Jan Dirk Bastmeijer ( 22 October 1943 – 18 February 2022 )
Niels Jacobsen¹, Suwidji Wongso²
¹ Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
² Yayasan Konservasi Biota Lahan Basah, Raya Sawo Gg III No. 33, Surabaya 60218, Indonesia.
Cryptocoryne lost one of its leading experts when, after a few years of declining health, Jan D. Bastmeijer passed away in February this year.
Jan was born in Alkmaar, about 30 km NNW of Amsterdam, The Netherlands. After school and military service, he studied physics, mathematics, and astronomy in Leiden. A free time occupation was fishing in the canals of Leiden, such a passion that on his marriage to Cora Bastmeijer-Sneijders, his friends gave him a fishbowl with fish and plants. You could say this was a starting point of his fascination of aquatic plants, further promoted by a large aquarium given to him later by Cora. Jan would go on to be one of the leading experts on the Araceous genera Cryptocoryne and Lagenandra, on which he over the years published 90 articles and a unique website 「 the Crypts pages」: https://crypts.home.xs4all.nl/Cryptocoryne/index.html.
Jan’s formal training in physics, mathematics and astronomy led him to a job as teacher in the high school and the pedagogical academy in Emmen. He much enjoyed the challenge of teaching physics to children. Later, he came to the Windesheim University of Applied Sciences in Zwolle as teacher coach for physics and later studied computer science at CPIM in Eindhoven. During the years teaching in Zwolle his interest in aquatic plants was nourished by his involvement in the Dutch Aquarium Society, in Werkgroep Aquatische Planten (WAP), which held regular meetings, especially during colder parts of the year.
Cultivating plants has for centuries been a characteristic of the Dutch – just to mention their flair for producing enormous numbers of tulip cultivars and other bulbous plants. In decorating and cultivating plants in aquaria, there is even a ‘scaping class called ‘Dutch style’ which in short has the characteristic of an aquarium densely planted with different aquatic plants. Cultivating plants in an aquarium is one thing,
but when you want to communicate how you manage to grow them, you eventually need to know the name of the plants you are growing, otherwise there is no communication. Naming of the aquatic plants in the 1960s and 70s was not without problems, especially within the genus Cryptocoryne, where there were many problems in naming the many different plants that were imported in large quantities from SE Asia. Some were easy to grow while others proved more difficult or close to impossible in the then given circumstances.
Figure 1.
Jan D. Bastmeijer.
Ⓐ 2017.
Ⓑ Preparing a colour slide show at aquarium plant meeting 1996.
Ⓒ Philippines, Palawan, S of Tayay, collecting Cryptocoryne pygmaea Merr., B 790.
Ⓓ Sampling Fagus leaf peat soil in Emmen 2012.
Photographs mainly from Jan’s archives.
Figure 2.
Front page of Jan D. Bastmeijer’s web site ‘the crypts pages’.
Another aspect for Cryptocoryne was that then knowledge of the species did not really match the plants being imported. In Engler’s (1920) treatment of Cryptocoryne 4 species were listed from Sri Lanka, and with our knowledge today we accept 10 species, and a named natural hybrid. It has furthermore proven that these species are variable, and the propagation by stolons has resulted large populations made up of clones. Populations consisting of fixed clonal genotypes are a blessing and a nightmare for gardeners: when you have grown a certain clone for years in an aquarium you know it quite well, and speak with a certain authority about its identity, but the same clone grown under different soil and water conditions may look quite different. It furthermore proved that the Sri Lanka Cryptocoryne species were variable: C. wendtii De Wit is very variable with both diploid and triploid clones. A great morphological variation within this species formed a basis for many discussions about what is what. Within Cryptocoryne, although there are differences in leaf size, shape, and colour, it is in morphological characters of the spathe, and especially the limb, that provides the final taxonomical characteristics. So, you must make them flower before you can identify them, and flowering submerged aquarium conditions is not that frequent at all. You therefore must concentrate on development of methods to cultivate them to flowering condition. Jan’s contribution to all this was to make the plants flower, document the results, compare all flowering material, and build a case for identification.
During the 1960s and 1970s there was a strong interest and tradition in The Netherlands for keeping aquaria and of course plants, hence the journal ’Het Aquarium’. Regarding plants this interest was nourished by Prof. H.C.D. de Wit in Wageningen, publishing a number of articles about Cryptocoryne in ’Het Aquarium’ from 1958-1971, and a book on aquarium plants, which appeared in several editions, the latest in 1990; Bastmeijer 1989; Bogner & Bastmeijer 2001).
Besides being intrigued by the many different Cryptocoryne species in circulation, difficulties identifying them, no doubt challenged Jan’s mind set, developed from his education within physics, mathematics, and computer sciences – where everything is logic and possible to describe in logic terms. You need to have a consequent and logic approach if you want to make experiments with electricity or thermodynamics. So, Jan’s approach to Cryptocoryne was to obtain all available data, i.e., literature references and document plants and flowerings with colour pictures. Preserve the flowering plants as herbarium and alcohol specimens of (to be able to see size and shape of spathe and spadix), and of course document the origin.
All live plant accessions received a greenhouse accession number, and Jan had cultivated more than 1.700 Cryptocoryne and Lagenandra accessions over the years. His collection of literature accessions related to Cryptocoryne and Lagenandra and, e.g., related ecological subjects amounted to more than 1.000. His list of Cryptocoryne and Lagenandra specimens (world herbaria) and species/localities from literature and live plants amounted to more than 3.000.
