Thorsten Krömer

University of Veracruz | UV · Centro de Investigaciones Tropicales

Background: The Bromeliaceae family has undergone one of the most remarkable adaptive radiations within angiosperms, partly due to its diversity of reproductive strategies. However, pollinators are known for only 4 % of its about 3,800 species. Questions: What is the flowering pattern like? Which are the characteristics of nectar? What is the bre...

En este ensayo presentamos un resumen de las aportaciones que ha realizado el herbario CITRO en los 15 años que lleva en funcionamiento, las cuales dividiremos por secciones (p.ej. Colecciones, Nuevas especies de plantas, Libros, Tesis florísticas, Educación no formal, base de datos Herbarium.D, Plantas endémicas, Metas y proyectos futuros) y harem...

Para recopilar diferentes perspectivas y líneas de investigación que se desarrollan en el Centro de Investigaciones Tropicales de la Universidad Veracruzana (Citro-uv) (https://www.uv.mx/citro/), 17 académicos del Citro-uv fueron entrevistados. Como resultado del análisis de las respuestas presentamos, primero, una breve descripción sobre la situac...

La Sierra de Chiconquiaco (SC) es una formación geológica ubicada en la región centro del estado de Veracruz, con una superficie de 3,632 km². La literatura más reciente considera que alberga una riqueza de 3,016 especies de plantas vasculares, el 35% de la flora del estado. Sin embargo, más del 70% de su superficie se encuentra transformada en zon...

Aim Endemic species, characterised by limited geographic ranges, face a high risk of extinction. The neotropical region harbours diverse ecosystems and a substantial number of endemic species, thus identifying areas of high endemism is crucial for protecting unique and threatened species and ecosystems. Vascular epiphytes—nonparasitic plants that g...

Las epífitas son plantas que crecen de forma no parasitaria sobre otra planta, principalmente en troncos o copas de árboles, sin contacto con el suelo durante toda su vida. A diferencia de las plantas parásitas o muérdagos, no obtienen directamente ni agua ni nutrientes de sus hospederos, solo los requieren como soporte para acceder a mejores condi...

Endemic species have a limited distribution and are only found in a specific geographic region, for example, a small area within a state. This leads to a higher risk of extinction in case of habitat destruction, making them key elements for establishing and promoting conservation plans. However, endemism is a relative criterion since there are diff...

Background: The terrestrial bromeliad Puya ctenorhyncha is a near-threatened endemic species that grows between 2,500-4,050 m asl. Hypotheses: Hummingbirds are the most important visitors of this plant given its morphological and floral traits. Study site: The study was carried out along the “Death Road”, located in the Yungas montane cloud fores...

The Neotropical realm hosts some of the Earth's most species-rich biodiversity hotspots, with vascular epiphytes significantly contributing to this diversity, regionally accounting for up to 39% of the vascular flora. However, many regions of the Neotropics where epi-phytic species of restricted distribution are reported coincide with threatened ec...

Los cambios en la estructura vegetal tienen consecuencias sobre la temperatura y la humedad del aire de los ecosistemas, teniendo un efecto en el desarrollo de las plantas, pues influyen indirectamente sobre procesos morfológicos y eco-fisiológicos. Esto puede ser investigado a través de grupos sensibles a las perturbaciones, como los helechos, así...

The contributions of the herbarium CITRO In the herbarium there are 1,396 herborized and mounted specimens, including a high number of pteridophytes and epiphytes. The herbarium has contributed to the creation of digital and printed books. The existence of the herbarium has facilitated the discovery of 13 new species for science.

Bromeliads fascinate with their spectacular inflorescences, colorful bracts, and beautiful flowers, and increase their charm even more when we observe that they are visited by a hummingbird, bat, or an insect. However, there is a genus of the subfamily Bromelioideae that is somewhat shy because it is hardly possible to observe its hidden flowers wi...

Understanding the mechanisms driving community assembly has been a major focus of ecological research for nearly a century, yet little is known about these mechanisms in commensal communities, particularly with respect to their historical/evolutionary components. Here, we use a large-scale dataset of 4,440 vascular plant species to explore the rela...

