Science Enabled by Specimen Data

Louw, G. J., L. J. Potgieter, and D. M. Richardson. 2024. Myoporum (Scrophulariaceae): Introduction, naturalization, and invasion of an enigmatic tree genus in South Africa. South African Journal of Botany 168: 529–541.

Myoporum is a genus of trees and shrubs native to the Northern Hemisphere that has been introduced to many parts of the world, mainly for ornamental purposes. We assessed the introduction history, distribution, and extent of naturalization/invasion for Myoporum species in South Africa.Information was collated to determine key events associated with the introduction, establishment, and naturalization of Myoporum in South Africa. Data were collated to determine the current distribution of the genus in South Africa. Twenty sites in the Western Cape were sampled to determine correlates of naturalization. Myoporum was first recorded in South Africa in 1934. Three species were confirmed to be present in South Africa: M. insulare, M. laetum and M. montanum (37 %, 25 % and 24 % of all iNaturalist records respectively). Most records are from the Western Cape (91 %) and small parts of the Eastern Cape; isolated populations occur in Gauteng and the Northern Cape. We could not confirm the presence M. petiolatum, M. tenuifolium or M. tetrandrum. Field surveys revealed widespread naturalization of M. insulare (46 % of all Research Grade observations in iNaturalist); this species was categorized code D1 in the introduction-naturalization-invasion continuum. Myoporum laetum (C3) and M. montanum (C2) are also widely naturalized but over smaller areas. Naturalized populations comprised predominantly juvenile M. insulare plants occurring in highly disturbed (transformed) habitats. Formal risk analyses for all Myoporum species in South Africa are needed as the basis for re-evaluation of their status in national legislation.

Ramírez-Barahona, S. 2024. Incorporating fossils into the joint inference of phylogeny and biogeography of the tree fern order Cyatheales R. Warnock, and M. Zelditch [eds.],. Evolution.

Present-day geographic and phylogenetic patterns often reflect the geological and climatic history of the planet. Neontological distribution data are often sufficient to unravel a lineage’s biogeographic history, yet ancestral range inferences can be at odds with fossil evidence. Here, I use the fossilized birth–death process and the dispersal–extinction cladogenesis model to jointly infer the dated phylogeny and range evolution of the tree fern order Cyatheales. I use data for 101 fossil and 442 extant tree ferns to reconstruct the biogeographic history of the group over the last 220 million years. Fossil-aware reconstructions evince a prolonged occupancy of Laurasia over the Triassic–Cretaceous by Cyathealean tree ferns, which is evident in the fossil record but hidden from analyses relying on neontological data alone. Nonetheless, fossil-aware reconstructions are affected by uncertainty in fossils’ phylogenetic placement, taphonomic biases, and specimen sampling and are sensitive to interpretation of paleodistributions and how these are scored. The present results highlight the need and challenges of incorporating fossils into joint inferences of phylogeny and biogeography to improve the reliability of ancestral geographic range estimation.

Anest, A., Y. Bouchenak-Khelladi, T. Charles-Dominique, F. Forest, Y. Caraglio, G. P. Hempson, O. Maurin, and K. W. Tomlinson. 2024. Blocking then stinging as a case of two-step evolution of defensive cage architectures in herbivore-driven ecosystems. Nature Plants.

Dense branching and spines are common features of plant species in ecosystems with high mammalian herbivory pressure. While dense branching and spines can inhibit herbivory independently, when combined, they form a powerful defensive cage architecture. However, how cage architecture evolved under mammalian pressure has remained unexplored. Here we show how dense branching and spines emerged during the age of mammalian radiation in the Combretaceae family and diversified in herbivore-driven ecosystems in the tropics. Phylogenetic comparative methods revealed that modern plant architectural strategies defending against large mammals evolved via a stepwise process. First, dense branching emerged under intermediate herbivory pressure, followed by the acquisition of spines that supported higher speciation rates under high herbivory pressure. Our study highlights the adaptive value of dense branching as part of a herbivore defence strategy and identifies large mammal herbivory as a major selective force shaping the whole plant architecture of woody plants. This study explores the evolution of two traits, branching density and spine presence, in the globally distributed plant family Combretaceae. These traits were found to have appeared in a two-step process in response to mammalian herbivory pressure, revealing the importance of large mammals in the evolution of plant architecture diversity.

