Mucor cheongyangensis Hyang B. Lee & T.T.T. Nguyen, 2020

Nguyen, Thuong T. T. & Lee, Hyang Burm, 2020, Mucor cheongyangensis, a new species isolated from the surface of Lycorma delicatula in Korea, Phytotaxa 446 (1), pp. 33-42 : 37-39

Mucor cheongyangensis Hyang B. Lee & T.T.T. Nguyen sp. nov. ( Fig. 3 ).

Index Fungorum number: IF556879

Etymology: Referring to its collection location, Cheongyang is where the species was first isolated (Chungnam Province, Republic of Korea).

Description: Colonies on PDA, cottony, light to moderate orange yellow (7. 1YR), reaching 70‒75 mm diameter after 4 days of incubation at 25°C; reverse light yellow (2. 4Y) ( Rayner 1970). Sporangiophores simple or with 1 or 2 short branches, smooth-walled, with or without yellowish contents, arising directly from the substrate; two septa sometimes present below the columella. Sporangia globose and multi-spored, 24.5–125 × 23.5–120 µm, initially light yellow then darker yellow, smooth-walled, with deliquescent walls. Columellae globose to subglobose, or obovoid, 25–52.5 (–60.5) × 23.5–51.5 (–56.5) µm; containing yellow lipid droplets, and with well-defined collars. Sporangiospores from primary sporangia oval (7.5–14.0 × 5.0–8.5 µm), those from secondary sporangia spherical to subspherical, 7.5–11.5 × 7.0–9.5 µm, with or without greenish granular contents. Chlamydospores abundantly and oidia-like, thick-walled, terminal or intercalary, and single or in chains of up to 27, globose to subglobose, (10.5–18.5 × 10.0–17.5 µm), or barrel-shaped to irregular (21.5–40.5 × 12.0–15.5 µm). Rhizoids present on vegetative hyphae. Zygospores not observed.

The colony characteristics of this fungus when grown on SMA were similar to those observed when grown on PDA; on MEA, this fungus forms a thin growth with very sparse aerial mycelium. The optimum growth temperature was 25–30°C, and the minimum growth temperature was 5°C. At 37°C, growth and sporulation was observed on MEA media, while no growth was observed on PDA and SMA. The fungus did not grow at 40°C.

Material examined: REPUBLIC OF KOREA, house garden located on a hill of Kunryang-ri (36°44’00.2”N 126°78’18.0”E), Cheongyang-eup, Cheongyang, Chungnam Province, from the surface of L. delicatula , 9 July 2019, collected by H.B. Lee (CNUFC HT1912, holotype, ex-type living culture CNUFC ICL1).

Figures

FIGURE 3. Morphology of Mucor cheongyangensis.A, Lycorma delicatula 4th instar. B, Colony on potato dextrose agar (PDA).C, Colony on synthetic agar mucor (SMA). D, Colony on malt extract agar (MEA). E, Simple sporangiophore. F‒H, Sporangia and sporangiospores. I, Sporangiospores. J, Columella. K, Sporangiophore with short branch and two septa below the columella. L, Chlamydospores. M, Rhizoids. N, O, Vesicle exhibiting secondary sporangium. P, Secondary sporangium with deliquescent wall. Scale bars = 20 μm.