Gustavo HassemerFederal University of Mato Grosso do Sul · Três Lagoas Campus
Gustavo Hassemer
Ph.D.
About
142
Publications
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Introduction
My main scientific focus is in plant taxonomy, nomenclature and conservation, especially of herbaceous plants. I'm also active in promoting policies relating to biodiversity conservation, debureaucratisation of international taxonomic research and restoration of funding for actual taxonomic studies. Furthermore, I'm a proponent of the use of decentralised infrastructure, namely blockchain, to make scientific communication more efficient, censorship-resistant and accessible to all.
Additional affiliations
March 2005 - December 2010
November 2018 - October 2019
September 2013 - May 2014
Education
August 2014 - November 2017
August 2011 - August 2013
March 2005 - December 2010
Publications
Publications (142)
The State of Santa Catarina, located in southern Brazil, presents great diversity of topography, landscapes and vegetation types. It also harbors a very rich biodiversity, and many species are exclusive to this territory. As a consequence of the destruction of most of its original vegetation, a considerable part of this biodiversity is threatened....
Plantago is a cosmopolitan genus including over 250 species, concentrated in temperate and high-elevation tropical regions. The taxonomy of Plantago is very difficult, mainly because of its reduced morphology, which features relatively few characters for species classification. Consequently, the infrageneric classification of the genus remains cont...
A molecular investigation of large-leaved Gunnera growing outside in Britain and Ireland was conducted. Two low-copy nuclear CYCLOIDEA-like genes (CYC-like 1 and CYC-like 2) and two chloroplast DNA regions (matK and psbD-trnT) were sequenced for 271 samples of Gunnera. While it was confirmed that genuine G. tinctoria is growing both in cultivation...
A review of the available knowledge for the Tunisian-Algerian endemic Plantago tunetana is proposed in the present work. This narrowly endemic species was hitherto known from Tunisia within a very restricted area. Field surveys of its occurrence during the last few years, within its locus classicus, allow to find only one population in Gouraïa loca...
Arbuscular mycorrhizal fungi (AMF) have evolved associations with roots of 60% plant species, but the net benefit for plants vary broadly from mutualism to parasitism. Yet, we lack a general understanding of the evolutionary and ecological forces driving such variation. To this end, we conducted a comparative phylogenetic experiment with 24 species...
Taxonomy of the South American Portulaca is advancing considerably but many problems and knowledge gaps still remain. As a result of further investigation of the genus, P. ferricola is here proposed as new name to replace, at species rank, the hitherto overlooked P. mucronulata var. microphylla. P. ferricola is a species endemic to ironstone grassl...
Retracing pathways of historical species introductions is fundamental to understanding the factors involved in the successful colonization and spread, centuries after a species’ establishment in an introduced range. Numerous plants have been introduced to regions outside their native ranges both intentionally and accidentally by European voyagers a...
Unequivocal communication of knowledge about organisms requires unequivocal names by which to refer to them. When the same name is used to refer to very distinct groups of organisms, misunderstanding and problems are certain to follow. In this work we discuss the complicated issues linked to the use of the name Stellaria to refer to species of Call...
The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiver-sity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxo-nomic impediment to biodiversity research and conservation planning. The taxonomic impedi...
The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiver-sity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxo-nomic impediment to biodiversity research and conservation planning. The taxonomic impedi...
The tribe Plantagineae (Lamiales) is a group of plants with worldwide distribution, notorious for its complicated taxonomy and still unresolved natural history. We describe the result of a broadly sampled phylogenetic study of tribe. The expanded sampling dataset is based on the trnL-F spacer, rbcL, and ITS2 markers across all three included genera...
In this work, we describe a new species of Ludwigia from southern Brazil. We provide a detailed morphological account, field photographs and a distribution map. We also discuss the morphology and taxonomy of the new species in relation to morphologically similar species and assess its conservation status. Finally, we typify the name L. myrtifolia,...
High-throughput sequencing, when combined with taxonomic expertise, is a powerful tool to refine and advance taxonomic classification, including at the species level. In the present work, a new species, Plantago campestris , is described out of the P. commersoniana species complex, based on phylogenomic and morphological evidence. The main morpholo...
