Gongronella orasabula Hyang B. Lee, K. Voigt, P.M. Kirk & T.T.T. Nguyen, sp. nov.
MycoBank number: MB 814447, Facesoffungi number: FoF 02065, Fig. 3
Etymology – orasabula. Referring to beach soil from which the species was first isolated (Busan, Korea).
Holotype – EML-QF12-1, deposited at the Environmental Microbiology Laboratory Fungarium, Chonnam National University, Gwangju, Korea. Living culture CNUFC-EMLQF12-1, in Chonnam National University Fungal Collection (CNUFC), Gwangju, Korea.

Colonies exhibit fast growth on SMA attaining a diam. of 33 – 35 mm after 5 days at 25 °C, initial colour white, later offwhite, in reverse white with an irregular margin. Sporangiophores 35 – 200 × 2.5 – 4 μm, erect, either unbranched or with 2 – 3 branches. Sporangia 12 – 20 × 12.5 – 22 μm, globose to subglobose or calabash vase – shaped, multi-spored, with a thin wall having a purplish tinge and deliquescent at maturity. Columellae 2 – 3 × 3 – 4 μm, hemisphaerical, with a collarette. Apophysis of diverse shape, globose, subglobose to pyriform, 5 – 10 × 4.5 – 8.5 μm. Sporangiospores mostly bean-shaped, 2 – 3.5 × 2 – 2.5 μm. Chlamydospores absent in aerial mycelia. Zygospores not observed; rhizoids not well developed.

Notes – Gongronella orasabula is morphologically similar to G. koreana, but differs fromrelated species by having larger and differently shaped sporangia. The apophysis is also larger, mainly globose, subglobose or pyriform or rarely long conical. Furthermore, the isolate has two septa below the apophysis.

Material examined – REPUBLIC OF KOREA, Division of Food Technology, Biotechnology & Agrochemistry, College of Agriculture & Life Sciences, Chonnam National University, Gwangju 61186, Korea, from a soil sample collected at Gwangan beach, Busan, Korea; EML-QF12-1 (extype) at Culture Collection of National Institute of Biological Resources (NIBR), Incheon, and preserved as glycerol stock at -80 °C in the CNUFC; living culture (ex-type) deposited at Jena Microbial Resource Collection (University of Jena and Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany) (JMRC:SF:012180).

The isolate was observed to grow over a wide range of temperatures with varying growth rates of 7.3 mm, 6.7 mm, and 6 mm per 24 h on SMA, PDA (potato dextrose agar), and MEA (malt extract agar), respectively. Optimal growth was observed at 27 °C, slow growth was observed at 20 °C, and no growth at 37 °C. Gongronella orasabula appears to be phylogenetically related to G. koreana, both clustering in the same clade together with G. butleri which is the type of the genus Gongronella (Figs. 1, and 2).

Fig. 1 Phylogenetic tree for Gongronella orasabula EMLQF12-1 and EML-QF12-2 based on Maximum likelihood analysis of ITS rDNA sequence. Sequences of Gongronella lacrispora was used as outgroup. Bootstrap support values >50 % are indicated at the nodes. The bar indicates the number of substitutions per position. New taxa are in blue and ex-type strains in bold.

Fig. 2 Phylogenetic tree for Gongronella orasabula EML-QF12-1 and EML-QF12-2 and related species based on Maximum likelihood analysis of multi-genes including 18S and 28S rDNA, actin (Actin-1) and translation elongation factor (EF-1α). Sequences of Umbelopsis nana and U. isabellina were used as outgroups. Bootstrap support values >50 % are indicated at the nodes. The bar indicates the number of substitutions per position.

Fig. 3 Gongronella orasabula (holotype) a, b Colony in synthetic mucor agar (a from above, b reverse view) c – g Mature sporangia with variously shaped apophysis (red arrows) and sporangia h Columellae with collarette and two septa (blue arrows). Scale bars = 20 μm.