Founded in 1991 and published by the Indian Association for Angiosperm Taxonomy (IAAT), Rheedea is an international peer-reviewed journal with four online and two print issues per year. The online issues will be published in March, June, September and December while the printed issues will be published in June and December. Rheedea is a peer-reviewed journal named after the renowned Dutch botanist Hendrik van Rheede, known for his seminal work Hortus Malabaricus. ISSN: 2582-2438 (Online edition) ISSN: 0971-2313 (Print edition)
Journal of the Indian Association for Angiosperm Taxonomy
Hyphaene dichotoma (Arecaceae): an addition to floristic diversity of eastern India
Section: New Reports Keywords: Botanical exploration, Branching palm, Coastal ecology, Dichotomous,, Palmyra palm Hyphaene dichotoma (D.White bis ex Nimmo) Furtado (Arecaceae) is reported here as an addition to floristic diversity of eastern India, based on collections from forest of Bankura district, West Bengal. This species has previously been reported from Diu, Goa, Gujrat and Maharashtra. This study aims for a detailed description along with photographs and geographical latitudinal and longitudinal data that supports the addition to the flora of the Bankura district, West Bengal, India.
Copyright (c) 2026 Rheedea https://creativecommons.org/licenses/by-nc-nd/4.0
Homalomena randii, a new species of Araceae from West Kalimantan, Borneo
Section: New Taxa Subjects: Araceae, Hanneae Complex, Malesia, Philodendreae, Sambas Homalomena randii is described and illustrated here as a new species of Araceae from West Kalimantan, Indonesia. The new species is assigned to the Cyrtocladon Supergroup based on a combination of morphological characters, including typically hastate leaf blades with pronounced posterior lobes; staminate flowers consisting of (3–)4(–5) truncate stamens, each surmounted by a large, flat, cream-colored connective; and the presence of conspicuous resin droplets secreted between the staminate flowers. This discovery underscores the strong potential for further discoveries of Homalomena species in underexplored regions of Indonesian Borneo, highlighting the continuing importance of botanical exploration in the area.
Lectotypification of three names and a new synonymy in Alseodaphne (Lauraceae) of India
Section: Typification/Combinations Subjects: Typification, Isolectotype, Peninsular India, Syntype Lectotypes are designated here for Alseodaphne semecarpifolia Nees var. angustifolia Meisn., A. semecarpifolia Nees var. macrocarpa Hook.f. and A. semecarpifolia Nees var. parvifolia Wight ex Hook.f. based on critical examination of the protologues and original materials. A. semecarpifolia Nees var. macrocarpa is reduced to the synonymy of Alseodaphne semecarpifolia Nees var. angustifolia, as the diagnostic characters used to distinguish the former fall within the morphological variation observed in the latter.
A conspectus of the genus Ipomoea (Convolvulaceae) in India
Section: Monographs/Revisions Keywords: Diversity, Morning glory, Tropical Asia, Moon flowers Subjects: Taxonomy, Conspectus, Convolvulaceae, India The family Convolvulaceae are one of the dominant families of flowering plants in India, and the genus Ipomoea L. is the largest and most diverse within it, both globally and in India. Ipomoea displays remarkable diversity in shape, size, and flower colour, making it a subject of interest for horticulturists, naturalists, and researchers worldwide. A comprehensive account of Ipomoea in India was prepared using data collected through extensive field surveys across diverse phytogeographical regions since June 2013. The present study documents 52 taxa (51 species and one infraspecific taxon) of Ipomoea in India. A key for the identification of species is provided. For each species, detailed morphological descriptions, illustrations and notes on habitat, distribution, diagnostic characters and present status are provided. The occurrence of Ipomoea lacunosa L. and Ipomoea vagans Baker in India is also discussed.