Callitriche is a sub-cosmopolitan plant genus occurring throughout temperate regions of both hemispheres, including the peri-Antarctic islands, with 78 species worldwide. Records of Callitriche include frequent and extensive misidentification due to a combination of factors including a lack of taxonomic and nomenclatural clarification before the mi...
Margyricarpus pinnatus is a poorly understood entity from natural grasslands of South America that it better considered as a species complex. In this work we contribute to the advancement of the taxonomic knowledge of this challenging species complex by describing two new species of Margyricarpus from southern Brazil. We present field photographs,...
In a recently-published work it was demonstrated that the previous circumscription of Erechtites valerianifolius encompassed two distinct species, thus calling for the re-establishment of E. petiolatus. However, in that work it was overlooked that Senecio albiflorus, a replacement name for Cacalia prenanthoides, was published three months before E....
We describe a narrowly endemic new species of Delairea from the highlands of southern Brazil. It is the second species described in this previously monospecific genus that was endemic to Africa, and the first record of a native species of Delairea in the Americas. Delairea aparadensis differs from D. odorata by its deltoid leaves and capitulescence...
A new species of Persicaria, P. humboldtiana, endemic to a narrow area of waterfalls in Corupá, southern Brazil, is described in the present paper. The locus classicus of the new species is well-known for plant endemisms. A complete morphological description, original pictures, a distribution map, and a morphological comparison with the similar Eur...
In this work we present taxonomic notes for the genus Erechtites. More specifically, we present evidence for the re-establishment of E. petiolatus, a species that was hitherto being considered as a synonym of either E. valerianifolius or E. valerianifolius f. prenanthoides. Thus, we raise to six the number of accepted species of Erechtites. We pres...
The attractive colour characteristics of the flowers of the species Impatiens walleriana have been arousing great interest in the food industry, which is looking for potential natural sources of colouring ingredients. In this sense, the present work focused on the chemical and bioactive characterization of pink and orange flowers of I. walleriana....
The urge to organise the world around us is an essential part of human nature. Naming and categorising enable us to store and access information ef ciently. The need to name and categorise extends to the natural world and, in particular, to living organisms. The science underpinning this area of knowledge is called Taxonomy, and is as old as humani...
Plantago robusta is a critically endangered species endemic to Saint Helena Island, a remote British island located in the middle of the South Atlantic Ocean. Despite its already acknowledged considerable importance for biodiversity conservation, the species is notably poorly studied from a systematic point of view. In this work we typify the name...
Plantago australis is considered to be obligately cleistogamous. Here we present evidence based on field work, herbarium collections and literature to show that this species produces both chasmogamous and cleistogamous flowers. We also hypothesise that the species is ambophilic.
In this work we describe Ludwigia humboldtiana, an extremely narrowly endemic new species from a waterfall system in Corupá municipality, Santa Catarina, southern Brazil. This is already the second plant species endemic to the area. The new species is morphologically most similar to L. caparosa, L. elegans, L. multinervia and L. peruviana but diffe...
We present here novelties and notes on Tradescantia from Brazil. More specifically, we describe a narrowly endemic new species from southern Brazil (T. insularis), create a new name at the species rank (T. catharinensis) for T. crassula var. gaudichaudii, discuss the taxonomy of T. schwirkowskiana and T. serrana, and lectotypify T. tenella and pres...
New Guinea is the world’s largest tropical island and has fascinated naturalists for centuries. Home to some of the best-preserved ecosystems on the planet and to intact ecological gradients—from mangroves to tropical alpine grasslands—that are unmatched in the Asia-Pacific region, it is a globally recognized centre of biological and cultural diver...
The tribe Plantagineae (Lamiales) is a group of plants with worldwide distribution, notorious for its complicated taxonomy, still unresolved natural history, and a trend of morphologic reduction and simplification. This tribe includes the plantains (Plantago), the small aquatic Littorella, and the northern Andean shrubs Aragoa. Some Plantago lineag...
https://authorea.com/users/337132/articles/462777-travel-tales-of-a-worldwide-weed-genomic-signatures-reveal-colonial-trade-routes-and-prior-adaptation-are-key-to-the-success-of-plantago-major
The only species of Bergia known from South America, B. arenarioides, was originally described as Merimea arenarioides in 1829 and has been surprisingly neglected in the literature and databases since after the publication of the treatment of the Elatinaceae for Flora brasiliensis in 1872. The species is only known from two gatherings, both from no...
