Andrewsianthus australis var. verrucosus Mamontov, 2022

Mamontov, Yu. S., 2022, Andrewsianthus australis var. Verrucosus var. nov. (Lophoziaceae, Marchantiophyta) from Chile, Arctoa 31 (2), pp. 181-184 : 182-183

Andrewsianthus australis var. verrucosus Mamontov , var. nov. Fig. 1 , 2.

Type: CHILE, Aysén Region, Aysén Province, Cisnes Commune, Parque Nacional Queulat, Salto el Condor Waterfall near Carretera Austral, 44°38'34.3" S ,

72°26'28.5" W, 326 m a.s.l., 30.XI.2021, Mamontov & Shkurko 934-6-7484 ( MHA – holotype) .

Etymology. The name reflects the coarsely verrucose surface of leaves in the new variety.

Diagnosis. Plants golden brown, small, with flagelliform shoots arising mostly from the ultimate branches, with leaves ca. 1.32–1.46× as long as wide, 0.17–0.28 divided into two unequal to subequal lobes, with leaf cells cuticle coarsely verrucose (covered with round to elliptic papillae), with underleaves rudimentary, composed of several cells or 2–3 slime papillae.

Description. Plants intermixed with other liverworts, main axes mostly suberect, usually not becoming flagelliform, sterile shoots up to 7 mm long, 0.5–0.7 mm wide, mostly golden brown. Branches sparing, lateral-intercalary, arising from the dorsal end of the leaf axil and of the Andrewsianthus - type, occasionally appearing from the leaf axil and thus perceptibly lateral, sometimes initially suberect and then becoming arched, sometimes flagelliform, the flagelliform axes with rhizoids and scale-like leaves, sometimes becoming leafy, rarely positively geotropic. Stems 90–140 µm thick, dark brown when dry, in surface view the cortical cells rounded-quadrate to rectangular, 39–82 µm long, 33–56 µm wide, thin- to thick-walled, cuticle smooth to striate. Rhizoids sparing, mostly grouped in fascicles from stem near ventral base of leaf. Leaves 380–620 µm long, (180–)240–440 µm wide, ca. 1.32–1.46 × as long as wide, leaves transverse to weakly succubously inserted and oriented, slightly to distinctly decurrent dorsally, obliquely to laterally spreading, only exceptionally with distal ˝ distinctly recurved, more or less distant, plane to deeply concave, elliptic to ovate, dorsal margin sometimes with a tooth of 1–6 cells near the base ( Fig. 1A , 2A, B), leaves 0.17–0.28 bilobed, lobes triangular, unequal to subequal in size, apices mostly acute, rarely obtuse, the sinus acute- to almost right-angled, occasionally narrowly rounded at base, the leaf margins plane. Leaf cells rounded-quadrate, rounded-rectangular or rounded-polygonal, wall thin, trigones concave to convex and nodulose, occasionally confluent, medi- an leaf cells 20–33 µm long, 14–24 µm wide, marginal cells somewhat smaller, 15–22 µm long, 12–18 µm wide, cuticle covered with round to elliptic papillae, thus coarsely verrucose ( Fig. 2G–I), the papillae 7–21 µm long, 5–11 µm wide. Underleaves rudimentary, composed of several cells or 2–3 slime papillae. Gemmae absent. Plants apparently dioecious (only gynoecia have been found); the unfertilized gynoecia terminal on main axes, with subfloral innovations, the bracts similar in shape to the sterile leaves, but somewhat larger, with entire margins. Bracteole narrowly ovate, entire margined, apex acute.

Ecology and Distribution. The new variety is known only from a single locality in Southern Chile, where it was collected in a gorge with a high waterfall at Salto el Condor. The plants of A. australis var. verrucosus occur on rock outcrops moistened by water drops and spray from the waterfall and were found intermingled in patches of a species of Lejeuneoideae, with an admixture of Lepicolea ochroleuca (Spreng.) Spruce , Hymenophyton pedicellatum Steph. and Temnoma quadripartitum (Hook.) Mitt.

Studied specimens (paratypes). CHILE, Aysén Region, Aysén Province, Cisnes Commune, Parque Nacional Queulat, Salto el Condor Waterfall near Carretera Austral , 44°38'34.3" S, 72°26'28.5" W, 326 m a.s.l., 30.XI.2021, Mamontov & Shkurko 934-6-7483, 934-6- 7485 ( MHA) .

Figures

Fig. 1. Andrewsianthus australis var. verrucosus (from holotype): A, C, D: sterile shoot fragments (dorsal aspect); B: female shoot fragment (dorsal aspect). Scale bar: 1 mm for A–D.