapore Island [protologue: “Found in Mangrove swamps on the Island of Singapore.”], s.d., W. Jack s.n. (lectotype, designated by
= Psychotria philippensis Cham. & Schltdl., Linnaea 4(1): 21–22. 1829a. ≡ Uragoga philippensis (Cham. & Schltdl.) Kuntze, Revis. Gen. Pl. 2: 962. 1891. Type: Philippines. Luzon, Calabarzon Region, Cavite Province: Noveleta [protologue: “Legimus in maritimis circa Tierra-alta Luçoniae.”], 1817–1818, L. K. A. von Chamisso s.n. (type, B†). Neotype: Philippines, Palawan Province: Culion Island, August 1913, L. Escritor s.n. in Merrill: Species Blancoanae 635 (neotype, here designated: US [00624079]; isoneotypes: L [L.2962064], P [P03972577], W [W 0131765]).
= Ixora manila Blanco, Fl. Filip.: 60–61. 1837. Type: Philippines. Palawan Province: Culion Island, August 1913, L. Escritor s.n. in Merrill: Species Blancoanae 635 (first-step neotype, designated by
= Hydnophytum costatum Drake, J. Bot. (Morot) 9: 240–241. 1895. Type: Vietnam. Quảng Ninh Province: Surroundings of Quảng Yên [protologue: “Environs de Quang-Yen, au milieu des palétuviers (685).”], August 1885, B. Balansa 685 (lectotype, designated by
Indonesia. Java, Jawa Barat: Anyer [protologue: “Hydrophylax. Collect. Banks.”], 2. Oct. 1770, unknown collector in J. Banks s.n. (lectotype, here designated: BM [BM000945301]).
Psychotria philippensis was published in a series on the botanical results of the Romanzoffian expedition on the Rurik prepared by
Chamisso noted that the lush forests around Tierra Alta extend from the mountains to the coast, where “Rhizophora and other trees reach into the sea” (
The type collection of Psychotria philippensis (apparently mentioned by him as one of the “other trees” in the remark quoted above) can thus be dated and localized to the mangroves around Tierra Alta and a period of about two weeks. According to information on the neotype, US 00624079, Scyphiphora hydrophylacea was already extinct in the entire Manila Bay region by around 1913, where it was once widespread (
After the destruction of B, where Schumann and Merrill had seen the only known type specimen, there should have been additional original material of Psychotria philippensis found in HAL and LE, which hold the largest extant parts of Chamisso’s herbarium (see above). However, no specimens are currently known in either of these herbaria (HAL:
Therefore, the name Psychotria philippensis is neotypified here, fixing the application of the name after nearly two centuries of uncertainty (ICN, Art. 9.8, 9.13;
For example,
According to a letter preserved at the United States National Herbarium (US), Merrill prepared 15 sets of his “Species Blancoanae”, each with 1046 specimens, and sent the first to US. Furthermore, he stated that the set at US was the only set that included original data such as field labels or notes and typewritten drafts of the treatments in the “Species Blancoanae”. According to
Although the above-mentioned gathering “Species Blancoanae” 635 is not from the Manila Bay, it serves as an excellent neotype for Psychotria philippensis because the gathering has duplicates in many herbaria and agrees with both Merrill’s concept of Scyphiphora hydrophylacea and his interpretation of the type of P. philippensis as its synonym. Therefore, a specimen of the gathering is here designated as the neotype of P. philippensis and the second-step neotype of Ixora manila.
