Arenaria weberbaueri (Muschl.) Montesinos & Iamonico, 2023

Montesinos-Tubée, Daniel B. & Iamonico, Duilio, 2023, Typifications of Andean Arenaria names (Caryophyllaceae), with a nomen novum, Phytotaxa 579 (1), pp. 54-60 : 55

Alsine weberbaueri

Muschler (1911: 448) recognized this species giving a detailed description, the provenance (as “Peruvia: Andes altissime supra Lima, in formatione plantarum pulvinarum et rosulatum, in 4500 m altitudine”), and by citing a specimen (syntype according to the Art. 9.6 of ICN): “WEBERBAUER n. 5160. ― Specimina florigera fructiferaque 1. Aprilis 1903.―Herb. Berol.”.

No specimen was traced at the herbarium B; in fact, as reported by various authors (see e.g., Sleumer 1949, Hiepko 1987), most of the collections housed at B were destroyed during the World War II. Furthermore, no material was either found at MOL and USM, where duplicates of Weberbauer’s collections are chiefly located ( Stafleu & Cowan 1988, HUH-Index of Botanists 2013+). According to the Art. 9.8 of ICN, a neotypification is required. We here choose as the neotype a collection made by one of us (DM-T) deposited at HOXA, which bears four plants from a single gathering (see Art. 9.17 of ICN) that morphologically match the protologue of Alsine weberbaueri concerning the habit (densely pulvinate with a long and thick root), leaves (linear-lanceolate with cuneate base, ciliate on both sides, thick, and petiolate), and flowers [with more or less curved pedicels (ca. 1 cm long), oblong sepals (3–5 mm long), and petals as long as the sepals].

Muschler (1911: 448) described this taxon under Alsine Linnaeus (1753: 272). However, this genus is currently considered as a synonym of Stellaria Linnaeus (1753: 421) (e.g., Hernández-Ledesma et al. 2015, POWO 2022b). On the basis of the protologue and type of Alsine weberbaueri and the current concept in Caryophyllaceae (see e.g., Walters 1993, Chen & Rabeler 2001, Rabeler & Hartmann 2005), this taxon is to be transferred to Arenaria based on the following morphological characteristics: lanceolate-linear leaves without stipules, five free and entire petals, two styles, dehiscent capsules with two teeth, each including 6–10 seeds without strophioles.

Arenaria weberbaueri (Muschl.) Montesinos & Iamonico , comb. nov.

≡ Alsine weberbaueri Muschler (1911: 448) .

Type (neotype, here designated): ― PERU: Junín, Yauli, Morococha , public park, 4195 m, 26 April 2022, Montesinos 9345 ( HOXA080341 !, B101228133 !) ( Fig. 1 ) .

Distribution and ecology:― Arenaria weberbaueri has not been collected in the type locality or nearby areas since its original description in 1911. During a recent expedition in 2022, we found it growing near the town of Morococha, at an altitude of 4195–4500 m a.s.l., inhabiting microhabitats in rocky outcrops, usually growing in stone cracks and crevices on humid montane grasslands with scattered lakes.

Figures

FIGURE 1. Arenaria weberbaueri (HOXA080341!).