Mucor circinatus D.X. Lima, G. Walther & A.L. Santiago, 2017

Lima, Diogo X., Souza-Motta, Cristina M., Wagner, Lysett, Voigt, Kerstin, De Souza, Carlos A. F., De Oliveira, Rafael J. V., Da Silva, Gladstone A., De Azevedo Santiago, André L. C. M. & Walther, Grit, 2017, Circinella simplex-a misapplied name of Mucor circinatus sp. nov., Phytotaxa 329 (3), pp. 269-276 : 271-273

Mucor circinatus D.X. Lima, G. Walther & A.L. Santiago , sp. nov.

Index fungorum number: IF551671;

Holotype: URM 90063 ( Herbarium URM), Brazil, January 2017, deposited by D. X. Lima. The ex type strain was deposited as URM 7218 in the Culture Collection (Micoteca URM) of Federal University of Pernambuco, Brazil and as JMRC:SF: 012298 in the Jena Microbial Resource Collection ( JMRC at the Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany).

Colony initially white and then becoming yellow brown ( MP 13D1), covering the entire Petri dish (9 cm diam. × 0.5 cm in height) in four days; reverse cream ( MP 13K3). Odorless. Sporangiophores recurved, sympodially branched, width 2.5–12.5 (–18) μm diam. hyaline, slightly rough-walled, growing directly from the substrate, usually with a septum below the sporangium; circinate sympodial branches often arising in the curvature of the previous branch next to the septum. Sporangia initially light yellow then becoming brown, globular and smooth-walled, not deliquescent, breaking, (17.5–) 20 × 35.75 (–56.25) μm diam. Columellae smooth-walled, hyaline, frequently globose to applanate (12.5–) 17.5 × 28.75 (–43) μm diam. Collar evident. Sporangiospores angular (3.8–) 5 × 6.2 (–7.5) μm, hyaline, smooth-walled. Rhizoids-like filaments observed. Chlamydospores barrel shaped to cylindrical. Zygospores not observed. Probably heterothallic. Reduced growth (5.3 cm in 9 days) and sporulation at 12°C, optimal growth at 25°C (9 cm in 4 days); maximal growth temperature 30°C; similar growth on MEA and PDA at all temperatures, slightly better sporulation on MEA. Influence of light: not detected.

Habitat: soil

Distribution: Brazil ( Zycha 1935; Schoenlein-Crusius et al. 2006; de Souza et al. 2011), Colombia ( Gualdrón-Arenas et al. 1997) and Sri Lanka (Peries et al. 1976).

Specimen examined: BRAZIL, Pernambuco, Tamandaré, Saltinho Biological Reserve (8º43’09’’S 35º10’11’’W), soil., 2013, D.X. Lima (URM 90063).

Other examined specimens: CBS 142.35, CBS 284.92, CBS 428.80, CBS 540.80, CBS 548.89.

Notes: Mucor circinatus differs from other Mucor species by its circinate sporangiophores and the angular sporangiospores. The strains described by Hesseltine & Fennel (1955) as Circinella simplex belong in fact to M. circinatus .