His lists would look something like this:
Cryptocoryne nevíllii Hook.f., Nevill s.n., TYPE, Nov 1885, Sri Lanka, N 07’14’ E 081’34’ (cood approx. from map). Amparai district: Grukamana Tank near Wawinna. Only tip of spathe protruded above ground. Amongst grass, flowers November (1885) (Hook. 1898).
Cryptocoryne schulzei De Wit, coll.: Schulze 553, TYPE, 08 Sep 1970, Malaysia, Johor, 45 miles E of Keloeang.
With Jan’s teaching in computer science, it was of course natural for him to apply it to his work with Cryptocoryne, and the introduction of digital photography and development of the internet opened a completely new horizon of communication. Jan’s website ‘the Crypts pages’ quickly became a prime source of information and for communication. Building blocks of the web site are the description of each Cryptocoryne species, with a short introduction, a reasonable number of photographs, captions for the pictures and lastly a list of relevant literature references. This makes it easy for readers to see the basic data backing each species. The website was an up-to-date source of information for aquarists who wanted to identify plants they were growing, but also for plant enthusiasts in SE Asia wanting to know something about plants they found in nature. Any questions or contributions could be handled through e-mail.
The web site and the following contact correspondence with very many people was also a start of an increasing exchange of plants. Jan was of course up to date on the known species of Cryptocoryne, and it was only natural that Jan was involved in most of the identifications of new species cooperating with many people in getting new species published. This would be the early days of networking also leading to what we today would call citizen science. Jan keeping track of everything.
Presently the first dated folders on the website are from 1997, and naturally the most wellknown species followed quickly afterwards. After 2000 a number of species were quickly added, and they were added to as quickly as they were published. Around 2016 a little more than 80 taxa of Cryptocoryne were included in Jan’s list, and seven were waiting to be included. Today, only about six years later 105 named taxa (species, varieties & hybrids) are accepted.
Besides Jan’s work in documenting and the development of the website, Jan was also involved in aquatic plant meetings both in The Netherlands and in Germany, from the 1970’ies and onwards. The broad palette of contacts resulted in the first meeting at Cora and Jan’s house in Emmen for Cryptocoryne fans in 2000 with about a dozen participants. Next year the meeting was held in Waiblingen, Germany, and establishment of the European Cryptocoryne Society was a fact. These yearly meetings have continued ever since, each year taking place in a different place somewhere in Europe, the two years of 2020 and 2021 as internet meetings though, joint hosting from Hamburg and Stockach, Germany. The gathering starts Friday evening before dinner time and lasts till Sunday after breakfast. With general talks and discussions among participants, and presentations on various aspects of Cryptocoryne (and Lagenandra) – cultivation experiences, identifications, and discussions of the latest news – species – articles. A visit to the local botanical garden if such exists. Society build-up is simple: There is no board, no chairman, no annual fees, and no association laws. Each participant pays their own travel and hotel expenses. Everyone with surplus of plants brings them, labelled with data in separate plastic bags. There is a ‘plant market’ with free distribution where people can take what they want. There is always enough to go around. This free sharing of plants has been a general idea with Jan and within ECS. The only point in the agenda for the ECS meetings is to decide where the meeting is to be held next year. Even though Jan did not put himself in front during the ECS meetings, he was always a person the participants would consult about questions or seeking advice. He was a modest man always helping others with whatever he could. We have been many who have enjoyed the hospitality of Jan and Cora over the years in their hideout in Emmen.
Jan himself made one trip to SE Asia in May 1999. The Cryptocoryne species of Philippines had always been special interest. He visited the islands of Luzon, Busuanga, and Palawan together with Hersan Morco (Bastmeijer & Morco 2000). He continued to Singapore where people from Oriental Aquarium helped him visit Johor, Peninsular Malaysia. In Singapore he visited Bukit Timah Nature Reserve and found that the Cryptocoryne growing there was a natural hybrid new to science and it was named Cryptocoryne × timahensis Bastm. (Bastmeijer & Kiew 2001).
Over the years Jan’s interest in Cryptocoryne developed to a ‘full time’ hobby. He started off with growing plants in aquaria, where the front glass could be opened, and he could tend for his plants from the side. He had several aquaria on top of each other in his ‘office’ where he also kept his herbarium and alcohol collection, now transferred to the herbarium in ‘Naturalis’ in Leiden. Jan had a dream of having his own greenhouse where he could grow his aquatic/ amphibious Cryptocoryne.
He was fortunate to be able to retire at an early age and in 2003 he began to build a greenhouse in their garden. Well actually it was more of a growth chamber with a vast number of technical installations (his physics background and love for electrical gadgets) and light coming from one large window facing southeast and a smaller window facing southwest. There were tables where plants were grown in pots standing in 2 cm water or in 1-5 litre tanks where plants were more or less submerged. In wintertime plants received additional lighting and during summertime they were heavily shaded. During European summertime plants of the Cryptocoryne crispatula Engl. complex from Mainland Asia drop their leaves, and the plants were then stored in the ‘technical’ room under the greenhouse.
