Non‐native palms (Arecaceae) as generators of novel ecosystems: A global assessment

Unveiling the overlooked: Current and future distribution dynamics of kissing bugs and palm species linked to oral Chagas disease transmission

Chagas disease, a neglected global health concern primarily transmitted through the bite and feces of kissing bugs, has garnered increasing attention due to recent outbreaks in northern Brazil, highlighting the role of oral transmission facilitated by the kissing bugs species Rhodnius robustus and Rhodnius pictipes. These vectors are associated with palm trees with large crowns, such as the maripa palm (Attalea maripa) and moriche palm (Mauritia flexuosa). In this study, we employ maximum entropy (MaxEnt) ecological niche models to analyze the spatial distribution of these vectors and palm species, predicting current and future climate suitability. Our models indicate broader potential habitats than documented occurrences, with high suitability in northern South America, southern Central America, central Africa, and southeast Asia. Projections suggest increased climate suitability by 2040, followed by a reduction by 2080. This study identifies present and future areas suitable for kissing bugs and palm tree species due to climate change, aiding in the design of prevention and management strategies.

Novel Helicoma and Neohelicosporium (Tubeufiaceae, Tubeufiales) species and two new host records of Helicoma on tropical palms (Arecaceae) from China

Asexual species of Tubeufiaceae are characterised as helicosporous hyphomycetes and are abundantly discovered in tropical and subtropical regions. The present study collected helicosporous fungal samples from rotting tissues of Caryotamitis, Elaeisguineensis and E.oleifera in Xishuangbanna, Yunan Province, China. Fungal isolates were identified, based on the morphological characteristics and multi-gene phylogeny with DNA sequence data of the internal transcribed spacer (ITS), part of the large subunit nuclear rRNA gene (LSU), translation elongation factor 1-alpha gene (tef 1-α) and RNA polymerase II second largest subunit gene (rpb2). Herein, we introduce three new species viz. Helicomaoleifera, Neohelicosporiumguineensis and N.xishuangbannaensis. In addition, we introduce two new host records of Helicomaguttulatum and H.rufum on Caryotamitis. The illustrations of all identified species, detailed descriptions and in-depth phylogenetic analyses are provided. Our results add new knowledge of fungal species associated with palm hosts in southern China. Moreover, our data will contribute to the biodiversity of fungi in tropical China.

Not just females and males: Unravelling the complex sex determinism of the hemp palm, Trachycarpus fortunei

PREMISE

The ornamental Asian palm Trachycarpus fortunei (Arecaceae: Coryphoideae) is widely planted in temperate regions. In Europe, it has spread outside of gardens, particularly on the southern side of the Alps. Sexual expression in the species is complex, varying from dioecy to polygamy. This study investigated (1) sexual floral development and (2) genetic markers implicated in sex determinism.

METHODS

The morphology and anatomy of floral organs at different developmental stages were studied using SEM observations and anatomical section. Sex determinism was explored using a genome-wide association study approach, searching for correlations between 31,000 single-nucleotide polymorphisms and sex affiliation of 122 palms from 21 wild populations.

RESULTS

We observed that sexual differentiation appears late in floral development of T. fortunei. Morpho-anatomical characters of flowers conducive to panmixia were observed, such as well-differentiated septal nectaries that are thought to promote cross-pollination. At the molecular level, homozygous and heterozygous allelic systems with closely linked regions were found for sex determinism in individuals with female and "dominant-male" phenotypes, respectively. Through our wide sampling in the southern Alps, the closely linked genetic regions in males suggest that at least fifteen percent of wild palms are the direct offspring of "males" that can also produce fertile pistillate flowers.

CONCLUSIONS

Trachycarpus fortunei is a further example of unstable sexual expression found in the family Arecaceae and represents an evolutionary path towards an XY genetic system. Our structural and genetic results may explain the high species dispersal ability in the southern Alps.