Commelina dielsii is a species notable for being, together with the southern Brazilian C. catharinensis, the only native Commelina from the Americas with yellow petals. The species was up until now only known from the type gathering, made in 1878 in Entre Ríos province, north-eastern Argentina. Because it had not been collected since then, the spec...
Study of the Commelina names published for the Americas and their original materials, in the context of a continental taxonomic revision of the genus, evidenced the need for typifications and synonymisations. In this work, 18 names are lectotypified (Athyrocarpus pseudomonosperma, C. aquatica, C. bravoa, C. diffusa var. cordispatha, C. dubia Redout...
Evidence is presented that the records of Plantago virginica from South Africa and of P. australis from Réunion Island (France) are in fact misidentified specimens of P. tomentosa. These are the first records of P. tomentosa outside South America. The species is native to Argentina, Bolivia, southern Brazil, southern Paraguay, southern Peru and Uru...
http://floradobrasil.jbrj.gov.br/reflora/floradobrasil/fb7951
http://floradobrasil.jbrj.gov.br/reflora/floradobrasil/fb135670
http://floradobrasil.jbrj.gov.br/reflora/floradobrasil/fb126838
http://floradobrasil.jbrj.gov.br/reflora/floradobrasil/FB130724
http://floradobrasil.jbrj.gov.br/reflora/floradobrasil/fb12913
Plantago sect. Lancifolia is a Mediterranean group of species with complicated nomenclature and taxonomy. In this work I present nomenclatural clarifications and taxonomic rectifications for P. altissima, P. lacustris, P. lanceolata subsp. cyrenaica, P. leiopetala and P. malato-belizii. Plantago maireana is proposed as a new name for P. lanceolata...
Coevolutionary theory suggests that an arms race between plants and herbivores yields increased plant specialized metabolite diversity and the geographic mosaic theory of coevolution predicts that coevolutionary interactions vary across geographic scales. Consequently, plant specialized metabolite diversity is expected to be highest in coevolutiona...
During the copyediting process of this article, the Figure 4 and its caption, present in the original manuscript submitted to the journal, were mistakenly omitted, an error that went unnoticed to editors and authors during the proofing step.
Ruellia reitzii was first collected in 1948 by the prominent botanist Raulino Reitz in Santa Catarina state, southern Brazil, and the species was only known from two gatherings. Because its most recent collection was in 1953, the species was considered possibly extinct. In this work we present the rediscovery of this species, 65 years after its las...
I present here nomenclatural, taxonomic and geographic novelties in the New World Commelina (Commelinaceae). More specifically, the known distribution of C. longicaulis is expanded to include the Amazon region, and an updated nomenclatural account of the synonymy of C. erecta, C. obliqua and C. tuberosa is presented. Also, the New World synonymy of...
Aim
The aim of this study was to resolve the phylogenetic placement of island taxa, reconstruct ancestral origins and resolve competing hypotheses of dispersal patterns and biogeographical histories for oceanic island endemic taxa within subgenus Plantago (Plantaginaceae).
Location
Juan Fernández Islands, the Auckland Islands, Lord Howe Island, Ne...
In this contribution I present novelties and notes on Plantago sect. Virginica. Specifically, I newly describe P. veadeirensis, a critically endangered, narrowly endemic species from northern Goiás state, central Brazil. The new species is remarkable for being the northernmost native Plantago species occurring in South America outside the Andes. Th...
Nomenclatural notes on the species of Gunnera that occur in Brazil and Uruguay are presented. More specifically, I designate a lectotype for the name G. herteri, the only species in Gunnera subg. Ostenigunnera, selected from among the collections of MVM, where Cornelius Osten’s personal herbarium is conserved. I also designate a lectotype for the n...
The Global Strategy for Plant Conservation (GSPC) was established by the Conference of Parties in 2002 to decrease the loss of plant diversity, reduce poverty and contribute to sustainable development. To achieve this overarching goal, the GSPC has established a series of targets, one of which is to ensure that plant diversity is well understood, s...
During the preparation of the treatment of the genus Plantago L. for the Flora Argentina project, dozens of names were identified as needing typification to stabilize their nomenclature. As a result, lectotypes are designated for 40 names, second-step lectotypes for four names, and a neotype for P. grandiflora Meyen. Furthermore, erroneous applicat...