Las especies endémicas tie-nen una distribución restringida, lo que conlleva un mayor riesgo de extinción en caso de destrucción de su hábitat. Algunas de estas especies pertenecen a grupos poco conocidos, cuya determinación taxonómica requiere del apoyo de un especialista. Por esta razón, en los herbarios frecuentemente se encuentran ejemplares ma...

The Neotropical realm hosts some of the Earth’s most species-rich biodiversity hotspots, with vascular epiphytes significantly contributing to this diversity. However, many regions of the Neotropics where epiphytic species of restricted distribution are reported coincide with threatened ecosystems, such as the tropical montane cloud forest. Moreove...

In this work, we contribute to the knowledge of how two environmental gradients (elevation and forest-use intensity) interactively affect the tropical plant diversity of six different vascular plant groups (trees, shrubs, lianas, terrestrial herbs, epiphytes, and ferns). The results were obtained in the frame of the interdisciplinary research proje...

Question Understanding the specific distribution patterns of vascular plants on different spatial scales is central in ecology and conservation. We evaluate distribution patterns of five plant life-forms (climbers, epiphytes, herbs, shrubs, and trees) along the elevation gradient and geographic space of a mountain system, analyzing climate, topogr...

Mesoamerican mountains are important centers of endemism and diversity of epiphytes. The Sierra Madre of Chiapas in southeastern Mexico is a mountainous region of great ecological interest due to its high biological richness. We present the first checklist of epiphytes for this region based on a compilation of various information sources. In additi...

Mesoamerican mountains are important centers of endemism and diversity of vascular epiphytes. The Sierra Madre of Chiapas in southeastern Mexico is a mountainous region of great ecological interest due to its high biological richness. We present the first checklist of epiphytes for this region based on a compilation of various information sources.

The Bromeliaceae family has been used as a model to study adaptive radiation due to its terrestrial, epilithic, and epiphytic habits with wide morpho-physiological variation. Functional groups described by Pittendrigh in 1948 have been an integral part of ecophysiological studies. In the current study, we revisited the functional groups of epiphyti...

The scientific work of Alexander von Humboldt was influenced by his interaction with the diversity and natural wealth of the Neotropics. He proposed that climate determines plant diversity along elevational gradients based on his observations. Here, we evaluated the most prominent climate-based hypotheses in explaining plant diversity along an elev...

The evaluation of the conservation status of selected groups of epiphytes (Araceae, Peperomia, Phlegmariurus, grammitid ferns), in Veracruz, Mexico is described.

El género Greigia Regel se distribuye desde México hasta Chile e incluye 37 especies terrestres y/o rupícolas, la mayoría de ellas sudamericanas. En México habitan tres, todas endémicas, principalmente en bosques mesófilos de montaña y de pino-encino de los estados de Chiapas, Oaxaca y Veracruz. La representación de estas especies en colecciones in...

Variation in leaf functional traits along environmental gradients can reveal how vascular epiphytes respond to broad‐ and small‐scale environmental gradients. Along elevational gradients, both temperature and precipitation likely play an important role as drivers of leaf trait variation, but these traits may also respond to small‐scale changes in l...

Los botánicos y naturalistas alemanes Christian Julius Wilhelm Schiede (1798-1836) y Ferdinand Deppe (1794-1861) exploraron la flora de México por varios años, a partir de 1826. Ellos colectaron extensas muestras de plantas, que formaron una parte importante para la compilación de la flora del país. Muchos de estos ejemplares históricos, incluyendo...

El término hemiepífitas ha sido usado para las aráceas y otras trepadoras (p.ej. Clusia, Ficus), a veces distinguiendo entre hemiepífitas primarias (HP) y secundarias (HS) como formas de crecimiento diferentes. (Putz y Holbrook 1986; Gentry y Dodson 1987; Nadkarni et al. 2001). Las HP germinan y pasan su estado juvenil como epífitas y posteriorment...

Aunque se espera que los síndromes de polinización reflejen la adaptación a los polinizadores primarios, los rasgos del síndrome pueden no excluir a polinizadores secundarios, que también pueden desempeñar un papel en la evolución floral 8. Por ello es importante determinar la efectividad de los polinizadores (p.ej. polen depositado, removido y sem...