The Taxonomic updates on Parsonsia (Apocynaceae) from Vietnam: a new record and lectotypification
Section: Articles Keywords: Gentianales, Kim Hy, Plant diversity, Taxonomy, Thai Nguyen Subjects: Parsonsia, Apocynaceae, New Report Parsonsia goniostemon Hand.-Mazz., previously known only from China, is newly recorded for the flora of Vietnam based on specimens collected from Kim Hy Nature Reserve in Thai Nguyen Province. This species is morphologically allied to P. alboflavescens (Dennst.) Mabb. but can be distinguished by its shorter petioles and stamens inserted at the corolla throat. A detailed description, photographic illustrations, and comparisons with the morphologically allied species are provided. Notes on its habitat, ecology, distribution, and provisional conservation status in Vietnam are also included. In addition, a lectotype is designated for the name P. goniostemon to stabilize its nomenclature.
Gentianales, Kim Hy, Plant diversity, Taxonomy, Thai Nguyen
First documented reports of the Australian Atriplex suberecta (Amaranthaceae s.l., Chenopodioideae) from Tunisia, a well-established weed in North Africa
Section: New Reports Keywords: Alien Atriplex, Chorology, New records, Xenophytes Subjects: Alien Atriplex, New records, North Africa, Tunisia, Xenophytes Atriplex suberecta I.Verd. (Amaranthaceae s.l., Chenopodioideae) is native to southern Australia and alien but naturalized in warm temperate and subtropical regions of the world. In North Africa, the plant has been long established in Morocco, with recent findings in Algeria. Here we report numerous documented findings of A. suberecta from the Mediterranean part of the country, with a detailed morphological description, ecological characteristics, and composition of the alien Atriplex in Tunisia.
Notes on Isachne veldkampii (Poaceae) and reduction of I. bhatii as conspecific
Section: Articles Keywords: Endemism, Grass, Isachne veldkampii, South India, Synonym, Variations. Subjects: Endemism, Grass, Isachne veldkampii, South India, Synonym, Variations. The recently described species Isachne bhatii P.Biju, Josekutty & Augustine is treated as conspecific to I. veldkampii K.G.Bhat & Nagendran. A detailed description, notes on habitat, distribution, conservation status, and photographs are provided. Although the species was previously considered Critically Endangered, the present study reveals a broader distribution than was previously documented.
Endemism, Grass, Isachne veldkampii, South India, Synonym, Variations.
The Pioneering Works of Carl Linnaeus (1707-1778)
Section: Biography Keywords: Test The multi-faceted contributions of Linnaeus are briefly reviewed. From the early times as a student when his original ideas on plants and their sexuality blossomed to artificially classify for ease to identify, understand and to refine, as interactions with great men of science of the day continued, crystallizing the concepts and putting across for wide appreciation, Linnaeus impeccably edited his thoughts, as nobody could make it. His concepts on species, genera and classification of the world flora were uniquely original, which helped the later generations to work on and perfect it.
Studies on Reproductive aspects of Willisia selaginoides (Podostemaceae), an endemic species from Kerala
Section: Articles Keywords: Endemic, germination, Podostemoideae, self-pollination, thallus The present study deals with some aspects of reproductive biology of an endemic and endangered aquatic angiosperm, Willisia selaginoides (Bedd.) Warm. ex Willis (Podostemaceae) restricted to the Western Ghats of India. Due to its occurrence in the challenging habitats, there is limited information available on its reproductive biology. Willisia possesses a small tuft of shoots with triangular thick scales and terminal flowers. The horizontal thallus arising after seed germination is considered as primary shoot and the vertical shoots arising on the dorsal surface of the thallus are considered as secondary shoots. The gummy substance exudes from the lower elongated surface cells (rhizoids) of the shoots and holdfast help in firm attachment to the shoots to rocks in fast flowing water. The flower is enclosed in spathella and represented by a pistil with bilobed stigma and a pair of dithecous anthers. Initiation of flower buds and subsequent development occurs in submerged conditions but flowers open only after the water level lowers down after monsoon. Pollination occurs when the flowers are just exposed to air after lowering of water level at the air-water interface. Co-occurrence of stigma receptivity with anther dehiscence and the close proximity of two organs seem to promote self -pollination. The pollen:ovule ratio (32:1) and ovule:seed ratio (6:5) suggest that even after relatively low pollen:ovule ratio, chances of high seed set occur. It clearly indicates the best possibility of selfpollination.
