Orthotrichum camanchacanum Plášek, Sawicki & Osorio, 2024

Plášek, Vítězslav, Sawicki, Jakub, Osorio, Felipe, Szczecińska, Monika & Režnarová, Hana, 2024, Orthotrichum camanchacanum, a remarkable new moss species from Chile (Bryopsida, Orthotrichaceae), PhytoKeys 242, pp. 51-67 : 51-67

Orthotrichum camanchacanum Plášek, Sawicki & Osorio sp. nov.

Diagnosis.

Plantae olivacea, obscure viridis, usque ad 1 - cm altae. Folia erecta, lineari-lanceolata, carinata, apicibus longis acuminatis. Capsulae emergentes, cylindricae. Stomata cryptopora. Vaginula dense pilosa cum capilli longi. Peristomium duplex, exostoma 8 paribus dentium siccitate erectum, endostoma 16 segmentis. Calyptra dense pilosa. Sporae 19–24 µm, leniter papillosae.

Type.

Chile, Región de Coquimbo (Region IV), Provincia del Elqui, Comuna de Coquimbo , 2 km southeast of Totoralillo town, GPS: 30 ° 04 ' 26 " S, 71 ° 21 ' 13 " W (- 30.073972, - 71.353583), on hills profoundly influenced by the humidity generated by camanchaca, vegetation formed mainly by shrubs ( Adesmia argyrophylla Phil. and Echinopsis chiloensis subsp. chiloensis (Colla) H. Friedrich & G. D. Rowley ), moss was found epiphytically on bark of shrubs, leg. F. Osorio 4378, 10 Aug 2021, holotype ( OSTR # 8123 ); isotype ( VALD s. n.) .

Description.

Plants in dense tufts to 1 cm tall, olive green above, dark green to brown below (Fig. 2 ). Stem moderately branched, branches up to 5 mm long. Rhizoids well developed, mainly at base of stems. Stem leaves erect to slightly recurved when dry, spreading to slightly recurved when moist; in upper third linear-lanceolate, long acuminate, 3.0–4.1 × 0.3–0.5 mm, carinate; costa ending just below apex or more often excurrent in hyaline long arista. Leaves in the middle and lower part of the stem wider and shorter, ovate-lanceolate, acuminate, 3.0–3.6 × 0.4–0.7 mm, carinate; costa ending just below apex or rarely excurrent in short aristae. Lamina of stem leaves unistratose, margins entire, recurved from the base to two-thirds of the leaf. Hyaline aristae rectangular, formed by (1 –) 2–3 gradually elongating cells, from 50–65 to 90–115 × 8–10 µm. Upper laminal cells isodiametric to short elongate, (9 –) 10–15 × 8–11 µm, fairly thick-walled, with one low papillae on both side; basal laminal cells elongate rectangular to rhomboidal, thick-walled, (18 –) 20–45 × 10–12 µm, smooth. Alar cells slightly differentiated. Sexual condition goniautoicous. Perichaetial leaves differentiated, ovate-lanceolate, acuminate, significantly shorter than stem leaves, only 1.7–2.2 × 0.5–0.8 mm; upper cells forming conspicuous hyaline (sometimes denticulate) apex (Fig. 3 ). Seta 1.1–1.5 mm long, ochrea up to 1 / 5 of the seta, vaginula densely hairy with 0.8–1.9 mm long, single-rowed or sometimes double-rowed, smooth hairs, which usually reach the base of the urn (Fig. 4 ). Capsule emergent; cylindric to oblong-ovoid, about 1.8–2.2 mm long, yellowish brown, slightly constricted below the mouth when dry. Exothecial cells differentiated mainly in the upper half of capsule, urn strongly furrowed when dry. Stomata cryptopore, scattered in the lower part of the urn, more than half covered by subsidiary cells. Peristome double (Figs 4 , 5 ), preperistome absent. Exostome of 8 pairs of teeth, yellow to light brown, erect-spreading when dry. The outer peristome layer ( OPL) ornamentation formed by dense papillae below and a mixture of papillae and distinct striae above. The primary peristome layer ( PPL) finely and evenly ornamented by vermiculous lines, slightly also with low papillae. Endostome segments 16, almost as tall as exostome, reflexed when dry; 8 main segments double-rowed and 8 intermediate thinner, single-rowed, somewhat shorter or completely broken in matured capsules. The inner peristome layer ( IPL) smooth or ornamented indistinctly by vermiculous lines in the lower part. Calyptra conic-oblong, more or less plicate, yellowish with longitudinal brown stripes, apex red-brown, densely hairy with long, yellowish, smooth hairs. Lid conic, apiculate. Spores light brown, 19–24 µm, densely papillose. Asexual reproduction not observed.