From the old days when Jan was cultivating Cryptocoryne in his office, he became a professional plant grower and taxonomist. During the years of cultivating Cryptocoryne in his office tanks he learned how to cultivate different species in such a way that he could bring them to flower, almost as he wanted. Moving into the new greenhouse he had the possibility to vary cultivation conditions even more and was able to cope with almost all new species that came into cultivation after turn of the millennium. He cultivated, e.g., C. sivadasanii Bogner very well, but flowering it in cultivation has yet to be seen – for any of us.
He learned to cultivate all the different Cryptocoryne species, and his contributions to the world can be seen from the publication list and from his website where any plant enthusiast immediately can obtain information and knowledge of Cryptocoryne species.
Figure 3.
Ⓐ Participants of the ECS-meeting in Göttingen, Germany, 2009, waiting at the bus stop on the way to the botanical garden.
Ⓑ ECS 2008 take home poster (A3) designed by Jan, of what was to become Cryptocoryne crispatula var. decus-mekongensis T.Idei, Bastm. & N.Jacobsen.
Ⓒ ECS 2009 take home poster of the in July by Takashige Idei recollected Cryptocoryne dewitii N.Jacobsen (first found in 1971 and described in 1977).
Figure 4.
Ⓐ The aquaria in Jan’s office around 1985.
Ⓑ The setup in 2004.
Ⓒ The alcohol collection, plant press material and colour slides below, and herbarium on top, in the office in 2006.
Figure 5.
Ⓐ The greenhouse 2007. Work facilities left and growth facilities right.
Ⓑ Jan’s technical installations computer controlled.
Ⓒ Practical work facilities a few m away from the plants, 2019.
Figure 6.
Long table in the greenhouse next to the window with more light requiring plants, 2010 (left to right).
Ⓐ Mostly Lagenandra.
Ⓑ Narrow leaved C. crispatula varieties and Sri Lanka species.
Ⓒ Sri Lanka species and various species in front.
Figure 7.
Ⓐ Mixed Cryptocoryne species and cultivation modes, Malesian species in tanks. 2017.
Ⓑ Malesian species submerged with Fagus leaf peat as substrate, 2010.
Figure 8.
Setup in greenhouse when there is not enough space on the tables:
(A – C) New accessions and extras are given extra space in mostly 5 l tanks on the floor, 2010.
Figure 9.
Ⓐ Pot cultivation of mostly some newer Malesian accessions; arrow shows the tetraploid C. ciliata (Roxb.) Schott var. bogneri N.Jacobsen, type collection. 2018.
Ⓑ Mainly C. crispatula varieties from the Mekong region. They develop leaves during winter in northern Europe, March 2011.
Figure 10.
One of the six new species from Kalimantan described by Wongso et al. (2017), Cryptocoryne bastmeijeri Wongso, SW 1567.
Ⓐ Roads to discover new species are not always easy.
Ⓑ From type collection showing one of the typical ways of Jan’s cultivation methods.
Ⓒ A chromosome number of 2n = 14 was the first record of this number for Cryptocoryne.
(D – G) Spathe pictures showing the typical way Jan would photograph and document a flowering plant. Scale 1 cm.
Figure 11. Ⓐ The ‘first’ aquarium still in use for maintaining various accessions under a different way of cultivation with among others Schismatoglottis prietoi P.C.Boyce, Medecilo & S.Y.Wong, Cryptocoryne crispatula var. balansae (Gagnep.) N.Jacobsen, C. lingua Engl., C. crispatula var. kubotae N.Jacobsen & Bastm., C. wendtii De Wit, C. cordata var. siamensis (Gagnep.) N.Jacobsen & Sookch. ‘Rosanervig’, C. affinis Hook.f., C. consobrina Schott, C. crispatula var. tonkinensis (Gagnep.) N.Jacobsen, C. sivadasanii Bogner and Bucephalandra sp., 2017.
Ⓑ Cora and Jan, 2017.
Ⓒ Jan and Josef, 1st ECS-meeting, Emmen, 2000.
Around 2017 Jan began to become ill and did not continue to update the website. At the moment possibilities of continuing and updating of Jan’s website are being investigated. But for now, you can find it on Crypts pages (xs4all.nl). For the new Cryptocoryne species, varieties, and hybrids not on Jan’s website, a list is provided in Table 2 with references and links to the original publications. Although becoming increasingly ill, Jan still contributed to the description of many of these new taxa.
Jan lived most of his life in the small town of Emmen, about 145 km NE of Amsterdam. Jan is survived by his wife Cora Bastmeijer-Snijders and their four children.
REFERENCES
Bastmeijer J.D. (1989). Zum 80. Geburtstag von Professor Dr. H.C.D. de Wit. Aqua-Planta 14(4): 136–138.
Bastmeijer J.D. (2022). The Crypts pages. https://crypts.home.xs4all.nl/Cryptocoryne/ Accessed March 23, 2022.
Bastmeijer J.D. & R. Kiew (2001). A New Cryptocoryne Hybrid (Araceae) from the Bukit Timah Nature Reserve, Singapore. Garden's Bulletin Singapore 53: 9–17.
Bastmeijer, J.D. & H. Morco (2000). Cryptocoryne pygmaea Merrill (Araceae) von Busuanga und Palawan (Philippinen). Aqua-Planta 25(3): 99–107.
Bogner, J. & J.D. Bastmeijer (2001). In Memoriam - H.C.D. de Wit (1909–1999). Aroideana 24: 3–5.
Engler, A. (1920). Araceae – Aroideae. Das Pflanzenreich IV.23.F.: 232–249, Leipzig.