Evolution of macro and micromorphology of Eriocaulon (Eriocaulaceae) and its relation with the aquatic environment
Section: Articles Keywords: Poales, Pipeworts, Taxonomy, Anatomy, Aquatic habitat, Evolution Eriocaulon L. is a pantropical genus comprising approximately 495 species. Previous taxonomic studies have proposed infrageneric classifications based on selected morphological characters; however, molecular phylogenetic analyses have shown that most of these classifications are paraphyletic. A recent multivariate analysis of anatomical data identified two major groups within the genus: one composed of amphibious species and the other of aquatic species. In this context, the present study aims to test the hypothesis that these groups correspond to distinct evolutionary clades by conducting a cladistic analysis of Eriocaulon based on morphological data. Our analysis included 65 species of Eriocaulon and seven outgroup species, using a dataset of 89 macro- and micromorphological characters. Parsimony analyses conducted in TNT recovered 24 equally parsimonious trees. In all analyses, Eriocaulon was resolved into two main clades. One clade comprises amphibious species from Africa and the Americas and shares plesiomorphic character states with Mesanthemum Körn., including palisade epidermal cells, stomatal chambers, and numerous vascular bundles in the leaf. The other clade, comprising aquatic species distributed across all continents, is characterized by derived character states, including a reduced number of vascular bundles, isodiametric epidermal cells, and the loss of stomatal chambers. These results suggest that the evolutionary history of Eriocaulon is closely tied to anatomical adaptations that facilitate colonization of aquatic environments.
A synopsis of genus Ammannia L. (Lythraceae) in India
Section: Articles Keywords: Ammannia, macrophyte, Myrtales, India, taxonomy The genus Ammannia L. (Lythraceae) in India is revised and a taxonomic synopsis is presented. In this study, nine species are recognized. Ammania nagpurensis T.Mathew and M.P.Nayar have been synonymized under A. multiflora. A key to the species, along with brief descriptions, phenology, habitat preference, distribution, and conservation status are provided. Additionally, detailed taxonomic and nomenclatural notes are presented to aid in species identification and to reconcile ambiguities in taxonomic treatments.
Structural Diversity of Flowers and Pollination Ecology in Podostemaceae
Section: Articles Keywords: Aquatic angiosperms, evolution, floral biology, perianth, spathella, pollination diversity Podostemaceae, or “river-weeds,” are a diverse family of freshwater angiosperms adapted to fast-flowing tropical and subtropical rivers. With over 300 species, they exhibit remarkable morphological variation across regions, especially between New World and Old-World taxa. Their life-cycle is tightly synchronized with seasonal water levels, with flowering and seed production occurring as waters recede. These plants rely solely on sexual reproduction, making pollination a key evolutionary driver for diversification. Different pollination strategies, melittophily, anemophily, and self-pollination have been reported within the family. However, integration of floral morphology and pollination biology remains limited. Thus, an overview of reproductive characters in Podostemaceae is presented, focussing on characters that are useful in understanding the pollination strategies and functional floral morphology in the family. This review synthesizes current knowledge to explore how pollination systems and floral traits have shaped the evolutionary trajectory of Podostemaceae.
Heteranthera reniformis (Pontederiaceae): A new addition to the Asian continent from India
Section: New Reports Keywords: Heteranthera reniformis, new addition, India, Asia Heteranthera reniformis (Pontederiaceae) is recently collected from the Vyenkatapur village, Sironcha taluka, Gadchiroli district, Maharashtra. It is reported here as a new record for the continent of Asia. A comprehensive taxonomic account is provided with description, photographs and distribution to facilitate easy identification of the species in the field.
