Myxomycetes in Brazilian mangroves: species associated with Avicennia nitida, Laguncularia racemosa and Rhizophora mangle

Abstract

Background: Mangroves are distributed among tropical and subtropical coastlines of all oceans, and associated macroflora and macrofauna are generally well studied. However, information on mangrove-associated microbiota is still scarce. To help fill this gap in knowledge, we conducted research on the occurrence of Myxomycetes in the southern coast of Pernambuco state, northeastern Brazil. In the Rio Formoso estuary, we examined adult Rhizophora mangle (Rm), Laguncularia racemosa (Lr) and Avicennia nitida (An), collecting samples of live trunk bark (Bk), twigs from aerial litter (Tg), and aerial leaf litter (Lf) for moist chamber culture (n = 600). Results: The following species were identified: Arcyria cinerea (Rm/Tg); A. pomiformis (Rm;Lr/Bk); Collaria arcyrionema (Rm/B); Clastoderma debaryanum (Lr/Bk; Rm/Tg); Cribraria violacea (Rm/Bk;Tg); Physarum auriscalpium (Rm/Tg); P. tenerum (Rm/Bk); Stemonitis fusca (Lr/Tg); S. herbatica (Rm/Lf); S. virginiensis (Rm/Tg) and Stemonaria irregularis (An/Lf). The percentage of positive cultures was very low (24 %), with Rm as the predominant substrate with eight species and Tg as the predominant microhabitat. The majority of species are rare (60 %) and Physarum auriscalpium was the only species frequently registered. The taxonomic diversity indices ranged from 1.00 (Lf;Bk) to 1.20 (Tg). Conclusions: There was no similarity in the composition of myxobiota found on the substrates and microhabitats analyzed. Only S. irregularis was found in mangroves that inhabit areas of higher salinity. Physarum tenerum is reported here for the first time in the mangrove environment.

Myxomycetes of the Atlantic Rainforest: species on the ground litter from Pedra Talhada Biological Reserve (Alagoas, Brazil)

“…Studies on the myxobiota of Atlantic Rainforest and associated ecosystems have been carried out in different phytophysiognomies and microhabitats. They have explored Conservation Units, mainly in the Northeastern region of the country, with records for species in Open Ombrophilous Forest and Seasonal Semideciduous Forest (Cavalcanti et al 2006;Bezerra et al 2007Bezerra et al , 2008Tenório et al 2009), Seasonal Semideciduous Forest and montane humid forest in Open Ombrophilous Forest (Silva & Cavalcanti 2012;Costa et al 2014), Dense Ombrophilous Forest (Xavier de Lima & Cavalcanti 2015), sandbanks (Bezerra et al 2011), andmangroves (Agra et al 2015;Cavalcanti et al 2016;Barbosa & Cavalcanti 2020). Among the microhabitats explored, ground litter has been included in a few studies, such as that carried out by Coelho & Cavalcanti (2010) who registered 30 species distributed in ten families from moist chamber cultures and field collections in two lowland dense rainforest Conservation Units.…”