Wit, H.C.D. de (1990). Aquarienpflanzen, 2. Auflage. Ulmer, Stuttgart.
Wongso, S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N. Jacobsen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo. Willdenowia
47(3): 325–339. https://doi.org/10.3372/wi.47.47314
Publications by Jan D. Bastmeijer
Arends, J.C., J.D. Bastmeijer & N. Jacobsen 1982. Chromosome numbers and taxonomy in Cryptocoryne (Araceae) II. Nordic Journal of Botany 2: 453–463.
Asih, N.P.S., S. Wongso, Hendrik, J.D. Bastmeijer, S. Reitel, K.R. Jensen, M. Ørgaard & N. Jacobsen 2022. New Cryptocoryne (Araceae) from West Kalimantan, Indonesia: a new species and a new interspecific natural hybrid. Aroideana 45(1): 296–312.
Bastmeijer, J.D. & B.E.E. Duyfjes 1996. Zwei Cryptocorynen aus dem Gunung-Leuser- National Park (Sumatra, Indonesien). 1. Teil. Cryptocoryne minima Ridley. Aqua Planta 21(4): 191–197.
Bastmeijer, J.D. & B.E.E. Duyfjes 1997. Zwei Cryptocorynen aus dem Gunung-Leuser- Nationalpark (Sumatra, Indonesien). 2. Teil. Cryptocoryne moehlmannii De Wit. Aqua Planta 22(2): 41 (cover), 43–50.
Bastmeijer, J.D. & B.H. Bouwmeester 1990 Cryptocoryne fusca. Het Aquarium 60(10): 267– 272.
Bastmeijer, J.D. & B.H. Bouwmeester 1992. Cryptocoryne fusca De Wit. DATZ 45(12): 788– 791.
Bastmeijer, J.D. & C. Kettner 1991. Cryptocoryne pallidinervia Engler. Aqua Planta 16(4): 121, 123–128.
Bastmeijer, J.D. & C. Kettner 1993. Die Cryptocorynen von Yahalawatta (Sri Lanka). Aqua Planta 18(1): 30–31.
Bastmeijer, J.D. & H. Morco 2000. Cryptocoryne pygmaea Merrill (Araceae) von Busuanga und Palawan (Philippinen). Aqua Planta 25(3): 99–107.
Bastmeijer, J.D. & J. Bogner 1999. Dr. H.C.D. de Wit (1909–1999). Aqua Planta 24(2): 65–67.
Bastmeijer, J.D. & N. Jacobsen 2007. Cryptocoryne bangkaensis Bastmeijer, ein neuer Name für eine gut bekannte Cryptocoryne von Sumatra (Indonesien). Aqua Planta 32: 44– 55.
Bastmeijer, J.D. & N. Jacobsen 2020. Artificial hybrids in Lagenandra (Araceae). Aroideana 43(3–4): 59–96.
Bastmeijer, J.D. & N. Jacobsen 2020. Lagenandra ‘Cora Bastmeijer’, an artificial hybrid between the Indian L. meeboldii and the Sri Lankan L. thwaitesii (Araceae). Aroideana 43(3–4): 54–58.
Bastmeijer, J.D. & P. van Wijngaarden 1999. Cryptocoryne coronata Bastmeijer et van Wijngaarden spec. nov. (Araceae), eine neue Art von den Philippinen. Aqua Planta 24(1): 23–28.
Bastmeijer, J.D. & P. van Wijngaarden 1999. Cryptocoryne coronata Bastmeijer et van Wijngaarden spec. nov. (Araceae), eine neue Art von den Philippinen. Aquarium Moscow 2001(5): 26–28.
Bastmeijer, J.D. & R. Kiew 2001. A New Hybrid (Araceae) from the Bukit Timah Nature Reserve, Singapore. Garden's Bulletin Singapore 53: 9–17.
Bastmeijer, J.D. & R. Kiew 2001. Eine neue Cryptocoryne-Art (Araceae) aus dem Bukit Timah Reservat von Singapore. Aqua Planta 26(4): 172–179.
Bastmeijer, J.D. & R. Kiew 2002. Cryptocoryne timahensis. Aquarium Moscow 2002(2): 26–30.
Bastmeijer, J.D. & W. Leenen 1983. Cryptocoryne zewaldiae. Het Aquarium 53(11): 276–279.
Bastmeijer, J.D., 1984. Zeldzame Cryptocorynen (2). Het Aquarium 54(9): 236–239.
Bastmeijer, J. D., 1989. Cryptocoryne scurrilis De Wit. Aqua Planta 14(1): 1, 3–5.
Bastmeijer, J.D., C. Christensen & N. Jacobsen 1984. Cryptocoryne alba und ihre Variationsbreite. Aqua Planta 9(1): 18–22.
Bastmeijer, J.D., H. Budianto, I.B. Ipor, M. Ørgaard, M. & N. Jacobsen 2016. Cryptocoryne wongsoi (Araceae), a new species from Sumatera, Indonesia. Aroideana 39(2):4–14.
Bastmeijer, J.D., H. Kishi, N. Takahashi, S. Wongso & N. Jacobsen 2013. A new variety of Cryptocoryne ferruginea Engl. from Sekadau, West Kalimantan province, Indonesia. The Aquatic Gardener 26(4): 33–38.
Bastmeijer, J.D., H. Kishi, N. Takahashi, S. Wongso & N. Jacobsen 2013. Eine neue Varietät der Cryptocoryne ferruginea Engl. von Sekadau, West Kalimantan, Indonesien. Aqua Planta 38(3): 84–93.