Taxonomic revision of genus Potamogeton (Potamogetonaceae) in Kashmir Himalaya, India
Section: Monographs/Revisions Keywords: Potamogeton species, taxonomy, morphology, first report, Kashmir Himalaya Potamogeton L. (Potamogetonaceae) is one of the diverse genera of aquatic plants. Owing to its reduced floral morphology and high phenotypic plasticity, the genus has remained taxonomically challenging. This study presents taxonomic revision of Potamogeton in Kashmir Himalaya, based on comprehensive field collections made over the last decade (2010–2020), supplemented with investigations on earlier herbarium collections. During the present study, aquatic habitats across the Kashmir Himalaya were surveyed, and 15 study sites were selected for detailed sampling spanning an elevation gradient of 1595 to 2180 m asl. The study records 12 Potamogeton species in the region, with detailed morphological characterization, identification key, line drawings, and photographs. The three species, namely, P. amblyophyllus C.A. Meyer, P. berchtoldii Fieber, and P. trichoides Cham. & Schltdl. are the first-time reports from this region, while the latter two species are new distribution records for India as well. Overall, the study brings clarity to the taxonomy of Potamogeton - the largest aquatic genus in Kashmir Himalaya, and the findings have practical implications in the sustainable management and restoration of aquatic ecosystems in this Himalayan region, with learnings for neighboring regions.
The status and conservation of Malabar River-lily (Crinum malabaricum) (Liliopsida: Amaryllidaceae)
Section: Articles Keywords: Ecology, Conservation, Laterite Hills, Kerala The Malabar river-lily (Crinum malabaricum Lekhak & S.R.Yadav) is endemic to northern Kerala, south-western India, it was described new to science in 2012. It is native to seasonal rivers flowing over laterite at 80-100 m above sea level, in an area of approximately 5 x 10 km in Kannur and Kasaragod Districts. Populations are limited upstream by reaches involving steeper gradients with faster flow and downstream by deeper water over silt. It typically forms dense stands covering the entire channel with leaves forming a dense mat as water levels drop. Population counts suggest that the global population is more than 25,000 individuals. All known populations are abundantly fertile, flowering and setting seed abundantly from early September to late November. C. malabaricum is a major ecosystem architect, providing shelter for fish and invertebrate communities. Overall, known populations of C. malabaricum may be considered stable and relatively secure, although there is potential for local actions to affect all populations. The apparent absence of a mechanism for formal protection of sites supporting C. malabaricum highlights the need for surveys of potentially suitable habitat within the known range of the species, as well as for monitoring of all known populations to identify population trends.
Microecology and floristic diversity of seasonal wetlands of a lateritic plateau of South India
Section: Articles Keywords: Biodiversity, Conservation, Ecology, Ephemeral pools, Laterite flora, Northern Kerala An analysis of the microecology and floristic diversity of the seasonal pools on the Madayippara lateritic plateau, located in Kannur District of Kerala, South India, was conducted. Temporary wetlands of varying sizes are formed during the rainy season, supporting a large number of habitat-specific flowering plants, a greater number of which are endemic, and a few belong to various threat categories. The seasonal pools vary in their size, soil cover and texture, and are subjected to extreme diurnal changes in temperature due to the high surfaceto-volume ratio. They are characterised by high variation in soil temperature and water pH between pools and between seasons, extreme variation of water temperature in different seasons and in different hours of a day, and also hold maximum moisture content with extreme variation in different seasons. The soil type in most of the seasonal pools is sandy loam, and is the richest with respect to soil nutrients. The occurrence of high diversity of carnivorous plants in these nutrient-rich habitats is ascribed to the limitation in nutrient absorption, resulting from factors such as low pH, inundation and low phosphorus levels. Seasonal pools are highly specialised microhabitats active only in the monsoon period to support several specialised species showing a high degree of endemism owing to their characteristic microecology.