The Global Strategy for Plant Conservation (GSPC) was established by the Conference of Parties in 2002 to decrease the loss of plant diversity, reduce poverty and contribute to sustainable development. To achieve this overarching goal, the GSPC has established a series of targets, one of which is to ensure that plant diversity is well understood, s...
Littorella is a small genus of three herbaceous aquatic species distributed in Europe, northeastern North America and southern South America. Here we provide a complete nomenclatural revision for this genus, where lectotypes are designated for the names of its three accepted species, including the Linnaean name Plantago uniflora, which is the basio...
Plantago sect. Maritima is a group of Mediterranean narrow-leaved plantains whose taxonomy and nomenclature are particularly complex and still unresolved. This work has the objective of advancing the taxonomic knowledge of this section by revising and presenting novelties for the synonymy of P. subulata, including the lectotypification of four name...
Cactaceae is considered the fifth most endangered taxonomic group. In light of this, the aim of this study was to evaluate the efficiency of different low-temperature storage techniques in maintaining the viability of seeds of cacti in different threat categories. Seeds of six cacti taxa were stored in a cold chamber (8 C), a freezer (−5 C), in liq...
Aiming at contributing to the knowledge of the neotropical Commelina, I designate here lectotypes for five species: C. bangii, C. hispida, C. leiocarpa, C. quitensis and C. reflexa. Images of the lectotypes are also provided. With the exception of C. leiocarpa, taxonomic and geographic knowledge of these species is extremely deficient.
The genus Euphorbia is among the most diverse and species-rich plant genera on Earth, exhibiting a near-cosmopolitan distribution and extraordinary chemical diversity, especially across highly toxic macro-and polycyclic diterpenoids. However, very little is known about drivers and evolutionary origins of chemical diversity within Euphorbia . Here,...
We describe here Hoehnea grandiflora, a rare, critically endangered new species of Lamiaceae from high-elevation bogs in southern Brazil. The new species is similar to H. scutellarioides and can be distinguished by its shape and size of leaves, as some floral features. Its conservation status is assessed as Critically Endangered, because the new sp...
Callitriche is a genus of small herbs, ranging from aquatic to amphibious and terrestrial, the taxonomy of the genus is complicated and still unresolved, and knowledge of species distribution is still deficient. The present work aims to contribute to the taxonomic and geographical knowledge of Callitriche in South America by presenting the first re...
This work describes Phyllanthus timboënsis, a narrowly endemic new species from Santa Catarina state, southern Brazil. We provide a detailed morphological description, a distribution map and photographs of the new species, and assess its conservation status. Furthermore, we provide an identification key to species of Phyllanthus that occur in the s...
I present here taxonomic and geographic notes to advance the taxonomic and geographic knowledge of the neotropical Commelina (Commelinaceae). More specifically, I re-establish C. dielsii, a yellow-flowered species only known from the type collected in north-eastern Argentina, which is morphologically allied to C. erecta and C. catharinensis; I lect...
We present here the first account of the naturalised (spontaneous) occurrence of Impatiens balsamina in Brazil, and of I. walleriana in Ceará state, northeastern Brazil. These new records were discovered during herbarium revisions. Both species are widely cultivated as ornamental and were introduced to the Americas from the Old World tropics, and h...
This work presents novelties in the genus Persicaria in Brazil. More specifically, we describe P. sylvestris, a new species from the Atlantic rainforest in subtropical Brazil, propose the new combination P. diospyrifolium and designate a lectotype for its basionym, Polygonum diospyrifolium. The new species has until now been identified as P. acumin...
We present taxonomic and geographic novelties in the genus Plantago from Chile. More specifically, we describe P. nebularis, a new species endemic to Cerro Moreno, Antofagasta region, and propose P. zoellneriana, a new name for P. sericea subsp. araucana. We also lectotypify the name P. sericea, expand the recorded distribution of P. lanceolata and...
A series of nomenclatural and taxonomic misunderstandings have surrounded the montane Indo-Iranian species in Plantago subgenus Plantago. This work has the objective of clarifying the nomenclature and taxonomy for the species and subspecies names available for these plants, in order to determine the correct species names for these entities. More sp...
