Arenaria pallens Muschl., Botanische Jahrbuecher fuer Systematik, Pflanzengeschichte und Pflanzengeographie 45(4): 450-451. 1911.

Montesinos-Tubee, Daniel B. & Iamonico, Duilio, 2023, Neotypification for five names linked to Arenaria (Caryophyllaceae) for the endemic flora of Peru and Bolivia, PhytoKeys 230, pp. 131-144 : 131

Arenaria pallens Muschl., Botanische Jahrbuecher fuer Systematik, Pflanzengeschichte und Pflanzengeographie 45(4): 450-451. 1911.

Neotype

(designated here). Peru. Huánuco: Lauricocha, Jesús, Abra Tocana, 4195 m, 03 Aug 2016, D. Montesinos 4902 (B-100766251!, Fig. 3 ).

Muschler (1911: 450-451) validly published the name Arenaria pallens , giving a detailed description, as well as the citation of a syntype (Art. 9.6 of ICN), i.e., "Peru: ad viam ferream inter oppida Lima et Oroya ad hacienda Arapa prope Yauli, ad rupes, in 4400 m altitudine" (Weberbauer 267). -Specimina florigera fructiferaque 18-27 Januarii 1902 - Herb. Berol. [Herbarium Berolinensis, B]". According to Hiepko (1987), the only known collection at B was destroyed. Consequently, lacking original material (Art. 9.3 of ICN), a neotypification is required. The analysis of two specimens stored at B revealed them as alternative material from near the type locality, which is here chosen as neotypes. Note that Muschler’s taxon is a member of Arenaria sect. Dicranilla which has the characteristic ciliate leaf margins and bisexual flowers (see also Timaná, 2017) as typical for A. pallens . We here designate a collection made by one of the authors (DBMT) as the neotype of Muschler’s A. pallens . The species is considered narrowly endemic and was designated as Critically Endangered by Cano and Sánchez (2006). The finding of the species in the Huánuco department expands its distribution and it can be considered to occur in the Pasco department as well and Junín department as first established by Cano and Sánchez (2006).

Further analysis needs to be made for three species described by Muschler (1911) which were not found at the explored localities, in addition to the lack of herbarium material, types destroyed and doubtful protologues. It is concluded that Muschler (1911) described the taxa with an apparent mixture of characters ( Ryding 1939) as seem to occur in Arenaria horizontalis (Muschl.) Molinari (= Pycnophyllum horizontale Muschl.), due to impossible character symmetry as described on page 449, a fact that was not corrected by Molinari (2016).

Description.

Diffuse herb, with branches of about 2-8 cm long, more or less angled and pubescent near the nodes but glabrous in mid-sections; internodes of about 6-10 mm long; leaves linear to linear-lanceolate, rarely ovate-lanceolate, thick or fleshy, with acuminate apex bearing a mucronate tip, base petiolate, lamina of about 5-10 mm long × 1.0-3.0(-3.5) mm width, bearing trichomes at the base, margins and apex; pedicels filiform, densely pubescent or rarely glabrous, less than 1 cm long, curved when fruiting; sepals ovate-oblong, carinate, apex acuminate, hirsute or puberulent along the margins, 3-4 mm long; petals tending to be shorter than the sepals, ovate-oblong and obtuse; anthers pale yellow; styles 3; capsule longer than the calyx; 8 seeds, shiny and smooth.

Specimens examined.

Peru. Huánuco: Huamalies, Singa , W of Bellas Flores, 3601 m, 26 jul 2016, D. Montesinos 4853 (B-1007613519!) .

Figures

Figure 3. Neotype of Arenaria pallens Muschl. (D. Montesinos 4902, B 100766251).