Nomenclatural study designates type specimens for Italian alpine plant Sempervivum dolomiticum

A nomenclatural study of the Italian alpine plant Sempervivum dolomiticum Facchini has designated the herbarium specimen TR-BOT 002203 as the lectotype of the name and TR-BOT 002204 as an isotype. The research sought to resolve the previously untotypified name for this chasmophytic species, which is endemic to Italy and occurs in the administrative regions of Veneto and Trentino-Alto Adige/Süd Tirol. The lectotype was collected by Francesco Facchini at “Sas della Porta” on 23 September 1843 and is preserved in the TR herbarium.

The investigators examined relevant literature, scrutinized Facchini’s 1855 protologue and compared it with original material held in the Ambrosi-Facchini and Gelmi collections at the MUSE herbarium in Trento. They applied the nomenclatural guidance cited from McNeill (2014) and Turland et al. (2018). A field survey conducted in summer 2019 also confirmed the species’ current presence at its type locality, Croda del Becco in the Croda Rossa complex. The study was a nomenclatural investigation of type material rather than a broad ecological analysis.

Among seven traced specimens of S. dolomiticum in the TR collections, five were collected by Facchini and two by Enrico Gelmi. The two selected Facchini specimens, TR-BOT 002203 and TR-BOT 002204, were recorded from the same date and locality, and the researchers stated that their plant material was probably part of a single gathering. TR-BOT 002203 was selected as the lectotype based on the condition of the sample and the quality of its accompanying notes; TR-BOT 002204 was designated as an isotype. Although the quality of all the herbarium vouchers examined was low, which the authors attributed probably to difficulties in desiccating and preserving succulent plant tissues, they considered the selected types fully compliant with the species description.

The lectotype label reproduces Facchini’s notes on the occurrence of the plant on three slopes toward the summit and records purple petals and comparisons with other Sempervivum species. Facchini’s original description noted that S. dolomiticum co-occurs with Sempervivum arachnoideum and distinguished it by the absence of apical trichomes in the rosette. Other diagnostic characteristics reported were leaves with marginal hairs, linear-lanceolate leaves and lanceolate petals. The selected locality was compared with the protologue’s reference to “in Alpe Seekofl,” identified as Croda del Becco. Because the Gelmi and Ambrosi-Facchini collections are study herbaria in which notes were added on multiple occasions, a single voucher may have more than one registered code; accordingly, the isotype TR-BOT 002204 also has an additional note registered as TR-BOT 002205.

Subject of Research: Typification of the nomenclatural type material for Sempervivum dolomiticum

Article Title: Typification of the name Sempervivum dolomiticum Facchini ( Crassulaceae )

Article References: Canella, M., Ranjbaran, Y., Behrens, E., Bonomi, C., Orsenigo, S., & Dal Grande, F. (2024). Typification of the name Sempervivum dolomiticum Facchini (Crassulaceae). Italian Botanist, 17, 103-107. https://doi.org/10.3897/italianbotanist.17.119069

Image Credits: AI Generated

DOI: 10.3897/italianbotanist.17.119069

Keywords: Sempervivum dolomiticum, plant typification, lectotype, isotype, nomenclature, Crassulaceae, herbarium collections, Italian Alps, botanical taxonomy, Typification, name, Sempervivum