Josef Brunnthaler, self-taught Austrian botanist and algologist, became the librarian of the Zoologisch-botanishen Gesellschaft in 1895 and two years later founded the Kryptogamen-Tauschanstalt (Cryptogam exchange institute). In 1908 he became conservator of the Botanical Museum at the University of Vienna. Early in his career he published three papers in Austria: "Ueber eine monströse Wuchsform von Polyporus squamosus (Huds.)" (1896), "Pogonatum nanum xaloides" (1897), and "Plankton-studien" (1900). During the second half of 1909 he made a collecting tour in central and southern Africa. He arrived at Tanga, German East Africa (now in north-eastern Tanzania) on 16 July and visited the nearby Amani research centre (later the headquarters of the East African Malaria Research Organisation), proceeded by sea to Beira, Mozambique, and visited the Victoria Falls and Bulawayo. Arriving in Cape Town on 10 October he met Dr H.R.R. Marloth*. With Cape Town as his base he collected plants on Table Mountain and made collecting trips to Caledon, Genadendal, and several places in the Karoo. He then travelled to Port Elizabeth and collected in the Addo region, north-east of the city. Proceeding to Durban by sea he travelled inland to Van Reenen's Pass. He returned to Vienna in January 1910, having accumulated extensive collections of woody plants, fruits, seeds, lichens, mosses, liverworts, reptiles, amphibians, termites, and photographs.
Brunnthaler published his "Ergebnisse einer botanischen Forschungreise nach Deutsch-Ostafrika und Südafrika" (Results of a botanical research journey to German East Africa and South Africa) in the Denkschriften der Mathematisch-naturwissenschaftlichen Klasse der Kaiserlichen Akademie der Wissenschaften (1913). Among others this paper included accounts of the Hepaticae (liverworts) by F. Stephani and of the mosses by V.F. Brotherus. Other papers that Brunnthaler based on his visit were "Vegetationsbilden aus Südafrika (Karroo und Dornbush)" (Vegetationsbilder, 1911) and "Aus dem Succulentengebiet Südafrikas" (Zeitschrift für Gärtner und Gartenfreund, 1911).
In 1911 Brunnthaler took part in a journey to Dalmatia (along the Adriatic coast of Croatia). He became ill the next year and died two years later. Many papers by him dealt with the fresh water algae, particularly of the class Chlorophyceae (green algae), of Germany and Austria. His lichens were presented to A. Zahlbruckner, who described from them a large number of new species in 1926.