Background and Aims Epiphytes are an important component of tropical forests, also they are sensitive to disturbance and deforestation caused by humans, since they depend on their host trees and the micro environmental conditions that these provide. The aim of this study was to analyze the differences in species richness, composition, and vertical...

Como parte de las charlas “Tardes de Ciencia” organizadas por la Dirección General de Investigaciones de la Universidad Veracruzana, el Dr. Thorsten Krömer, investigador del Centro de Investigaciones Tropicales realizo la presentación titulada “Plantas del aire: la vida fascinante de las epífitas”. Esta participación se enmarca en el último volumen...

Intraspecific variation in floral traits, such as nectar, could lead to differences in the identity and pollinator effectiveness of visitors between populations of a flowering plant. We studied the bat-pollinated bromeliad species Pseudalcantarea viridiflora to determine whether there are differences in the identity of its pollinators and in its ne...

Dos de las familias más carismáticas de aves y plantas son exclusivas del continente americano y las podemos apreciar principalmente en las regiones tropicales: Trochilidae y Bromeliaceae. En la primera familia encontramos 343 especies de colibríes, también llamados picaflores o chupamirtos, que son las aves más pequeñas del mundo (el más diminuto...

Los bosques del trópico americano (Neotrópico) se encuentran entre los más biodiversos del planeta. Alexander von Humboldt y Thomas Beltson, algunos de los primeros naturalistas que llegaron a las costas del Caribe a finales del siglo xviii y mediados del xix describieron la vegetación como selvas densas y exuberantes. En sus reportes de viaje dest...

Dentro de las plantas con flores existen unas que destacan del resto: las orquídeas (familia Orchidaceae). Estas plantas son muy codiciadas por los aficionados botánicos y coleccionistas debido a las floraciones espectaculares que presentan. En ellas es posible encontrar tanto flores diminutas que requieren de una lupa para apreciarlas, como en el...

Plant functional traits impact the fitness and environmental niche of plants. Major plant functional types have been characterized by their trait spectrum, and the environmental and phylogenetic imprints on traits have advanced several ecological fields. Yet, very few trait data on epiphytes, which represent almost 10% of vascular plants, are avail...

In the genus Spathiphyllum (Araceae), pollination studies and observations mainly suggest that male euglossine bees (Euglossini: Apidae) are the main pollinators, and Spathiphyllum species seem to fit perfectly in the perfume flower pollination syndrome. Other flower visitors, mainly stingless bees (Meliponini), are frequently observed but mostly r...

Background: Tropical montane forests are important reservoirs of carbon and biodiversity but are threatened by deforestation and climate change. It is important to understand how forest structure and aboveground biomass change along gradients of elevation and succession. Questions: What are the interactive effect of elevation and two stages of succ...

This data paper describes a new, comprehensive database (BIOVERA-Epi) on species distributions and leaf functional traits of vascular epiphytes, a poorly studied plant group, along gradients of elevation and forest-use intensity in the central part of Veracruz State, Mexico. The distribution data include frequencies of 271 vascular epiphyte species...

Target capture has emerged as an important tool for phylogenetics and population genetics in non-model taxa. Whereas developing taxon-specific capture probes requires sustained efforts, available universal kits may have a lower power to reconstruct relationships at shallow phylogenetic scales and within rapidly radiating clades. We present here a n...

Here, we describe BIOVERA-Tree, a database on tree diversity, community composition, forest structure and functional traits collected in 120 forest plots, distributed along an extensive elevational gradient in Veracruz State, Mexico. BIOVERA-Tree includes information on forest structure from three levels of forest-use intensity, namely old-growth,...

Much attention has been directed to understandingspecies richness patterns, but adding an evolutionary perspectiveallows us to also considerthe historical processes determining current diversity patterns. We analyzedphylogenetic patternsof fern species assemblagesin 868 plots along a wide rangeof elevational (0-4000 m) and latitudinal (0°-23°N) gra...

This data paper describes a new, comprehensive database (BIOVERA-Epi) on species distributions and leaf functional traits of vascular epiphytes, a poorly studied plant group, along gradients of elevation and forest-use intensity in the central part of Veracruz State, Mexico. The distribution data includes frequencies of 271 vascular epiphyte specie...