Bastmeijer, J.D., K. Nakamoto & N. Jacobsen 2014. Cryptocoryne matakensis (Araceae), eine neue Art von den Anambas-Inseln (Indonesien). Aqua Planta 39(2): 41, 64–71.
Bastmeijer, J.D., P. Babics & C. Kettner 2012. Eine neue Cryptocoryne-Art aus Sri Lanka (Ceylon). Aqua Planta 37(2): 50–59.
Bastmeijer, J.D., T. Idei, N. Jacobsen, A.M. Ramsdal & D. Sookchaloem 2010. Notes on Cryptocoryne (Araceae) of Thailand, including a new species from Loei Province. Thai Forest Bulletin (Botany) 38: 179–183.
Bastmeijer, J.D. 1979. Cryptocoryne. Blijdorp geluiden 27(2): 4–5.
Bastmeijer, J.D. 1979. Cryptocoryne pontederiifolia. Info ZAG Wasserpflanzen 9(3): 3–4.
Bastmeijer, J.D. 1979. Cryptocoryne pontederiifolia. WAP-krant 79/1: 7–8.
Bastmeijer, J.D. 1981. Naamgeving in Cryptocoryne van Sri Lanka. Meded. WAP 1: 23–28.
Bastmeijer, J.D. 1982. Cryptocoryne van Sumatra. Meded. WAP 2: 1–12.
Bastmeijer, J.D. 1984. Zeldzame Cryptocorynen. Het Aquarium 54(7–8): 198–201.
Bastmeijer, J.D. 1986. Cryptocoryne amicorum De Wit et Jacobsen. Aqua Planta 11(2): 51–54.
Bastmeijer, J.D. 1986. Cryptocoryne amicorum De Wit et Jacobsen. DATZ 39(10): 471–473.
Bastmeijer, J.D. 1986. Prof. dr. de Wit und prof. dr. N.Jacobsen. Ein Portrait. Aqua Planta 11(2): 55.
Bastmeijer, J.D. 1987. Besprekung van: A. de Graaf & J.C. Arends – The occurence of Cryptocoryne and Lagenandra (Araceae) on Sri Lanka. Meded. WAP 8: 27–28.
Bastmeijer, J.D. 1989. Zum 80. Geburtstag von Professor Dr. H.C.D. de Wit. Aqua Planta 14(4): 136–138.
Bastmeijer, J.D. 1991. Cryptocoryne spiralis. Het Aquarium 61(9): 208–211.
Bastmeijer, J.D. 1992. Cryptocoryne spiralis (Retzius) Fischer ex Wydler. Aqua Planta 17(3): 91–95.
Bastmeijer, J.D. 1993. Das Pflanzenportrat: Cryptocoryne fusca De Wit. Aqua Planta 18(3): 108–113.
Bastmeijer, J.D. 2000. Looking for Cryptocoryne aponogetifolia in the Philippines. Planted Aquaria 2: 5–11.
Bastmeijer, J.D. 2001. Cryptocorynes from Sri Lanka – An Album. Planted Aquaria 5: 6–21.
Bastmeijer, J.D. 2002. Cryptocoryne yujii Bastmeijer (Araceae), eine neue Art aus Sarawak. Aqua Planta 27(4): 145–146.
Bastmeijer, J.D. 2009. Professor H.C.D. de Wit (1909–1999). Het Aquarium 79(11): 26–28.
Bastmeijer, J.D. und Vorstand der Aqua-Planta 1998. Harry van Bruggen wurde 70 Jahre alt. Aqua Planta 23(1): 32.
Bastmeijer J.D. 2022. The Crypts pages. https://crypts.home.xs4all.nl/Cryptocoryne/index. html Accessed March 23, 2022.
Bogner, J. & J.D. Bastmeijer 2001. In Memoriam – H.C.D. de Wit (1909–1999). Aroideana Vol 24: 3–5.
Bruggen, H.W.E. van & J.D. Bastmeijer 1995. Cryptocoryne pontederiifolia Schott (1863). DATZ 48(5): 302–303.
Budianto, H. & J.D. Bastmeijer 2004. Eine neue Cryptocoryne-Art (Araceae) aus Kalimantan (Indonesien). Aqua Planta 29(4): 124–130.
Idei, T., J.D. Bastmeijer & N. Jacobsen 2010. Geschichten vom Mekong: Zwei neuen Cryptocorynen (Araceae). Aqua Planta 35(4): 139–146.
Idei, T., J.D. Bastmeijer & N. Jacobsen 2017. Stories from the Mekong, part 2: The Cryptocoryne (Araceae) habitats in the Chiang Khan district, Loei province, Thailand. Thai Forest Bulletin (Botany) 45(1): 58–78. DOI: https://doi.org/10.20531/tfb.2017.45.1.10
Ipor, I.B., C.S. Tawan, S. Wongso, N. Jacobsen, J.D. Bastmeijer & H. Budianto 2016. Diversity and Characteristics of Cryptocoryne (Araceae) Species of Peat Swamp Ecosystem in Borneo. 15th International Peat Congress 2016. Sarawak. p. 712.
Jacobsen, J.D. Bastmeijer & M. Ørgaard 2018. The opening twist (ptyxis) of the spathes of Lagenandra and Cryptocoryne (Araceae). Aroideana 41(2–3): 201–217.