Distribution and ecology.

Moss Orthotrichum camanchacanum was discovered growing epiphytically on the bark of shrubs within vegetation predominantly composed of shrubs such as Adesmia argyrophylla and Echinopsis chiloensis subsp. chiloensis . This epiphytic growth pattern suggests a specific ecological niche for this moss within the ecosystem. See map (Fig. 1 ) for a visual representation of the study area. The territory under investigation lies within the Coquimbo region, characterized by numerous transverse valleys. Notably, the Elqui valley, where Orthotrichum camanchacanum was observed, is situated within this region. The environmental conditions in the study area are influenced by the Andes mountain range, contributing to a steppe-like climate. This climate is typified by sparse vegetation, consisting primarily of shrubs and scrubby vegetation. Precipitation, the heaviest of which occurs during the winter months, further shapes the ecological dynamics of the region.

Etymology.

The authors are delighted to name the species (camanchacanum) after “ camanchaca ”, a term derived from Aymara native language, signifying marine cloud (fog). Forming along the Chilean coast as a cloud, the camanchaca transforms into a dense fog as it moves inland towards the mountains. This fog provides the humidity essential for plant survival.

Figures

Figure 1. The map illustrates the geographical location where Orthotrichum camanchacanum was discovered.

Figure 2. Macro photographs of Orthotrichum camanchacanum. View on fertile plants: A plants with capsules at various stages of development: young immature capsule (left), capsule closed by lid (middle), and mature capsule with open peristome (right) B dried furrowed capsules emergent from long leaves. Scale bars: 1 mm (A, B). Photographs were taken from the holotype (OSTR # 8123).

Figure 3. Micro photographs of Orthotrichum camanchacanum leaves A – G leaves from upper part of a stem (linear-lanceolate with remarkable narrow hyaline apex) H – N leaves from middle and lower part of a stem (many of them are damaged and without apical part) O – S detail views of laminar cells, abaxial views (O apical part P upper part Q middle part R lower part and S base of leaf) T – V perichaetial leaves W leaf sections (from apical to basal part). Scale bars: 1 mm (A – N); 100 µm (O – S); 0.5 mm (T – V); 50 µm (W). Photographs were taken from the holotype (OSTR # 8123).

Figure 4. Macro and micro photographs of Orthotrichum camanchacanum sporophyte characters A, B view on mature capsules C, D mature capsule with peristome E detail of peristome F stoma (immersed) on capsule urn G lid H, I spores J, K calyptra covered by long hairs L, M hairy vaginula. Scale bars: 1 mm (A, B); 0.5 mm (C, D); 100 µm (E); 50 µm (F); 0.1 mm (G); 20 µm (H, I); 0.5 mm (J – M). Photographs were taken from the holotype (OSTR # 8123).

Figure 5. SEM photographs of Orthotrichum camanchacanum A capsule B double peristome C – E detailed view on exostome teeth and endostome segments F spores. Scale bars: 500 µm (A); 100 µm (B); 50 µm (C – E); 20 µm (F). Photographs were taken from the holotype (OSTR # 8123).