Neotypification of the name Diplomeris pulchella (Orchidaceae)
Section: Typification/Combinations Keywords: Diplomeris pulchella, Nomenclature, Typification, Wallich Diplomeris pulchella D.Don (Orchidaceae) was described with an obscure indication of the type, referring only to a Wallich collection from Nepal. Subsequent searches for Wallich specimens from Nepal failed to locate any relevant material. However, a specimen of D. pulchella collected by Wallich from Sylhet, Bangladesh, is preserved at BM. It remains uncertain whether Don mistakenly cited the locality as “Nepalia” instead of Sylhet, or whether the BM specimen does not represent original material. As the BM specimen cannot be confidently confirmed as original material, it is here designated as the neotype.
Diplomeris pulchella, Nomenclature, Typification, Wallich
Typification of Candollean names in the tribe Gnaphalieae (Asteraceae)
Section: Typification/Combinations Keywords: Anaphalis, Helichrysum, Lectotype, Pseudognaphalium Revisionary studies on the tribe Gnaphalieae of Asteraceae (subfam. Asteroideae) in southern India could identify many names attached to different collections at various herbaria, without precise original materials designated as types. Candollean names of Anaphalis notoniana DC., Helichrysum buddleioides DC., and Pseudognaphalium hypoleucum (DC.) Hilliard & B.L.Burtt, have been typified following the latest botanical code.
Anaphalis, Helichrysum, Lectotype, Pseudognaphalium
Taxonomic reassessment of Impatiens verecunda (Balsaminaceae) and its synonymization with I. cordata in the Western Ghats, India
Section: Articles Keywords: Anamalai hills, Devikulam, Idukki, Impatiens anaimudica, Kerala Historical records, such as those by J.D. Hooker and subsequent studies, have noted taxonomic complexities in Impatiens verecunda Hook.f. and its relationship with I. cordata Wight and I. anaimudica C.E.C.Fisch. Field surveys in Devikulam, Kerala, discovered specimens resembling I. verecunda, prompting detailed morphological comparisons with I. cordata and I. anaimudica. The plants exhibited similarities to I. cordata, differing only in habitat-driven traits like short stature and short floral spurs, confirmed the synonymization of I. verecunda under I. cordata. Conversely, I. anaimudica remains distinct due to its lenticelled stems, crimson flowers, and unique spur morphology. Further studies on I. cordata populations revealed variations in life history, habit, flower color, spur length, and floral morphology, influenced by environmental conditions. A revised description of I. cordata is presented to account for these variations and clarify its distinction from closely related taxa like I. elegans Bedd.
Anamalai hills, Devikulam, Idukki, Impatiens anaimudica, Kerala
Physalis cordata (Solanaceae): a new record for India
Section: New Reports Keywords: Physalis, North 24 Parganas district, West Bengal, Invasive species, Native of Americas Physalis cordata Houst. ex Mill. (Solanaceae), a native of North and South America has been collected from North 24-Parganas district of West Bengal, India in 2024 is reported here as an addition to the Flora of India. Morphological description, location map and a photo plate are provided here for its proper recognition.
Physalis, North 24 Parganas district, West Bengal, Invasive species, Native of Americas
A taxonomic revision of the genus Justicia (Acanthaceae) in Peninsular India
Section: Monographs/Revisions Keywords: Conservation Assessment,, Justicieae, Lectotypification, Synonymization A detailed taxonomic account of the genus Justicia L. in Peninsular India is provided, with 18 species recognized. Lectotypifications of six names are carried out. Nine taxa are treated as synonyms: Justicia diffusa var. orbiculata C.B.Clarke of J. diffusa Willd.; J. nilgherrensis (Nees) Wall. ex C.B.Clarke and J. tamilnadensis P.Raja & Soosairaj of J. trinervia Vahl; J. nagpurensis V.A.W.Graham, J. notha C.B.Clarke and J. pathanamthittiensis Remadevi & Binojk. of J. procumbens L.; J. quinqueangularis var. kawalii Annamma & Venu of J. quinqueangularis J.Koenig ex Roxb.; J. salsoloides T.Anderson of J. tranquebariensis L.f. and J. vahlii var. rupicola (J.L.Ellis) Pull., Moulali & Sandhyar. of J. vahliana Schult. Detailed descriptions, photographic images and a key for identifying species in Peninsular India are provided along with data on phenology, distribution and conservation status.