Alysicarpus ovalifolius (Schumach. & Thonn.) J. Léonard is a legume species used as forage plant, which is originally native to Africa but today has a pantropical distribution. This species is probably expanding its distribution in the neotropics and therefore can be considered a potentially invasive species. In Brazil, the only species of Alysicar...
Aquatic macrophytes are representative flora elements of diverse wetland environments. They play several roles in aquatic ecosystems and are components of paramount importance in maintaining the dynamic and quality of these environments. For coastal lakes, where most aquatic macrophyte studies have been conducted, floristic surveys are continuously...
The flora of Santa Catarina is the best known in Brazil, and yet considerable knowledge gaps remain. Aiming at filling these gaps, we present here 55 new records of vascular plants for this Brazilian state, and the re-collection of four species after more than 50 years. About 50% of new records are non-native in the area. We present short descripti...
Commelina clandestina has been for a long time a problematic citation for the flora of Brazil. Here, I clarify the original publication and authorship of C. clandestina Mart. and C. clandestina Hort.Berol. ex Kunth, designate lectotypes for these names, propose their synonymisation with C. tuberosa, and argue that the seeds from which the type spec...
This contribution describes Phyllanthus eremitus, an extremely narrowly endemic new species from an arenitic rock outcrop in Santa Catarina state, southern Brazil. We assess the conservation status of the new species as critically endangered, because only one population is known, containing less than 30 mature individuals, and it is outside any env...
Historically there has been confusion over the status and identification of Callitriche species in South Africa. Review of herbarium specimens and fieldwork have enabled confirmation of the presence of C. deflexa as a naturalised species in this country and confirmed that C. compressa and specimens named as C. bolusii are conspecific. Field surveys...
Plantago section Maritima comprises a group of Mediterranean narrow-leaved plantains whose taxonomy is still poorly resolved. A nomenclatural and taxonomic study of some relevant names within this group is presented. The names Plantago acanthophylla, Plantago holosteum, Plantago holosteum f. vestita, Plantago penyalarensis, Plantago radicata, Plant...
Here, I present contributions to the knowledge of the genus Plantago (Plantaginaceae) in the Central-West region of Brazil, including the first records of P. australis (more specifically: P. australis subsp. hirtella), P. commersoniana and P. napiformis in this Brazilian region, and the first records of P. major in Mato Grosso state. I also typify...
This contribution presents and describes Tradescantia serrana, a new species from the edges of Araucaria forest in the highlands of southern Santa Catarina state, southern Brazil. Illustrations, photographs and a distribution map for the new species are provided. Here, we also typify T. umbraculifera, a species morphologically related to T. serrana...
Questions
Questions (2)
The recent official publication of PhyloCode has caught my attention, not for new arguments being presented for a system that has already been extensively discussed and, as I see it, whose downsides and problems surpass the envisioned advantages, but surprisingly because of the mediatic coverage it is currently receiving. So many of the major newspapers, which are generally regarded as part of the "mainstream media", are publishing articles and stories praising the "new" PhyloCode as a much-welcome, even necessary, advance to the "terribly outdated" taxonomic classification system currently in use, which "ignores decades of advances in molecular phylogenetics and does not reflect evolutive relationships of organisms". Anyone familiar with the current practices in Systematics is aware that this is malicious disinformation.
In talking with colleagues some have resonated with my impression that, instead of an academic debate, the PhyloCode is becoming a mediatic thing, so that systematists in disagreement with its adoption are branded as "reactionary" and "outdated", not only by the colleagues with whom they disagree but also by the "mainstream media" and possibly the public influenced by it. This type of political interference is negative to Science, and certainly very much unwanted by those endeavouring to advance, improve and refine human understanding of Earth's biodiversity and Natural History.
I think this debate should be kept academic, free as much as possible from this type of political interference. Your thoughts on this topic are very much welcome.
I always thought that ResearchGate could be more transparent in their calculation of RG scores... for example, we don't know exactly how much each individual article counts towards the total score.
That said, I recently got impressed how fast placing questions and answers can increase one's RG score. To me it seems an artificial and too easy way of inflating the score. So I get the impression that the RG score is even less meaningful than most people consider (many people complain about using a mere number to "display" one's worth as scientist).
So my question is: do you fellow RG members agree to this inflation of the RG score due to questions and answers placed? If negative, maybe this could be a good opportunity to present the community's thoughts on the topic to the RG team.