FORMING A LARGE, MULTICENTRE HERBARIUM: HERBARIUM HAUSSKNECHT (JE) JOINS HERBARIUM SENCKENBERGIANUM

Natural history collections constitute Senckenberg's largest and most important research infrastructure. With more than 45 million items, they represent the most extensive natural history collections in Germany, being among the top 10 respective collections worldwide. The Senckenberg herbarium collections (Herbarium Senckenbergianum | Senckenberg - Leibniz Institution for Biodiversity and Earth System Research) are decentralized at the locations Frankfurt (FR), Görlitz (GLM), Weimar (IQW) and Wilhelmshaven, the latter being part of FR (Fig. 1). Herbaria FR and GLM were founded in 1817 and 1811, respectively, while the botanical collections at Weimar and Wilhelmshaven were established more recently. After the integration of GLM into Herbarium Senckenbergianum in 2009, scientific collaboration was strengthened and diversified, access to the collections improved and technical and administrative procedures standardized, while maintaining the physical integrity and regional role of the herbaria. Additionally, the IQW herbarium in Weimar and a center for dinophyte taxonomy in Wilhelmshaven were established (Otte & al., 2011). Recently, an unprecedented step in the landscape of German herbaria was taken with the foundation of the Senckenberg Institute for Plant Form and Function (SIP) in cooperation with Friedrich Schiller University Jena (SIP, Senckenberg Institute for Plant Form and Function). The core of this new research facility is Herbarium Haussknecht (JE), which was established by Carl Haussknecht as a private foundation in 1896. It hosts over 3.6 million specimens and is thus ranked among the 20 largest herbaria worldwide (Thiers, 2022). Herbarium Haussknecht became a member of Herbarium Senckenbergianum in April 2024. With currently more than 5.6 million specimens (Table 1), the expanded Herbarium Senckenbergianum is now responsible for ca. 25% of all herbarium (and fungarium) specimens preserved in Germany (Borsch & al., 2020). Over the last decade, collections of Herbarium Senckenbergianum jointly experienced a mean annual increase of ca. 72.000 specimens, implying ca. 6.5 million specimens will likely be preserved by 2035 (Fig. 2). Following Senckenberg's philosophy and institutional structure, the spatial allocation of the collections and their codes are retained, so that neither the successful tradition nor the important regional ties (e.g., to the Thuringian Botanical Society) and responsibilities are interrupted. A key goal of Senckenberg is to improve access to specimens for both science and society through digitization, and to unlock the treasure trove of data stored in its herbaria. The last decade witnessed a revolution in new techniques being applied to natural history collections in general, and herbaria in particular. This includes imaging (e.g., Schneider & al., 2017; Younis & al., 2020), spectroscopic techniques (e.g., Kothari & al., 2023; Kühn & al., 2024, 2025) and, increasingly, genomic approaches (e.g., Burbano & Gutaker, 2023). Data science and artificial intelligence dramatically improve data extraction and analysis and will impact taxonomy and species discovery (e.g., Hussein & al., 2022; Irschick & al., 2022; Shirai & al., 2022; Wilde & al., 2023; Jones & al., 2024; Karbstein & al., 2024). The concept of the (digital) “extended specimen” embraces these developments (Webster, 2017; Lendemer & al., 2020; Miralles & al., 2020; Hardisty & al., 2022) and has led to extensive international initiatives (e.g., www.dissco.eu, Koureas & al., 2023). These aim to establish closely interlinked physical as well as virtual research platforms providing an infrastructure for a broad range of questions (Johnson & al., 2023). The main idea behind the integration of JE in Herbarium Senckenbergianum is thus to foster collection-based research, curation, and development towards the idea of a global metaherbarium as an open-access resource (Davis & al., 2023). JE benefits from the unique experience Senckenberg has gained over 15 years of integrating natural history collections at 11 locations in Germany in a federal structure (Fig. 1). Along these lines, Senckenberg has coined the term “collectomics” to address the vastly enlarged range of research, made possible by combining the broad variety of new methods with digital integration, modern data science and knowledge derived from specimens. This expands on the concept of museomics, which was originally defined to focus on molecular data generated from museum specimens. As such, collectomics encompasses metadata, images, traits, DNA, and other