Iconic but Invasive: The Public Perception of the Chinese Windmill Palm (Trachycarpus fortunei) in Switzerland

Biological invasions strongly increased during the last centuries and are challenging environmental managers worldwide. In this context, public acceptance of management measures is a key factor determining the long-term success of the control of invasive species. However, in the case of charismatic and iconic invasive species, the public has often been unwilling to accept strict management measures. Here, we studied the public perception of the Chinese windmill palm (Trachycarpus fortunei) in Switzerland, which is declared as invasive in southern Switzerland but also recognized as iconic. We conducted a nation-wide online survey in the multilingual and multicultural context of Switzerland, investigating the influence of social and cultural factors on the knowledge of, the attitude toward, and the willingness to control the invasive T. fortunei. Results confirm that the knowledge and perception of invasive plants have a strong social and cultural component and may vary greatly as a function of the cultural background, education level, age, and other social characteristics. Furthermore, information on the invasiveness of the focal species provided during the survey significantly affected informants' perceptions, which are closely related to the acceptance of possible management and control measures. This allows us to highlight the importance of a holistic approach that includes targeted public information when dealing with biological invasions, especially in the case of charismatic and iconic species. Based on the obtained results, we suggest avenues for refining management and control strategies of T. fortunei in Switzerland, many of which generally applicable to other cases of invasive species.

Panmixia and active colonisation of the invasive palm Trachycarpus fortunei (Arecaceae) in Southern Switzerland and Northern Italy as inferred by microsatellites and SNP markers

Trachycarpus fortunei (Arecaceae: Coryphoideae) is an Asian palm that was introduced during the nineteenth century in southern Switzerland and northern Italy as an ornamental plant. In the recent decades, the palm has become an aggressive invasive species in the region. Before this study, the genetic structure and diversity of the naturalised populations were unknown. We aimed at understanding the dynamics of invasion and at comparing the results obtained with two types of markers. This genetic approach aimed at tracing back as far as possible the source of invasive populations comparing historical information found in literature and invasive genetic patterns. The genetic diversity was analysed using eight microsatellites (five were developed for that purpose) and 31′000 SNPs identified through GBS analyses. Genetic analyses were carried out for 200 naturalised individuals sampled from 21 populations in the Canton Ticino (Switzerland) and the provinces of Lombardy and Piedmont (Italy). The observed general panmixia indicates that the expansion of T. fortunei is active in its naturalised areas. The genetic pattern found for both SNPs and microsatellites appears to be related to the colonisation process, with a lack of geographic structure and bottleneck signatures occurring at the colonisation front, distantly from historical sites. This study gives a better understanding of the expansion of T. fortunei and adds new insights to its ecology.

Worldwide Distribution of Antagonistic-Mutualistic Relationships Between Parrots and Palms

Palms, like all plants, show coevolutionary relationships with animals that have been traditionally categorized as mutualistic (seed dispersers and pollinators) or antagonistic (seed predators). This dual perspective, however, has prevented a full understanding of their true interactions with some animal groups, mainly those that do not ingest entire fruits. One clear example is parrots, which have been described to use palm species as feeding resources, while their role as seed dispersers has been largely neglected. Here, we combined fieldwork data with information from the literature and citizen science (i.e., naturalists and nature photographers) on parrot foraging ecology worldwide to evaluate the spatial and taxonomic extent of parrot-palm interactions and to identify the eco-evolutionary factors involved. We identified 1,189 interactions between 135 parrots and 107 palm species in more than 50 countries across the six realms where palms are present as natives or introduced. Combining this information, we identified 427 unique parrot-palm interacting pairs (i.e., a parrot species interacting with a palm species). Pure antagonistic interactions (i.e., parrots just preying on seeds or eating or destroying their non-reproductive parts) were less common (5%) than mutualistic ones (i.e., parrots benefiting by partially preying on the seed or fruit or consuming the pulp of the fruit or the flower but also contributing to seed dispersal and, potentially, pollination; 89%). After controlling for phylogeny, the size of consumed seeds and parrot body mass were positively related. Seed dispersal distances varied among palm species (range of estimated median dispersal distances: 9–250 m), with larger parrots dispersing seeds at greater distances, especially large fruits commonly categorized as megafauna anachronisms (>4 cm length). Although parrot-palm interactions are widespread, several factors (e.g., social behavior, predation fear, food availability, or seasonality) may affect the actual position of parrots on the antagonism-mutualism continuum for different palm species and regions, deserving further research. Meanwhile, the pervasiveness of parrot-palm mutualistic interactions, mainly involving seed dispersal and pollination, should not be overlooked in studies of palm ecology and evolution.