Jacobsen, N, C.B.A. Lange, J.D. Bastmeijer, H. Budianto, T. Idei, I.B. Ipor, A.S. Othman, D. Sookchaloem, S. Wongso & M. Ørgaard 2009. Elements of the evolution in the genus Cryptocoryne (Araceae). I: Monocots IV: Abstract p. 32.
Jacobsen, N. & J.D. Bastmeijer 2014. On Cryptocoryne cordata var. siamensis. The Aquatic Gardener 27(2): 28–39.
Jacobsen, N., C.A. Lange, J.D. Bastmeijer, H. Budianto, T. Idei, I.B. Ipor, A.S. Othman, D. Sookchaloem, S. Wongso & M. Ørgaard 2009. Variation and the evolution in the genus Cryptocoryne (Araceae) or Are species – of Cryptocoryne – natural evolutionary units? Xth International Aroid Conference, Nancy Botanical Garden, France, 8–10 July 2009. Abstracts: Lecture, p. 9.
Jacobsen, N., J.D. Bastmeijer & Y. Sasaki 2002. Cryptocoryne ×purpurea Ridley nothovar. borneoensis N. Jacobsen, Bastmeijer & Y. Sasaki (Araceae), eine neue Hybridvarietät aus Kalimantan. Aqua Planta 27(4): 152–154.
Jacobsen, N., J.D. Bastmeijer, A.S. Othman, D. Sookchaloem & M. Ørgaard 2019. Artificial hybrids in Cryptocoryne (Araceae) 2: Hybridization between species of the Malay Peninsula. Aroideana 42(1): 107–137.
Jacobsen, N., J.D. Bastmeijer, A. Waser, S. Wongso & M. Ørgaard 2019. Artificial hybrids in Cryptocoryne (Araceae) 5: Hybridization with species from Sumatera, Indonesia. Aroideana 42(2–3): 119–138.
Jacobsen, N., J.D. Bastmeijer, B. Bongcheewin, T. Idei, D. Sookchaloem & M. Ørgaard 2015. A new variety of Cryptocoryne crispatula Engl. (Araceae) from Thailand. Thai Forest Bulletin (Botany) 43: 104–110.
Jacobsen, N., J.D. Bastmeijer, C. Christensen, T. Idei, C.A. Lange, J. Orabi, D. Sookchaloem, F. Toneato &. M. Oergaard 2015. The use of AFLP markers to elucidate relationships within Cryptocoryne (Araceae). Aroideana 38E (1): 186–193.
Jacobsen, N., J.D. Bastmeijer, C. Christensen, T. Idei, J. Orabi, D. Sookchaloem, F. Toneato & M. Oergaard 2013. The use of AFLP markers to elucidate relationships within Cryptocoryne (Araceae). The XIth International Aroid Conference, 11.–13. December 2013, Hanoi. Poster abstract, P 4: 31–32. http://crypts.home.xs4all.nl/Cryptocoryne/ Jacobsen2013posterM.jpg.
Jacobsen, N., J.D. Bastmeijer, C. Christesen, T. Idei, C.A. Lange, J. Orabi, D. Sookchaloem, F. Toneato & M. Ørgaard 2017. Cryptocoryne crispatula (Araceae) in Thailand seen with the help of AFLP glasses. 17th Flora of Thailand Conference, 21–25 August 2017, Krabi. E-Poster: 59, p. 143.
Jacobsen, N., J.D. Bastmeijer, H.B. Ganapathy, K.N.A. Mangsor, M. Mansor, A.S. Othman, S.N.A. Rahman, R. Rusly & J. Siow 2013/2015. A new calcicolous variety of Cryptocoryne nurii Furtado (Araceae) from Pahang, Peninsular Malaysia. Malayan Nature Journal 2013, 65(4): 230–239 [published February 22, 2015].
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Jacobsen, N., J.D. Bastmeijer, H. Ganapthy, I.B. Ipor, K.R. Munk, A.S. Othman, R. Rosazlina, J. Siow, T. Komala & M. Ørgaard 2020. Cryptocoryne hybrids (Araceae) 3: Hybrids between Cryptocoryne cordata and Cryptocoryne nurii from southern Peninsular Malaysia. Aroideana 43(1–2): 255–284.
Jacobsen, N., J.D. Bastmeijer, I.B. Ipor, K.R. Munk, S. Wongso & M. Ørgaard 2016. Cryptocoryne ×batangkayanensis (Araceae) und Bemerkungen zu einigen anderen Hybriden. Aqua Planta 41(2): 54–66.
Jacobsen, N., J.D. Bastmeijer, I.B. Ipor, K.R. Munk, S. Wongso & M. Ørgaard 2016. Cryptocoryne ×batangkayanensis and notes on some other hybrids. The Aquatic Gardener 29(4): 37–45.
Jacobsen, N., J.D. Bastmeijer, J. Bogner, H. Budianto, H.B. Ganapathy, T. Idei, I.B. Ipor, T. Komala, A.S. Othman, R. Rosazlina, J. Siow, S. Wongso & M. Ørgaard 2016. Hybrids
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Jacobsen, N., J.D. Bastmeijer, K.R. Jensen, A.S. Othman & M. Ørgaard 2020. Cryptocoryne hybrids (Araceae) 2: Two Cryptocoryne hybrids from southern Peninsular Malaysia. Aroideana 43(1–2): 240–254.