Minghetti, E., P. M. Dellapé, M. Maestro, and S. I. Montemayor. 2024. Evaluating the climatic suitability of Engytatus passionarius Minghetti et al. (Heteroptera, Miridae) as a biological control agent of the invasive stinking passion flower Passiflora foetida L. in Australia through ecological niche models. Biological Control 191: 105461.

Passiflora foetida is a climbing vine, native to the Neotropical Region that is causing major economic and ecological damage in Australia, where it is rapidly spreading. Traditional control options, such as cutting, manual uprooting, and herbicide applications are only effective for local management. Currently, the plant bug Engytatus passionarius is the most promising biological control agent. Specificity tests performed in its native range in Argentina suggest it is highly specific to the plant, and it has not been observed in the field associated with other plants. As climate determines the establishment of insects, knowing if the environmental conditions suit their requirements is key to introducing a species in a region. Also, an overlap between the climatic niches of species is an indicator of similar requirements. To explore the possibilities of a successful establishment of E. passionarius in Australia, ecological niche models (ENM) were built for the plant bug and for the vine and their overlap was measured. The ENM projected to Australia recognized suitable environmental conditions for the establishment of E. passionarius in several regions where P. foetida is present, both for current and future scenarios. Moreover, the niche of the plant bug is almost completely overlapped with that of the vine. All the aforementioned evidence seems to indicate that E. passionarius has a good chance to become an effective biological control agent of P. foetida.

Ract, C., N. D. Burgess, L. Dinesen, P. Sumbi, I. Malugu, J. Latham, L. Anderson, et al. 2024. Nature Forest Reserves in Tanzania and their importance for conservation S. S. Romanach [ed.],. PLOS ONE 19: e0281408.

Since 1997 Tanzania has undertaken a process to identify and declare a network of Nature Forest Reserves (NFRs) with high biodiversity values, from within its existing portfolio of national Forest Reserves, with 16 new NFRs declared since 2015. The current network of 22 gazetted NFRs covered 948,871 hectares in 2023. NFRs now cover a range of Tanzanian habitat types, including all main forest types—wet, seasonal, and dry—as well as wetlands and grasslands. NFRs contain at least 178 of Tanzania’s 242 endemic vertebrate species, of which at least 50% are threatened with extinction, and 553 Tanzanian endemic plant taxa (species, subspecies, and varieties), of which at least 50% are threatened. NFRs also support 41 single-site endemic vertebrate species and 76 single-site endemic plant taxa. Time series analysis of management effectiveness tracking tool (METT) data shows that NFR management effectiveness is increasing, especially where donor funds have been available. Improved management and investment have resulted in measurable reductions of some critical threats in NFRs. Still, ongoing challenges remain to fully contain issues of illegal logging, charcoal production, firewood, pole-cutting, illegal hunting and snaring of birds and mammals, fire, wildlife trade, and the unpredictable impacts of climate change. Increased tourism, diversified revenue generation and investment schemes, involving communities in management, and stepping up control measures for remaining threats are all required to create a network of economically self-sustaining NFRs able to conserve critical biodiversity values.

Roberts, J., K. Dhileepan, and S. Florentine. 2024. A review of the biology, distribution, and management challenges posed by the invasive weed Ziziphus mauritianaL., with special reference to its invasion in Australia. Weed Research.

Ziziphus mauritiana is an economically detrimental and environmentally destructive plant in non‐native areas where it has escaped cultivation. It forms dense, impenetrable thickets that restrict the movement of livestock across the landscape and has the capacity to alter various ecological functions at the site of invasion, all of which contribute towards land degradation and the reduction of economic profitability. Although there are several management strategies implemented to control Z. mauritiana, it is clear that no single‐method approach will effectively control the species in the long‐term. Whilst chemical and mechanical methods appear to show promising results, they tend to be restricted to areas that are easily accessible and, even so, can be challenging and laborious to treat evenly across dense thicket areas. Several prospective biological control agents have been identified for Z. mauritiana, although further investigations are required to ascertain the host specificity, and to explore and identify their climatic and environmental suitability of host specific agents for release in non‐native regions. Ecological burning alone is not effective in controlling Z. mauritiana and will likely increase its emergence. As such, it could be adopted as part of an integrated management approach to assist other methods for long‐term control, but again the development of such an approach requires further investigation. To contribute towards the control of Z. mauritiana, this review explores its biology, distribution and management challenges whilst identifying areas of research that will assist in the long‐term and confident control of the species, with an emphasis on its invasion in Australia.