Peter Hamilton Raven (1936–2026): A Global Architect of Biodiversity Conservation and a Friend to Indian Botany
Section: Obituaries Keywords: Peter Hamilton Raven, Obituary No abstract for this article
Dr. Amarjit Singh Soodan: A Renowned Botanist, Taxonomist and A Mentor
Section: Obituaries Keywords: Grass flora, Phytoliths Dr. Amarjit Singh Soodan, one of India’s renowned botanists and a distinguished figure in plant taxonomy and phytolith research, passed away peacefully at his residence in Alpha International City, Daburgi, Amritsar on 21 November 2025. He was 66 years old and is survived by his wife and two children. His departure marks the end of an era for the botanical community of North India, where he inspired generations of students, researchers and colleagues through his scholarship, humility and unwavering commitment to the discipline of botany.
Section: Book Reviews Authored by Natesh S. Illustrations by Sagar Bhowmick. Published by Roli Books, Delhi, India. Hardbound. ISBN: 9789392130342. Pages 256. Price: (INR) 1995.00
Note on taxonomy and typification of Vigna hainiana Babu, Gopinathan & Sharma ( =Phaseolus wightii W. & A.)
Section: Typification/Combinations Vigna hainiana Babu, Gopinathan & Sharma, collected from north-western and eastern parts of India, has been studied. Characters for differentiating this species have been delineated. The type indicated previously for V. hainiana was incorrect; Wall. L. n. 5591 is the lectotype for this species.
Book Review: Know Your Grass Genera Through Hand Lens
Section: Book Reviews -
The Genus Ludwigia (Onagraceae) in India
Section: Articles Keywords: India, Ludwigia, Taxonomy The genus Ludwigia L. consists of seven species and one infraspecific taxon in India, of which L. decurrens forms the first report for India. This revision provides a key to species, descriptions and illustrations along with data on phenology, distribution and notes on ecology.
Solanum cordatum (Solanaceae) – A new record to Southern India
Section: New Reports Keywords: Kolli hills, New record, Solanum cordatum, Southern India While preparing an inventory of flowering plants of the Kolli hills, Namakkal district, Tamil Nadu, Southern India, some specimens of Solanum L. were collected and identified as S. cordatum Forssk. On scrutiny of literature, it is revealed that this species is known only from Gujarat in India and forms a new record to Southern India. Hence, a detailed description, phenology and illustration are provided to facilitate easy identification of the species.
Syzygium claviflorum (Myrtaceae) – A new record for South India
Section: New Reports Keywords: Myrtaceae, New record, South India, Syzygium claviflorum Syzygium claviflorum (Roxb.) Wall. ex A.M. Cowan et Cowan, a Myrtaceous tree species is reported for the first time for South India from Agasthyamalai Biosphere Reserve of the southern Western Ghats. A brief description and illustration of the species are provided herewith for easy identification.
Rediscovery of Pogostemon nilagiricus (Lamiaceae), a steno-endemic and critically endangered aromatic species
Section: Articles Keywords: Aromatic plant, Endemic, Lamiaceae, Nilgiri, Pogostemon Pogostemon nilagiricus Gamble (Lamiaceae) is rediscovered from Nilgiri hills, the type locality, after a gap of 97 years. A detailed description, photograph and note on its taxonomy are provided. Current threat status has also been assessed based on the recent botanical explorations.