Jacobsen, N., J.D. Bastmeijer, P.J. Edwards, R.J. Johns, N. Takahashi, & S. Wongso 2014. A new variety of Cryptocoryne versteegii (Araceae) from Irian Jaya Tengah, Indonesia. Willdenowia 44(3): 385–391.
Jacobsen, N., J.D. Bastmeijer, S. Wongso & M. Ørgaard 2019. Lagenandra keralensis und L. meeboldii. Aqua Planta 41(3): 84–91.
Jacobsen, N., J.D. Bastmeijer, S. Wongso, M. Ørgaard 2016. New Guinea – Rätsel um Cryptocoryne versteegii und Cryptocoryne dewitii. Aqua Planta 41(4): 130–141.
Jacobsen, N., J.D. Bastmeijer, T. Idei, I.B. Ipor, S. Wongso & M. Ørgaard 2019. Artificial hybrids in Cryptocoryne (Araceae) 3. Hybridization between species from Borneo. Aroideana 42(2–3): 57–90.
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Wongso, S., I.B. Ipor, C.S. Tawan, H. Budianto, J.D. Bastmeijer, & N. Jacobsen 2016. Cryptocoryne aura (Araceae), a new species from West Kalimantan, Indonesia. Willdenowia 46(2): 275–282. https://bioone.org/journals/willdenowia/volume-46/issue-2/ wi.46.46209/Cryptocoryne-aura-Araceae-a-new-species-from-West-Kalimantan-Indonesia/10.3372/wi.46.46209.full
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Wongso, S., J.D. Bastmeijer, Hendrik, K.R. Jensen, H. Kishi, M. Ørgaard, N. Takahashi & N. Jacobsen 2020. Cryptocoryne-hybriden (Araceae): Cryptocoryne ×ikezewaldiae und C. ×agusii, zwei neue Hybriden aus West-Kalimantan, Indonesien. Aqua Planta 45(2): 44–57.
Wongso, S., J.D. Bastmeijer, T. Idei, K.R. Jensen, M. Ørgaard & N. Jacobsen 2020. Cryptocoryne hybrids (Araceae) 4: A Cryptocoryne hybrid from the Meratus mountains, South Kalimantan, Indonesia. Aroideana 43(1–2): 285–298.
Cryptocoryne ×agusii N.Takahashi (C. ferruginea var. sekadauensis × C. fusca)
In Wongso, S., J.D. Bastmeijer, Hendrik, K.R. Jensen, H. Kishi, M. Ørgaard, N. Takahashi & N. Jacobsen (2020). Cryptocoryne-hybriden (Araceae): Cryptocoryne ×ikezewaldiae und C. × agusii, zwei neue Hybriden aus West-Kalimantan, Indonesien. Aqua Planta 45(2): 44–57.
Cryptocoryne ×ardyi Wongso (C. cordata var. wellyi × C. scurrilis)
In Wongso, S., N.P.S. Asih, J.D. Bastmeijer, W. Reichert, K.R. Jensen, M. Ørgaard & N. Jacobsen (2019). Four new Cryptocoryne (Araceae) taxa from Sumatera, Indonesia: a new variety and three interspecific natural hybrids. Taiwania 64(3): 326–338. https:// taiwania.ntu.edu.tw/pdf/tai.2019.64.326.pdf
Cryptocoryne bastmeijeri Wongso
In Wongso, S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N.
Jacobsen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo.
Willdenowia 47: 325–339. https://doi.org/10.3372/wi.47.47314
Cryptocoryne ciliata (Roxb.) Schott var. bogneri N.Jacobsen
In Jacobsen, N., J.D. Bastmeijer, K.R. Jensen & M. Ørgaard (2018). A new tetraploid variety of Cryptocoryne ciliata (Araceae) from Sarawak. Willdenowia 48: 425–431. https:// doi.org/10.3372/wi.48.48312
Cryptocoryne cordata Griff. var. wellyi Wongso
In Wongso, S., N.P.S. Asih, J.D. Bastmeijer, W. Reichert, K.R. Jensen, M. Ørgaard & N. Jacobsen (2019). Four new Cryptocoryne (Araceae) taxa from Sumatera, Indonesia: a new variety and three interspecific natural hybrids. Taiwania 64(3): 326–338. https:// taiwania.ntu.edu.tw/pdf/tai.2019.64.326.pdf
Cryptocoryne crispatula Engl. var. albida (Parker) N.Jacobsen, Maneean. & T.Idei
In Idei, T., S. Maneeanakekul & N. Jacobsen (2022). Stories from the Mekong, part 3. Cryptocoryne (Araceae) habitats in the Kok River, Chiang Rai Province, Northern Thailand. Aroideana 45(1): 281–295.
Cryptocoryne ×decus-silvae De Wit, emend. N. Jacobsen et al.
In Jacobsen, N., J.D. Bastmeijer, H. Ganapthy, I.B. Ipor, K.R. Munk, A.S. Othman, R. Rosazlina, J. Siow, T. Komala & M. Ørgaard (2020). Cryptocoryne hybrids (Araceae) 3: Hybrids between Cryptocoryne cordata and Cryptocoryne nurii from southern Peninsular Malaysia. Aroideana 43(1 & 2): 255–284.