With the application of Psychotria philippensis fixed, some further notes on Scyphiphora and Scyphiphora hydrophylacea seem useful. As to the type of genus and species, the names were published by the German botanist Carl Friedrich von Gaertner (1772–1850, original German orthography Karl Friedrich von Gärtner) in a “Supplementum” (
J. Gaertner’s collection of fruits and seeds is kept in the herbarium of the University of Tübingen (TUB), as is the herbarium of his son, who added to his father’s carpological collection and kept his own herbarium (
Two specimens, both mounted together on one sheet, are curated there as types of the name. The sheet is annotated in pencil as type of Scyphiphora hydrophylacea with the place of publication of the name. The two specimens are labelled ‘1’ and ‘2’ in black ink on the mounting tape at the base of the shoots. The numbers correspond to meagre annotations of locality and collector on the verso of the sheet in the upper left corner, written in black ink, as was common practice in many herbaria at that time. These annotations are here-interpreted as being in the hand of Samuel Törner, who was employed as amanuensis in the Banks herbarium from 1792 to 1797 (
Specimen ‘1’, BM 000945301, mounted on the upper left side of the sheet and annotated on the verso ‘1. Java prope Angerpoint. J. B.’, is a small fragment of a fruiting branch with a single leaf. ‘J. B.’ refers to Joseph Banks and links the specimen to James Cook’s first voyage aboard HMS Endeavour from 1768 to 1771, which is confirmed by a printed label of a later date reading ‘Java 1770–71 Banks & Solander’. The specimen was collected at ‘Angerpoint’, here identified as the present-day coastal town of Anjer or Anyer on Java, a natural harbor and important victualling station during the passage of the Sunda Strait. The diaries and travelogues of Cook and Sydney Parkinson (1745–1771), Banks’ illustrator (
Specimen ‘2’, BM 000945302, consists of four flowering branches and is annotated ‘2. Paolo Candor. Dav. Nelson’. It was collected by David Nelson (1740–1789), who participated in Cook’s third voyage aboard HMS Resolution (1776–1780) on behalf of Banks. The modern transcription of ‘Paolo Candor’ is Pulo Condor, now Côn Sơn Island, Vietnam. The gathering can be dated to 21–28 January 1780, based on
Banks and his collaborators had already collected Scyphiphora hydrophylacea in flower and fruit in Australia, which the Endeavour expedition visited before returning home via the Dutch East Indies and the Cape of Good Hope (
Another notable holding of Scyphiphora hydrophylacea material at BM is a long-unpublished watercolor by Ferdinand Bauer, made during the 1801–1803 circumnavigation of Australia on HMS Investigator under Captain Matthew Flinders. The watercolor shows a complete specimen with analysis of flowers and fruits, and was based on gatherings from the Northern Territory, also in the library of the Natural History Museum in London (Botany Library no. 70, Admiralty Library no. 122; see
The materials of the Investigator expedition (1801–1803) were definitely not available at the Banksian herbarium during C. F. Gaertner’s visit in 1802. It is also unlikely that the Australian materials of the Endeavour expedition (1768–1771) were seen by him, although they were surely accessioned in a timely manner after Banks’ return. The specimens were gathered under the herbarium name ‘Ixoroides littoralis’, and there is no reference to that name in the protologue of Scyphiphora hydrophylacea, where the material seen by Gaertner in the Banks herbarium is instead referred to the genus Hydrophylax L. f. (Rubiaceae: Spermacoceae). The only species currently assigned to that genus, Hydrophylax maritima, inhabits sea shores in India, Sri Lanka, Bangladesh and the western Thai part of the Malay peninsula. It has indehiscent fruits that superficially resemble Scyphiphora (e.g.
C. F. Gaertner described and illustrated the fruits of Scyphiphora hydrophylacea, but made no mention of the flowers (
A few years after
Finally, the plants were again described as Hydnophytum costatum Drake (
Selected and more or less useful historic and contemporary information and illustrations on Scyphiphora hydrophylacea can be found in chronological order in the following publications, some of them under synonyms added in parentheses:
Financial support for work at the Muséum National d’Histoire Naturelle (MNHN), Paris, France was provided by Synthesys+ (FR-TAF-8439) for which I express my sincere gratitude. In this regard, I would like to thank my host Florian Jabbour, Rubiaceae curator Sovanmoly Hul, and Synthesys+ coordinator Jonathan Blettery for their kind support in organizing the visit, help with the herbarium collections, and making the visit enjoyable both during and outside work. Further thanks go to Christian Bräuchler (W, Natural History Museum, Vienna) for enabling access to the collections, and to Uta Grünert (TUB, University of Tübingen) and Larisa Orlova (LE, Komarov Botanical Institute, RAS) for searching for type specimens. Open access funding was provided by the University of Vienna. Last but not least, I would like to thank the two anonymous reviewers whose constructive comments significantly improved the manuscript.