Sarcogyne fasciculata K. Knudsen, Kocourk. & Hodkova 2025, sp. nov.

Sarcogyne fasciculata K. Knudsen, Kocourk. & Hodková sp. nov. Fig. 6 Type. U. S. A. • New Mexico, Lincoln Co., Chihuahuan Desert, Tularosa basin, Oscura, near Road 54, 33.4863, - 106.0925, alt. 1475 m, SW-NE oriented crest above the valley, southernmost hill, on northwest facing slope, on acid sandstone outcrop, 17 March 2022, J. Kocourková 10863 (PRM, holotype). Diagnosis. Similar to Sarcogyne nogalensis but becoming squamulose. Etymology. Based on the species forming distinctive fascicles of squamules with interconnected stipes while in the process of splitting apart when replicating by division. Description. Hypothallus endosubstratal, no algae observed. Thallus of squamules or subsquamulose areoles, 0.2–0.5 (– 1.0–2.0) mm wide, 250–500 μm thick, with stipe 50–200 μm high, forming dispersed to contiguous colonies up to 3 × 2 cm, sometimes imbricate, with an uneven`topography, replicating by division. Upper surface light or dark brown, rarely shiny, epruinose, the lobes curling downward around the stipe, smooth or with abscission fissures when beginning to replicate by division, forming fasciculate structures of interconnected stipes of squamules during replication. Lower surface pale white sometimes with an undertone of pale brown, corticate with periclinal hyphae, hyaline, up to 20 μm thick. Epicortex, uneven, ca 10 μm thick. Cortex 20–40 (– 60) μm thick, upper layer ca. 10 μm thick of dark brown round cells, lower layer hyaline of round cells or ellipsoid cells 2–3 × 1.5–2.0 μm. Algal layer 70–120 μm thick, dense, uninterrupted, continuous below apothecia. Medulla obscure, white to pinkish-brown, 100–200 μm thick, hyphae continuous with stipe, 2–4 μm wide, thin-walled, sometimes disarticulated cells expanded or irregular, 4–8 μm wide. Apothecia immersed, darker brown than thallus, in San Bernardino Mountains specimens black, often concave, 0.1–0.6 mm wide, epruinose, occasionally looking pseudolecanorine with squamule reduced to thalline margin, sometimes apothecia in raised parathecial margin. Parathecium up to 60 μm wide, hyphae 2–3 μm wide with apices in brown pigment caps to 5 μm wide, merging with cortex. Hymenium 60–80 (– 120) μm tall, highest in center, epihymenium 10–15 μm tall, light brown, paraphyses 1.5–2.5 μm wide, apices unexpanded in brown gel caps 2–4 μm wide with upper black pigment line, hymenial gel IKI + dark blue bleeding into parathecium and hypothecium. Asci (40 –) 50–75 × 10–20 μm, narrowly cylindrical to inflated clavate, ascospores, 2–4 × 1.5–2.5 µm (n = 20). Subhymenium 20–40 µm tall, IKI + blue. Hypothecium 10–30 µm tall, hyphae 2 µm wide. No pycnidia observed. Chemistry: not producing secondary metabolites. Habitat and distribution. Sarcogyne fasciculata occurs in the Chihuahuan Desert in New Mexico on HCl- sandstone from 1475–1616 m and in southern California on granite in the Little San Bernardino Mountains and the San Bernardino Mountains at elevations 1650–2167 m. Selected specimens examined. U. S. A. • California, Riverside Co., Joshua Tree National Park, Mojave Desert, Little San Bernardino Mountains, Eureka Peak, E and West of the summit, 34.0132, - 116.3502, alt. 1675 m, abundant on granite, 22 Feb 2006, K. Knudsen 5212 (SBBG); • San Bernardino Co., San Bernardino Mountains, conifer forest, above dirt road to Fish Creek, 34.1483, - 116.7720, alt. 2167 m, common on granite boulder, 23 Nov 2014, K. Knudsen 17163 (BRY-C, SBBG). • New Mexico, Lincoln Co., Chihuahuan Desert, Carrizozo, Valley of Fires Recreational Area, Malpais Lava Flow, 33.8300, - 105.9264, alt. 1616 m, on northwest-facing slope above lava flow, on sandstone pebble, 18 March 2022, J. Kocourková 10848 (hb. K & K), • 33.3503, - 105.9227 alt. 1615 m, on northwest-facing slope above lava flow, on sandstone outcrop in full sun, 22 March 2020, J. Kocourková 10974, 10971, 10930 (hb. K & K, SBBG). Notes. Sarcogyne fasciculata was first reported from the San Bernardino Mountains as immature S. squamulosa (Knudsen and McCune 2013; Knudsen et al. 2017). It was assumed in this population the typical apothecia of S. squamulosa had not formed yet. Sarcogyne fasciculata differs from S. squamulosa in not forming elevated brown lecideine apothecia with a parathecium expanded up to 80 µm to form a margin. The apothecia of S. fasciculata remain immersed in the squamule or areole and rarely expand reducing the areole or squamule to a thalline margin. In our current key of Acarosporaceae of southwestern North America Sarcogyne fasciculata is recovered in Section 8, and couplet 9 brown species with euamyloid hymenial gel with S. nogalensis (Knudsen et al. 2023 a). Young specimens of S. fasciculata that are subsquamulose may be confused with S. nogalensis. But Sarcogyne nogalensis remains areolate and does not become stipitate as well as genetically not being closely related (Fig. 1; Knudsen et al. 2023 a).

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.