(no abstract available)

Rodríguez-Merino, A. 2023. Identifying and Managing Areas under Threat in the Iberian Peninsula: An Invasion Risk Atlas for Non-Native Aquatic Plant Species as a Potential Tool. Plants 12: 3069.

Predicting the likelihood that non-native species will be introduced into new areas remains one of conservation’s greatest challenges and, consequently, it is necessary to adopt adequate management measures to mitigate the effects of future biological invasions. At present, not much information is available on the areas in which non-native aquatic plant species could establish themselves in the Iberian Peninsula. Species distribution models were used to predict the potential invasion risk of (1) non-native aquatic plant species already established in the peninsula (32 species) and (2) those with the potential to invade the peninsula (40 species). The results revealed that the Iberian Peninsula contains a number of areas capable of hosting non-native aquatic plant species. Areas under anthropogenic pressure are at the greatest risk of invasion, and the variable most related to invasion risk is temperature. The results of this work were used to create the Invasion Risk Atlas for Alien Aquatic Plants in the Iberian Peninsula, a novel online resource that provides information about the potential distribution of non-native aquatic plant species. The atlas and this article are intended to serve as reference tools for the development of public policies, management regimes, and control strategies aimed at the prevention, mitigation, and eradication of non-native aquatic plant species.

Calvente, A., A. P. Alves da Silva, D. Edler, F. A. Carvalho, M. R. Fantinati, A. Zizka, and A. Antonelli. 2023. Spiny but photogenic: amateur sightings complement herbarium specimens to reveal the bioregions of cacti. American Journal of Botany.

Premise: Cacti are characteristic elements of the Neotropical flora and of major interest for biogeographic, evolutionary, and ecological studies. Here we test global biogeographic boundaries for Neotropical Cactaceae using specimen‐based occurrences coupled with data from visual observations, as a means to tackle the known collection biases in the family.MethodsSpecies richness and record density were assessed for preserved specimens and human observations and a bioregional scheme tailored to Cactaceae was produced using the interactive web application Infomap Bioregions based on data from 261,272 point records cleaned through automated and manual steps.Key ResultsWe find that areas in Mexico and southwestern USA, Eastern Brazil and along the Andean region have the greatest density of records and the highest species richness. Human observations complement information from preserved specimens substantially, especially along the Andes. We propose 24 cacti bioregions, among which the most species‐rich are: northern Mexico/southwestern USA, central Mexico, southern central Mexico, Central America, Mexican Pacific coast, central and southern Andes, northwestern Mexico/extreme southwestern USA, southwestern Bolivia, northeastern Brazil, Mexico/Baja California.ConclusionsThe bioregionalization proposed shows biogeographical boundaries specific to cacti, and can thereby aid further evolutionary, biogeographic, and ecological studies by providing a validated framework for further analyses. This classification builds upon, and is distinctive from, other expert‐derived regionalization schemes for other taxa. Our results showcase how observation data, including citizen‐science records, can complement traditional specimen‐based data for biogeographic research, particularly for taxa with specific specimen collection and preservation challenges and those that are threatened or internationally protected.This article is protected by copyright. All rights reserved.


As the long-term sustainability of both natural and artificial phytocenoses is under serious threat from biological invaders, the global community is working hard to prevent invasions and rapidly eradicate or halt the spread of invasive species. By tracking the actual spread of “invaders” or predicting areas at risk of invasion, geographic information systems (GIS) and remote sensing of the Earth (RSE) can significantly assist the process of ensuring biosecurity at the state level. Research has shown the potential of remote sensing and GIS applications for invasive species mapping and modeling, even though it is currently restricted to a small number of taxa. This article gives examples of how GIS and RSE can be used to track invasive species like Utricularia australis R. br. and Lemna aequinoctialis Welw. To describe the distribution of species, current Internet databases of species distribution and the author’s own research were used. It also talks about promising ways to find and track the spread of invasive species, like using NDVI indices, chlorophyll and xanthophyll content to find changes in regional biodiversity, some problems with finding changes in biodiversity in agricultural landscapes, and mapping invasion risk. The study also demonstrates how GIS technology may be used to identify agricultural landscape biodiversity using radiometric space data from Sentinel 1, followed by a verification of the findings. The prospects of spatial, spectral, and temporal analysis of images are determined, as they make it possible to outline the boundaries of ecosystems, biometric characteristics of species, characteristics of their current and potential areas of distribution, etc.