Cryptocoryne erwinii Wongso & Ipor
In Wongso S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N. Jacob-
sen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo. Willdenowia 47: 325–339. https://doi.org/10.3372/wi.47.47314
Cryptocoryne ×griffithiioides N.Jacobsen (C. griffithii × C. nurii var. nurii)
In Jacobsen, N., J.D. Bastmeijer, K.R. Jensen, A.S. Othman & M. Ørgaard (2020). Cryptocoryne hybrids (Araceae) 2: Two Cryptocoryne hybrids from southern Peninsular Malaysia. Aroideana 43(1–2): 240–254.
Cryptocoryne ×hendrae Wongso (C. hudoroi × C. striolata)
In Wongso S., J.D. Bastmeijer, T. Idei, K.R. Jensen, M. Ørgaard & N. Jacobsen (2020). Cryptocoryne hybrids (Araceae) 4: A Cryptocoryne hybrid from the Meratus mountains, South Kalimantan, Indonesia. Aroideana 43(1 & 2): 285–298.
Cryptocoryne ×ikezewaldiae Bastm. (C. cordata var. grabowskii × C. pallidinervia)
In Wongso, S., J.D. Bastmeijer, Hendrik, K.R. Jensen, H. Kishi, M. Ørgaard, N. Takahashi & N. Jacobsen (2020). Cryptocoryne-hybriden (Araceae): Cryptocoryne × ikezewaldiae und C. × agusii, zwei neue Hybriden aus West-Kalimantan, Indonesien. Aqua Planta 45(2): 44–57.
Cryptocoryne isae Wongso
In Wongso, S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N. Jacobsen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo. Willdenowia 47: 325–339. https://doi.org/10.3372/wi.47.47314
Cryptocoryne ×jambiensis Bastm. (C. bangkaensis × C. nurii var. nurii)
In Wongso, S., N.P.S. Asih, J.D. Bastmeijer, W. Reichert, K.R. Jensen, M. Ørgaard & N. Jacobsen (2019). Four new Cryptocoryne (Araceae) taxa from Sumatera, Indonesia: a new variety and three interspecific natural hybrids. Taiwania 64(3): 326–338. https:// taiwania.ntu.edu.tw/pdf/tai.2019.64.326.pdf
Cryptocoryne joshanii Naive & Villanueva
Naive, M.A.K. & R.J.T. Villanueva (2018). Cryptocoryne joshanii (Araceae), a new species serendipitously discovered in Sulu archipelago, Philippines. Taiwania 63(3): 248–250. https://taiwania.ntu.edu.tw/pdf/tai.2018.63.248.pdf
Cryptocoryne ×nakamotoi Bastm. (C. uenoi × C. verrucosa)
In Asih, N.P.S., S. Wongso, Hendrik, J.D. Bastmeijer, S. Reitel, K.R. Jensen, M. Ørgaard & N. Jacobsen (2022). New Cryptocoryne (Araceae) from West Kalimantan, Indonesia: a new species and a new interspecific natural hybrid. Aroideana 45(1): 296–312.
Cryptocoryne regina Wongso & Ipor
In Wongso, S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N. Jacobsen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo.Willdenowia 47: 325–339. https://doi.org/10.3372/wi.47.47314
Cryptocoryne sahalii Wongso & Ipor
In Wongso S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N. Jacob-
sen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo.Willdenowia 47: 325-339. https://doi.org/10.3372/wi.47.47314
Cryptocoryne ×schulzeioides N.Jacobsen (C. griffithii × C. schulzei)
In Jacobsen, N., J.D. Bastmeijer, K.R. Jensen, A.S. Othman & M. Ørgaard (2020). Cryptocoryne hybrids (Araceae) 2: Two Cryptocoryne hybrids from southern Peninsular Malaysia. Aroideana 43(1–2): 240–254.
Cryptocoryne tirtadinatae Wongso
In Wongso, S., Hendrik, K.R. Jensen, M. Ørgaard & N. Jacobsen (2020). A new Cryptocoryne species (Araceae) from the Schwaner mountains, West Kalimantan, Indonesia. Nordic Journal of Botany 38(4): e02716, p. 1–5 (2020). https://doi.org/10.1111/njb.02716.
Cryptocoryne verrucosa Wongso & Asih
In Asih, N.P.S., S. Wongso, Hendrik, J.D. Bastmeijer, S. Reitel, K.R. Jensen, M. Ørgaard & N. Jacobsen (2022). New Cryptocoryne (Araceae) from West Kalimantan, Indonesia: a new species and a new interspecific natural hybrid. Aroideana 45 (1): 296-312.
Cryptocoryne yujii Bastm. var. hendrikii Wongso
In Wongso, S., J.D. Bastmeijer, H. Budianto, I.B. Ipor, K.R. Munk, M. Ørgaard & N. Jacobsen (2017). Six new Cryptocoryne taxa (Araceae) from Kalimantan, Borneo. Willdenowia 47: 325–339. https://doi.org/10.3372/wi.47.47314
Cryptocoryne ×zukalii Rataj nothovar. sumateraensis W.Reichert (C. cordata var. diderici × C. minima)
In Wongso, S., N.P.S. Asih, J.D. Bastmeijer, W. Reichert, K.R. Jensen, M. Ørgaard & N. Jacobsen (2019). Four new Cryptocoryne (Araceae) taxa from Sumatera, Indonesia: a new variety and three interspecific natural hybrids. Taiwania 64(3): 326–338. https://taiwania.ntu.edu.tw/pdf/tai.2019.64.326.pdf
