Cyathodium cavernarum Kunze

Fernandes, Rozijane Santos, Silva, José Augusto dos Santos, Ottoni, Felipe Polivanov & Pinheiro Costa, Denise, 2021, Diversity of thalloid liverworts in Brazilian Savanna of Parque Nacional da Chapada das Mesas, Maranhão, Brazil, Check List 17 (1), pp. 45-58 : 49

publication ID	https://doi.org/ 10.15560/17.1.45
persistent identifier	https://treatment.plazi.org/id/285C4B08-FFF2-6969-60A8-35FFFC77F975
treatment provided by	Marcus
scientific name	Cyathodium cavernarum Kunze
status

Treatment

Cyathodium cavernarum Kunze View in CoL

Figure 3A–E

Material examined. BRAZIL – Maranhão • Carolina, Parque Nacional Chapada das Mesas, Cachoeira São Romão ; 07°04′25″S, 047°05′26″W; alt. 256 m; 07 Jun. 2018; J. A. S Silva 275 col.; CCAA 1587 GoogleMaps . • ibid., Com- plexo Pedra Caída, cachoeira do Santuário ; 07°02′44″S, 047°27′01″W; alt. 128 m; 07 Feb. 2020; J. A. S Silva 551 col.; CCAA 2696 GoogleMaps .

Identification. Plants rupicolous. Thallus obcuneate, very thin, only 2 or 3 cells wide, with smooth rhizoids, bright green to yellowish, 4–6 × 0.6–1.0 mm, without central midrib; main axis broad and flat; dorsal surface of chlorophyllose thallus with epidermal pores with a ring of 6–8 cells; thallus in cross section with one layer of air chambers without chlorophyllose filaments; ven- tral surface with chlorophyllose cells; margin entire, greenish; ventral scales reduced or absent. Sporophyte on the ventral surface of the thallus (near the apex); involucre sac-shaped; capsule ovoid, dark brown, opening with an operculum; spores spherical and densely spinose, dark brown; elaters long.

Cyathodium cavernarum differs from other spe- cies of thallose liverworts in the study area by having a bright green thallus with few layers of cells, and a sporophyte capsule opening through a ring of cells. It differs

from other species of Cyathodium by having the rhizoids with smooth walls, a sporophyte with an operculum, and spiny spores (Bischler-Causse et al. 2005).

Distribution and ecology. Worldwide (Bischler-Causse et al. 2005 and Söderström et al. 2020). Atlantic Forest (Minas Gerais), Caatinga (Bahia, Ceará, Paraíba, Pernambuco, and Piauí), Brazilian Cerrado (Goiás, Mato Grosso, Maranhão, and São Paulo), Pantanal (Mato Grosso do Sul) ( Söderström et al. 2020; Flora do Brasil 2020; new data). We collected C. cavernarum on shaded rocks with a thin trickle of water running over the gametophyte. It was collected fertile only at the end of the rainy season.

Lepidoziaceae