Change and intensification of forest use alter tropical ecosystems, influencing biodiversity and, subsequently, ecosystem functioning. The implications of eroding biodiversity may go beyond decreases in species diversity, resulting in changes of functional diversity, that is, the diversity of ecological strategies present in the community, and func...

Here, we describe BIOVERA-Tree, a database on tree diversity, community composition, forest structure, and functional traits collected in 120 forest plots distributed along an extensive elevational gradient in Veracruz State, Mexico. BIOVERA-Tree includes information on forest structure from three levels of forest-use intensity, namely old-growth,...

Hemiepiphytic plants are defined by their ontogeny. They germinate on a host tree but later establish root contact with the soil. Most hemiepiphytes remain structurally dependent on their host for their entire life, but some, often referred to as stranglers, develop pseudotrunks that allow them to outlive their host. Unfortunately, the terminology...

Target capture emerged as an important tool for phylogenetics and population genetics in non-model taxa. Whereas developing taxon-specific capture probes requires sustained efforts, available universal kits may have a lower power to reconstruct relationships at shallow phylogenetic scales and within rapidly radiating clades. We present here a newly...

Background and Aims: The species of Araceae are known for their diversity of life forms; however, the terminology regarding this group generates conceptual confusion within the scientific community. Our objective was to demonstrate the current conceptual confusion based on the literature, herbarium vouchers vs. observations and field data. Methods...

El Centro de Investigaciones Tropicales (citro) de la Universidad Veracruzana fue fundado en Xalapa, Veracruz, en agosto de 2007. En el citro se realiza investigación interdisciplinaria con el objetivo de comprender, atender y proponer soluciones a problemas relacionados con la diversidad biocultural, la conservación biológica y el manejo de los re...

Los bosques húmedos tropicales están dentro de los tipos de vegetación más ricos en especies de la tierra, sin embargo, nuestra comprensión de su diversidad es todavía fragmentaria, a pesar de la alarmante tasa de destrucción de estos bosques. Para estudiar el impacto de la influencia antrópica sobre la diversidad de epífitas vasculares y orquídeas...

En este capítulo se describen las actividades que han contribuido a la conservación y uso de las Orquídeas realizadas por investigadores y estudiantes del Centro de Investigaciones Tropicales de la Universidad Veracruzana

The aim of this work was to compile and synthesize information about the diversity and distribution of epiphytic angiosperms in Veracruz State to obtain updated data of this important plant group. Based on the revision of herbarium material and specialized literature, as well as the collection of botanical specimens, we recorded a total of 21 famil...

We describe Anemia tabascana (Anemiaceae), a new species from the state of Tabasco in southeastern Mexico. This species is similar to Anemia phyllitidis and Anemia×paraphyllitidis; however, A. tabascana has free veins in the pinnae, and the rachis and distal part of the stipe are glabrescent (vs. at least sparsely pubescent in presumably related sp...

Hummingbirds and bromeliad species of the genus Puya occur exclusively in the Neotropics. Their interaction is important for the reproduction and genetic variability of these plants. To understand this relationship, it is important to study the phenology of Puya species, their floral characteristics, and their floral visitors. In this work, we stud...

Aim To assess the range size patterns of ferns and lycophytes along elevational gradients at different latitudes in an ecographical transition zone and search for predictors of range size from a set of environmental factors. Location Mexico, from 15° to 23° N. Taxon Ferns and lycophytes. Methods All terrestrial and epiphytic species were recorde...

At least half of the 3600 species of Bromeliaceae are pollinated by hummingbirds. There is little doubt that the four to 12 evolutionary shifts towards and c. 32 shifts away from hummingbird pollination opened new evolutionary spaces for bromeliad diversification, and that hummingbird pollination has led to increased bromeliad diversification rates...

Hummingbirds and bromeliad species of the genus Puya occur exclusively in the Neotropics. Their interaction is important for the reproduction and genetic variability of these plants. To understand this relationship, it is important to study the phenology of Puya species, their floral characteristics, and their floral visitors. In this work, we stud...

