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

Figs 2D , 3D

Typification.

Republic of Korea. Jeju-do, Chuja-myeon, 33°23′53″N, 126°14′24″E, seaweed, 31 Aug 2021, M.S. Park & Y.W. Lim (holotype SFC20230103-M33, stored in a metabolically inactive state).

Etymology.

The name ' marinum ', derived from Latin, refers to the various marine substrates (seaweed, sea sand, and mudflat) from which the species was isolated.

Description.

Asexual morphology: Mycelium superficial and immersed, composed of septate, branched, hyaline to subhyaline, smooth to verruculose hyphae, nodulose, 2-5.7 μm wide. Conidiophores macronematous and micronematous, arising laterally or terminally from hyphae, (sometimes reduced to conidiogenous cells), septate, slightly flexuous, non-nodulose, usually unbranched or branched, up to 243 μm long, 2-4 μm wide, pale brown, verruculose to verrucose. Conidiogenous cells integrated, terminal and intercalary, cylindrical to subcylindrical, 20.5-47.7 × 2-3.6 μm, bearing up to four slightly darkened and refractive conidiogenous loci. Ramoconidia 0-1(-2)-septate, subcylindrical to cylindrical, 10.2-28.171 × 2.4-4.1 μm [av. ( ± SD) 17.3 ( ± 2.39) × 2.9 ( ± 0.37)], pale brown, verruculose. Conidia forming branched chains, with up to five conidia in the terminal unbranched part, long neck area between conidia, aseptate, pale brown, smooth to verruculose, with protuberant, slightly darkened and refractive hila. Small terminal conidia aseptate, obovoidal to ellipsoidal, 2.9-5.3 × 2-3 μm [av. ( ± SD) 3.8 ( ± 0.53) × 2.5 ( ± 0.25)]. Intercalary conidia aseptate, very rarely 1-septate, ellipsoidal to limoniform, obovoid, sometimes subcylindrical, 2.7-6.2 × 1.8-2.8 μm [av. ( ± SD) 4.2 ( ± 0.76) × 2.3 ( ± 0.22)]. Secondary ramoconidia 0-1-septate, subcylindrical to cylindrical, slightly obclavate, 8.5-28.2 × 2.3-3.7 μm [av. ( ± SD) 14.5 ( ± 4.38) × 2.9 ( ± 0.35)].

Cultural characters: Colonies on PDA 37-66 mm diam after 14 d at 25 °C, olive (3E3 to 3F4), reverse dark gray (1F1), floccose-velvety, sometimes woolly, raised, radially furrowed, wrinkled, raised; margin white, slightly hyaline edge, undulated; aerial mycelia abundantly formed, with numerous prominent exudates, sporulation profuse. Colonies on MEA 35-40 mm diam after 14 d at 25 °C, grayish white (1B1) to olive gray (3D2), reverse dark gray (1F1), velvety, raised to crateriform, radially furrowed at the margin region, wrinkled; margin white, regular; aerial mycelia abundantly formed, dense, without prominent exudates, sporulation profuse. Colonies on OA 41-47 mm diam after 14 d at 25 °C, gray (1C1 to 1E1), reverse concolorous, velvety, floccose, raised, radially furrowed; margin yellowish, regular; aerial mycelia abundantly formed, with few exudates, sporulation profuse. Colonies on SNA 37-41 mm diam after 14 d at 25 °C, olive (3D3) to olive yellow (3E8), reverse olive (3D3 to 3F3), slightly fluffy-floccose, powdery, flat; margin yellowish white (2A2), hyaline, undulate; aerial mycelia abundantly moderate, without prominent exudates, sporulation profuse.

Habitat and distribution.

Isolated from mudflats, sea sands, and seaweeds; Southern and Western Korean seaside in Republic of Korea.

Additional cultures examined.

Republic of Korea. Jeju-do, Chuja-myeon, 33°23′53″N, 126°14′24″E, seaweed, 31 Aug 2021, M.S. Park & Y.W. Lim (SFC20230103-M30, stored in a metabolically inactive state); Jeju-do, Chuja-myeon, 33°23′53″N, 126°14′24″E, seaweed, 31 Aug 2021, M.S. Park & Y.W. Lim (SFC20230103-M31, stored in a metabolically inactive state); Jeju-do, Chuja-myeon, 33°23′53″N, 126°14′24″E, seaweed, 31 Aug 2021, M.S. Park & Y.W. Lim (SFC20230103-M32, stored in a metabolically inactive state); Jeju-do, Chuja-myeon, 33°57′50″N, 126°17′38″E, seaweed, 31 Aug 2021, M.S. Park & Y.W. Lim (SFC20230103-M34, stored in a metabolically inactive state); Jeju-do, Hallim-eup, 33°23′53″N, 126°14′24″E, seaweed, 15 Aug 2021, M.S. Park & Y.W. Lim (SFC20230103-M35, stored in a metabolically inactive state); Jeju-do, Hallim-eup, 33°23′53″N, 126°14′24″E, seaweed, 15 Aug 2021, M.S. Park & Y.W. Lim (SFC20230103-M36, stored in a metabolically inactive state); Jeollanam-do, Muan-gun, 35°01′40″N, 126°25′16″E, mudflat, Apr 2017, M.S. Park & Y.W. Lim (SFC20230103-M37, stored in a metabolically inactive state); Jeollanam-do, Muan-gun, 35°03′44″N, 126°20′13″E, sea sand, Oct 2016, M.S. Park & Y.W. Lim (SFC20230103-M38, stored in a metabolically inactive state); Jeollanam-do, Suncheon-si, 34°50′29″N, 127°29′09″E, sea sand, Jul 2020, M.S. Park & Y.W. Lim (SFC20230103-M39, stored in a metabolically inactive state); Jeju-do, Seogwipo-si, 33°13′58″N, 126°18′47″E, sea sand, Jan 2021, M.S. Park & Y.W. Lim (SFC20230103-M40, stored in a metabolically inactive state).

Notes.

Cladosporium marinum sp. nov. forms an independent clade in the phylogenetic tree of the C. cladosporioides species complex (Fig. 1 ), but it has no distinguishable characteristics compared to those of the other species. Molecular and phylogenetic approaches are imperative to identify and differentiate this species from other species.

Figures

Figure 1. Maximum likelihood (ML) tree of Cladosporium, inferred based on ITS, act, and tef 1 sequences. The values at each node indicate the bootstrap of ML (≥ 70) and the posterior probability (PP; ≥ 0.90) of Bayesian inference (BI) analyses. Thick lines on branches indicate 100 bootstrap and 1.00 PP support. The tree is rooted to Cercospora beticola (CBS 116456). The small tree on the upper left represents the topology of species complexes of the genus. The filled triangles correspond to the species complex (es) shown. The colored circles symbolize habitats where the species were isolated. Previously described species are grouped in gray boxes, and blue boxes indicate new species. Strains with newly generated sequences are in red, with the holotypes in bold. The holotype and epitype for the reference strains are represented with " * " and " ** ", respectively.

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).