Cladosporium marinisedimentum Wonjun Lee & Y.W. Lim, 2023

Lee, Wonjun, Kim, Ji Seon, Seo, Chang Wan, Lee, Jun Won, Kim, Sung Hyun, Cho, Yoonhee & Lim, Young Woon, 2023, Diversity of Cladosporium (Cladosporiales, Cladosporiaceae) species in marine environments and report on five new species, MycoKeys 98, pp. 87-111 : 87

Cladosporium marinisedimentum Wonjun Lee & Y.W. Lim sp. nov.

Figs 2C , 3C

Typification.

Western Pacific Ocean, 15°22.697'N, 151°40.836'E, depth 5730 m, deep-sea sediment, 23 May 2021, Y.J. Kim, Wonjun Lee & Y.W. Lim (holotype SFC20230103-M28, stored in a metabolically inactive state).

Etymology.

The epithet ' marinisedimentum ', derived from Latin, refers to 'marine sediment,' a habitat where the species was isolated.

Description.

Asexual morphology: Mycelium immersed, composed of septate, branched, pale brown or subhyaline, verruculose hyphae, 2.6-4.5 μm wide. Conidiophores macronematous and micronematous, arising laterally or terminally from hyphae, sometimes reduced to conidiogenous cells, septate, erect to slightly flexuous, non-nodulose, branched, up to 220 μm long, 1.5-3.7 μm wide, pale brown, smooth to verruculose. Conidiogenous cells integrated, terminal, rarely intercalary, filiform to cylindrical, 16.2-41.5 × 2-3.2 μm, bearing up to three slightly darkened and refractive conidiogenous loci. Ramoconidia 0-1(-3)-septate, subcylindrical to cylindrical, 9.2-31.8 × 1.7-3.3 μm [av. ( ± SD) 17.4 ( ± 6.07) × 2.6 ( ± 0.34)], pale brown, smooth to verruculose. Conidia forming branched chains, with up to four conidia in the terminal unbranched part, aseptate, pale brown, smooth to verruculose, with protuberant, slightly darkened, and refractive hila. Small terminal conidia aseptate, subglobose to ellipsoidal, 2.6-4.6 × 2.1-3.2 μm [av. ( ± SD) 3.6 ( ± 0.52) × 2.6 ( ± 0.23)]. Intercalary conidia 0(-1)-septate, subglobose to ellipsoidal-limoniform, ovoid, 3.2-9.1 × 2.1-3.6 μm [av. ( ± SD) 4.6 ( ± 1.25) × 2.8 ( ± 0.34)]. Secondary ramoconidia 0-1(-2)-septate, subcylindrical to ellipsoidal, 7.8-31.6 × 2.1-3.4 μm [av. ( ± SD) 13.9 ( ± 4.88) × 2.7 ( ± 0.34)].

Cultural characters: Colonies on PDA 37-46 mm diam after 14 d at 25 °C, olive (2E6 to 3E8), reverse dark gray (1F1), velvety, powdery, radially furrowed, wrinkled, umbonate; margin white edge, slightly lobate; aerial mycelia sparsely formed, without prominent exudates, sporulation profuse. Colonies on MEA 36-43 mm diam after 14 d at 25 °C, olive gray (2D2) to olive (2E3), reverse dark gray (1F1), powdery, velvety, undulate, slightly raised, radially furrowed, wrinkled; margin whitish edge, slightly lobate or undulate; aerial mycelia moderately formed, somewhat irregular, without prominent exudates, sporulation profuse. Colonies on OA 33-37 mm diam after 14 d at 25 °C, olive gray (2E2) to olive (2F3), reverse concolorous, powdery, floccose, flat; margin whitish, regular; aerial mycelia abundantly formed in radial form, without prominent exudates, sporulation profuse. Colonies on SNA 19-23 mm diam after 14 d at 25 °C, olive (2F3 to 2F8), reverse concolorous, powdery, flat; margin yellowish white (1A2), regular; aerial mycelia sparsely formed, without prominent exudates, sporulation profuse.

Habitat and distribution.

Isolated from deep-sea sediments and sea sands; Eastern and Southern Korean seaside in Republic of Korea and Eastern Mariana trench in Western Pacific Ocean.

Additional cultures examined.

Western Pacific Ocean, 16°06′15″N, 152°25′00″E, depth 5814 m, deep-sea sediment, 27 May 2021, Y.J. Kim, Wonjun Lee & Y.W. Lim (MABIK FU00001143, stored in a metabolically inactive state); Republic of Korea. Gangwon-do, Goseong-gun, 38°28′39″N, 128°26′22″E, sea sand, Jul 2021, M.S. Park & Y.W. Lim (SFC20230103-M29, stored in a metabolically inactive state).

Notes.

Cladosporium marinisedimentum sp. nov. is phylogenetically related to C. sphaerospermum . The former species has broader hyphae than the latter one (1-3 μm) ( Bensch et al. 2018), but the conidiophores of C. marinisedimentum are narrower than that of C. sphaerospermum (2.5-4.5(-6) μm) ( Bensch et al. 2018). The number of septa in ramoconidia and secondary ramoconidia in C. marinisedimentum is lower than that in C. sphaerospermum (up to five septa and 0-3(-4)-septate; Bensch et al. 2018). On PDA, C. marinisedimentum does not produce any exudates or pigments, whereas C. sphaerospermum produces prominent exudates and green soluble pigments ( Bensch et al. 2018). Furthermore, the two species differ from each other in the identities of act (98.04%) and tef1 (93.23%) genetic markers (CBS 193.54).

Figures

Figure 2. Morphological characteristics of the new and unrecorded species on PDA, MEA, OA, and SNA media A Cladosporium lagenariiforme sp. nov. B Cladosporium maltirimosum sp. nov. C Cladosporium marinisedimentum sp. nov. D Cladosporium marinum sp. nov. E Cladosporium proteacearum F Cladosporium snafimbriatum sp. nov. " F " and " R " represent the front and the reverse sides of the culture plate, respectively. PDA: potato dextrose agar; MEA: malt extract agar; OA: oatmeal agar; SNA: synthetic nutrient-poor agar.

Figure 3. Morphological characteristics of conidial structures on SNA A Cladosporium lagenariiforme sp. nov. B Cladosporium maltirimosum sp. nov. C Cladosporium marinisedimentum sp. nov. D Cladosporium marinum sp. nov. E Cladosporium proteacearum F Cladosporium snafimbriatum sp. nov. Scale bars: 10 μm (A-F).