Evaluación del grado de amenaza de Puya ctenorhyncha L.B.Sm. (Bromeliaceae).

Evaluación del grado de amenaza de Puya dyckioides (Baker) Mez (Bromeliaceae).

Evaluación del grado de amenaza de Puya fosteriana L.B.Sm. (Bromeliaceae).

Evaluación del grado de amenaza de Puya ibischii R.Vásquez (Bromeliaceae).

Evaluación del grado de amenaza de Puya herzogii Wittm. (Bromeliaceae).

At least half of the 3600 species of Bromeliaceae are pollinated by hummingbirds. There is little doubt that the four to 12 evolutionary shifts towards and c. 32 shifts away from hummingbird pollination opened new evolutionary spaces for bromeliad diversification, and that hummingbird pollination has led to increased bromeliad diversification rates...

Vascular epiphytes are a diverse and conspicuous component of biodiversity in tropical and subtropical forests. Still, the patterns and drivers of epiphyte assemblages are poorly studied in comparison to soil‐rooted plants. Our current knowledge about diversity patterns of epiphytes mainly stems from local studies or floristic inventories, but this...

Aim: To disentangle the influence of environmental factors at different spatial grains (regional and local) on fern and lycophyte species richness and ask how regional and plot-level richness are related to each other. Location: Global. Time period: Present. Major Taxa studied: Ferns and lycophytes. Methods: We explored fern and lycophyte species r...

Evaluación del grado de amenaza de Puya cochabambensis R.Vásquez & Ibisch (Bromeliaceae).

Aims Habitat loss and fragmentation are the main threats to biodiversity in tropical forests. Agroecosystems such as shaded cocoa plantations (SCP) provide refuge for tropical forest biota. However, it is poorly known whether the interspecific ecological interactions are also maintained in these transformed habitats. We evaluated the diversity, rep...

Question Land‐use change and intensification are currently the most pervasive threats to tropical biodiversity. Yet, their effects on biodiversity change with elevation are unknown. Here, we examine how tree diversity and community composition vary with elevation and how the effects of forest use intensity on tree diversity and community compositio...

La Sierra de Zongolica forma parte de la región de las Altas Montañas del estado de Veracruz, presenta un gradiente altitudinal desde los 80 a más de 3,000 msnm, incluyendo el Bosque Mesófilo de Montaña (BMM) como uno de los ecosistemas más notables en esta zona. Entre los grupos de plantas más representativos de este ecosistema se encuentran las p...

Los helechos arborescentes de la familia Cyatheaceae en el estado de Veracruz están representados por tres géneros (Alsophila, Cyathea y Sphaeropteris) y 13 especies. Estas plantas crecen en bosques montanos húmedos y selvas tropicales, donde están amenazadas por la deforestación y fragmentación de su hábitat, además del saqueo por usos ornamentale...

Las pteridófitas presentan su mayor diversidad entre los 1,000 y 2,000 msnm, debido a que la humedad ambiental en estas alturas intermedias es alto y constante, encontrándose en ecosistemas como el bosque mesófilo de montaña. Sin embargo, este tipo de vegetación se ve afectado por actividades antrópicas como la deforestación y fragmentación, result...

Aim Understanding patterns of tropical plant diversity and their vulnerability to anthropogenic disturbance at different spatial scales remains a great challenge in ecology and conservation. Here, we study how the effects of forest‐use intensity on vascular epiphyte diversity vary along a tropical elevational gradient. Location 3,500‐m elevational...

We analyzed the composition and diversity of orchids and host trees (phorophytes) in a set of cloud forest fragments, assessing how different land use types affects them. Terrestrial and epiphytic orchids were recorded in three habitats surrounded by different types of land use: mature cloud forest (MF), riparian forested belts (RF) crossing pastur...

IUCN conservation assessment of Araceae from Veracruz State, Mexico

En el bosque, especialmente en las selvas tropicales, hay muchas especies de lianas. Pero ¿qué son las lianas, para qué sirven, para qué se usan? Las lianas son un grupo de plantas que se caracterizan por no poder sostenerse por sí mismas, por eso se apoyan de un árbol o arbusto y se enredan en él para poder crecer y trepar en busca de luz solar, l...