Leptogium microcarpum Malme (1924: 15)

Kitaura, Marcos J., Bernardo, Caique M., Koch, Natália M., Rodrigues, Andressa S., Torres, Jean-Marc, Barbosa, Thiago D., Canêz, Luciana Da S., Spielmann, Adriano A., Honda, Neli K., Fleig, Mariana & Lorenz, Aline P., 2019, Leptogium (Collemataceae, Peltigerales) from Mato Grosso do Sul state, Brazil: nine new records, three new taxa and a key for the species, Phytotaxa 399 (2), pp. 127-146 : 137-139

Leptogium microcarpum Malme (1924: 15) . ( Figure 3B )

Syntypes:— PARAGUAY. Colonia Risso: pr. Rio Apa, corticola in silva clara, 28 September 1893, G.O.A. Malme 1862 Db (S, UPS!). Description: Malme (1924) and Kitaura (2012).

Notes: Leptogium microcarpum is characterized by its ridged surface, with apothecia and pycnidia on the margin of the lobes.

The material Malme 1862 Db was mentioned in the protologue as type ( Malme 1924), but one specimen was found in herbarium S and another in UPS. Both were considered as a single gathering according to McNeill (2014). The specimen in S has not yet been revised and a lectotype has not been selected.

Leptogium species usually have a proper exciple composed by thick paraplectenchymatous tissue or a thalline exciple composed by thick cortex of paraplectenchymatous tissue. However, L. microcarpum is an exception and the thick paraplectenchymatous tissue is not present, neither in the proper exciple nor in thalline exciple. The hypothecium is the tissue that supports the apothecia structures, keeping the integrity after dehydration and hydration processes (Kitaura 2012).

The species was originally described to Paraguay ( Malme 1924) and it can occur in the central part of South America, East of Paraguay and Central-West Region from Brazil, distributed in the Chaco , cerrado and Pantanal habitats.

Distribution: First record to Brazil. It was previously reported to Paraguay, the type locality ( Malme 1924).

Examined material: BRAZIL, Mato Grosso do Sul: Alcinópolis, Monumento Natural Serra do Bom Jardim , trail to Monumento Natural , Gruta da Paca , 18°06’46.2”S, 53°40’04.8”W 624 m elev., 18 October 2017, A.S. Rodrigues, D. R. Fonseca, M.H. Silva 436 ( CGMS 64598 ) ; 437 ( CGMS 64599 ) ; 446 ( CGMS 64608 ) ; PENT, 22 October 2017, M.J. Kitaura 4295 ( CGMS) ; 4297 (CGMS); Aquidauana , ± 30 km of city entrance, on cortex, 07 February 1989, I. Riquelme 080 (No. EQL 0075, CGMS) ; I. Riquelme 080A ( No. EQL 0076, CGMS) ; Campo Grande, Vila da Base Aérea , on cortex, 13 February 1991, I. Riquelme 277 (No. EQL 0448, CGMS) ; 280 ( No. EQL 0451, CGMS) ; Piraputanga district , MS 450, 20°29’52.40”S 55°26’09.00”W 218 m elev., on cortex, 28 November 2014, A.L. Simal, B.A. Coutinho, P.P. Vaz, V. H.S. Brito, A.A. Spielmann 189 ( CGMS 46842 ) ; Jaraguari, Furnas do Dionísio , 20°09’00.5”S 54°34’28.2”W, 440 m elev., 13 November 2015, C.M. Bernardo, T. D. Barbosa 809 .

Figures

FIGURE 3. A–B. Leptogium species. A. L. marginellum (AA Spielmann 8367). B. L. microcarpum (AL Simal 188). C. L. milligranum (SR Ramalho 44). D–F. Leptogium moluccanum var. denticulatum (CM Bernardo 465). D. Detail of the thallus. E. Transversal section of the thallus, arrows = columnar hyphae. F. Transversal section of the apothecia, arrow = subparaplectenchymatous parahymenium tissue. Bars: 2 mm (A–D); 50 μm (E); 100 μm (F).