data that will be extracted in the future with yet unknown applications, all of which being connected to environmental data and other historical contextual information (Collectomics Consortium, in press). This allows us to retrieve biodiversity information from population to ecosystem level, especially with regard to climate and land use change as well nature conservation and biological invasions. To meet these challenges, the team of Herbarium Senckenbergianum comprises 28 scientists covering all taxonomic groups. The focus of individual research teams ranges from systematics, biodiversity genomics, plant ecology, conservation to plant functional ecology. Most recently, a professorship for IT approaches in collection-based research has been established in Jena. Our scientific staff is supported by 19 technical employees and ca. 40 volunteers. The latter personnel does not only support daily handling of specimens and databasing but also contribute to the overall taxonomic expertise and breadth. The immediate effect for scientists is similar to that following the merge of GLM with Herbarium Senckenbergianum in 2009 (Otte & al., 2011): any scholar interested in specimens from the joint Herbarium Senckenbergianum can contact one of the participating institutions, either to visit our collections or to request specimen loans, and receive material from all herbaria in one place or through a single loan. This also includes the service for DNA extractions from specimens, which is organized centrally by the Grunelius Möllgard Laboratory (DNA-Bank | Senckenberg Society for Nature Research) at FR in close coordination with the responsible herbarium curators at each of the different locations. Another main goal is the harmonization of collection strategies in order to better document botanical diversity at different levels. On a national scale, Herbarium Senckenbergianum now covers a German longitudinal transect from western Germany, in particular Hesse (FR), via central Germany, especially Thuringia (JE), to eastern Germany, especially Saxony (GLM) (Fig. 1). At the national level, our collections already form the basis for the provision of identification aids (Müller & al., 2021), virtual herbaria of validated specimens (https://virtherbard.senckenberg.de; https://bestikri.senckenberg.de) and databases (https://chromosomes.senckenberg.de) including local floras (www.flora-frankfurt.de). Access to most of these databases is now centralized on the national information portal “Floraweb” (https://www.floraweb.de/), which is hosted by the German federal government. At the international scale, the biogeographical focus of FR is on vascular plants of Africa (http://www.africanplants.senckenberg.de/root/index.php) and – increasingly so – on Central America, from where 200,000+ specimens will be incorporated into FR soon. GLM's core area is northern and inner Eurasia, while JE houses huge numbers of specimens from Cuba as well as the Middle East. Apart from vascular plants, Herbarium Senckenbergianum also employs experts for algae (FR, Wilhelmshaven), phytoparasitic fungi (GLM), lichens (FR, GLM), and has established a new professorship for bryophytes (JE). The recently launched initiative “CryptoHub” will improve the visibility of Senckenberg's bryophyte and lichen collections. All Senckenberg herbaria have considerable coverage of global liverwort diversity and a particularly large collection of type material. For the lichens, Herbarium Senckenbergianum is among the top 10 reference collections for Lecanoromycetes worldwide (according to GBIF), which will be further complemented by the JE collection. IQW remains Senckenberg's Quaternary fossil facility, and Wilhelmshaven represents the Centre of Excellence for Dinophyte Taxonomy (CEDiT, https://www.dinophyta.org/). The founding of the Senckenberg Institute for Plant Form and Function (SIP) at Jena and the extension of Herbarium Senckenbergianum were implemented in the course of the “Anthropocene Biodiversity Loss” program, which is now permanently established at Senckenberg and was made possible thanks to substantial permanent funding by the Leibniz Association. We also thank the technicians and supporters of Herbarium Senckenbergianum: Luisa Otto, Heike Kappes, Viola Ziller, Micheline Middeke, Gerald Utschig, Evelin Haase, Susann Döring, Maurice Scheidler, Renate Christian, Michaela Schwager, Rainer Döring, Jörg Lorenz, Noel Lichtner, Siegfried Bräutigam, Petra Gebauer, Hans-Werner Otto, Herbert Boyle, Andrea Todt, Gabriele Reislöhner, Sergey Pfaff, Hans-Joachim Zündorf, Anne-Kathrin Pilz and the large number of further volunteers that cannot all be mentioned here.