Hedlundia lonetalensis, the Lonetal whitebeam,Meyer, T. (n.d.). Lonetal- Mehlbeere (Sorbus lonetalensis S. Hammel & Haynold). Blumen in Schwaben. Retrieved July 24, 2026, from https://www.blumeninschwaben.de/Zweikeimblaettrige/Rosengewaechse/lonetal.htm is a species of tree in the family Rosaceae endemic to Baden-Württemberg, Germany. It is extremely rare and threatened with extinction.
Description
Vegetative characteristics Hedlundia lonetalensis is a small, up to 6 m tall tree with up to 21 cm wide trunks. If it is cut down, it produces multiple trunks. The plain bark is greyish-brown. Generative characteristics The 4.5–6 cm wide inflorescence bears 30–40 flowers. The strongly pubescent ovary bears white hair. The 6–7 cm wide infructescence bears 10–25 small, round, apple-shaped,Meyer, N., & Hammel, S. (2023). Besondere Arten der Gattung Sorbus: Bemerkungen zu den Eigenheiten der Gattung Sorbus in Baden-Württemberg. Karlsruhe. carmine red accessory fruits. Fertile fruits produce 1–2 brown, 6mm long, 3 mm wide, and 2.5 mm tall seeds. Cytology The chromosome count is 2n = 68. It is a tetraploid plant.Hammel, S., Haynold, B., Gregor, T., & Paule, J. (2015) Ploidie-Bestimmung baden-württem bergischer Bastard-Mehlbeeren. Jh. Ges. Naturkde. Württemberg 171 S. 69-75Meyer, N., & Meierott, L. (2021). Ergänzende Beiträge zur Sorbus-Flora von Bayern. Ber. Bayer. Bot. Ges., 91, 21-48.
Taxonomy It was first published as Sorbus lonetalensis by Steffen Hammel and Bernd Haynold in 2015.Hammel, S., & Haynold, B. (2015). Sorbus lonetalensis–eine neue Mehlbeere aus Baden-Württemberg. Jahreshefte der Gesellschaft für Naturkunde in Württemberg, 171, 077-094.Sorbus lonetalensis S.Hammel & Haynold. (n.d.). International Plant Names Index. Retrieved July 24, 2026, from https://www.ipni.org/n/77157415-1 The type specimen was collected by Steffen Hammel on the 9th of September 2014 south of Herbrechtingen-Bissingen, Baden-Württemberg, Germany at an elevation of 480 m above sea level. The species was moved to the genus Hedlundia as Hedlundia lonetalensis by Alexander Nikolaevitsch Sennikov and Arto Kurtto in 2017.Sennikov, A. N., & Kurtto, A. (2017). A phylogenetic checklist of Sorbus sl (Rosaceae) in Europe. Memoranda Societatis pro Fauna et Flora Fennica, 93, 1-78.Hedlundia lonetalensis (S.Hammel & Haynold) Sennikov & Kurtto. (n.d.-b). International Plant Names Index. Retrieved July 24, 2026, from https://www.ipni.org/n/77164924-1 The plant was first found by Thomas MeyerHammel, S., & Haynold, B. (2017, January 28). Die Gattung Sorbus auf der Schwäbischen Alb – Zwischenbericht und Kartierungstipps. and was first photographed on the 31st of May 2014. Etymology The genus name Hedlundia honours the Swedish botanist Johan Teodor Hedlund. The specific epithet lonetalensis refers to the Lonetal valley in Baden-Württemberg, Germany.Blaich, G. (n.d.). Sorbus lonetalensis S.HAMMEL & HAYNOLD. Retrieved July 24, 2026, from https://www.guenther-blaich.de/pflseite.php?par=Sorbus+lonetalensis
Distribution and habitat It is endemic to Baden-Württemberg, Germany where it occurs in a single location in the south of Herbrechtingen-Bissingen in the Lonetal in between the edge of woodland and open grassland.
Ecology Alsophila caterpillars feed on Hedlundia lonetalensis leaves.
Conservation Hedlundia lonetalensis is extremely rare.Deutsches Zentrum für Luft- und Raumfahrt e. V. & Bundesamtes für Naturschutz (BfN). (2026, January 14). Sorbus lonetalensis S. Hammel & Haynold. Rote Liste Zentrum. Retrieved July 24, 2026, from https://www.rote-liste-zentrum.de/detailseite/?species_uuid=0dca09bb-6d5d-4414-86b1-1d8c19956405Bundesamt für Naturschutz. (n.d.). Sorbus lonetalensis S. Hammel & Haynold. FloraWeb. Retrieved July 24, 2026, from https://www.floraweb.de/php/artenhome.php?suchnr=35367 It is a critically endangered species with only 10 mature individuals occurring on an area of 4 km2 south of Herbrechtingen-Bissingen in the Lonetal. The species doesn't have special legal protection, but the forest where it occurs has been placed under protection. It is threatened by darkening forests due to natural succession and its regeneration is limited by grazing. Only few individuals are able to reproduce, as they fail to flower under dark conditions. The habitat, as well as the number of mature individuals are declining. Three specimens were given to the Botanischer Garten der Universität Ulm for the purpose of ex-situ conservation.
References