Neocamarosporium halocnemi Safi & M. Mehrabi-Koushki, 2025

Safi, Atena, Mehrabi-Koushki, Mehdi & Arzanlou, Mahdi, 2025, New species of Neocamarosporium from two halophyte plants in Iran, Phytotaxa 696 (2), pp. 101-116 : 108-109

Neocamarosporium halocnemi Safi & M. Mehrabi-Koushki , sp. nov. ( Fig. 2 )

MycoBank: MB 856826

Holotype: Iran, Khuzestan Province, Shadegan, isolated from Halocnemum strobilaceum ( Chenopodiaceae ), Dec. 2022, A. Safi (holotype, IRAN 18643 F); ex-types, IRAN 5255 C = SCUA-Saf-p8).

Etymology: The name refers to the host genus Halocnemum from which it was isolated.

Morphology on PDA: Conidiomata pycnidial, superficial or semi-immersed, solitary, globose to sub-globose, dark brown to black, ostiolate, with some hyphal outgrowths, sometimes with 1–2 short necks, 218.3–518.8(–556.2) × 220–451(–486.4) µm; 95% confidence limits = 369.3–416.4 × 317.2–350.4 µm, (x̄ ± SD = 392.8 ± 82.8 × 333.8 ± 58.5 µm, n = 50). Ostioles 1–2, non-papillate. Pycnidial wall pseudoparenchymatous, 4–6 layers thick, outer layers composed of more or less textura angula ris to prismatica, brown to black, outer layers darker. Conidiophores are reduced to conidiogenous cells. Conidiogenous cells hyaline, solitary, doliiform, enteroblastic, annellidic, integrated, smooth-walled, 4.1–9 × 2.7–9.4(–10.1) µm; 95% confidence limits = 5.8–6.9 × 5.4–6.7 µm, (x̄ ± SD = 6.4 ± 1.4 × 6 ± 1.8 µm, n = 30). Conidia amerosporous, didymosporous, phragmosporous or dictyosporous, with longitudinal and/or transverse septa, pale brown to brown, smooth-walled, variable in shape, subglobose to ellipsoid, fusiform or oblong; subglobose to ellipsoid conidia (7.6–)8.8–13.9(–18.4) × 5.3–7.8 µm, 95% confidence limits = 10.5–11.5 × 6.7–7.01 µm, (x̄ ± SD = 11 ± 1.7 × 6.8 ± 0.5 µm, n = 50); fusiform conidia 7.8–12.7(–13.6) × 5.4–8.02 µm, 95% confidence limits = 10.01–10.7 × 6.3–6.7 µm, (x̄ ± SD = 10.4 ± 1.2 × 6.5 ± 0.6 µm, n = 50); oblong conidia 9.02–15.05(–17.3) × 6.9 – 9.8 µm, 95% confidence limits = 12–12.8 × 8.2–8.7 µm, (x̄ ± SD = 12.4 ± 1.5 × 8.5 ± 0.7 µm, n = 50). Sexual morph not observed. Chlamydospores not observed.

Culture characteristics: Colonies on PDA reaching 21 mm diam after 8 days of incubation at 25 ± 0.5 °C, circular with filiform margin, grey with paler margin, in some area covered by dirty-white, woolly mycelial masses, with age becoming darker, pycnidia scattered on the colony as black dots and aggregated in the centre; reverse blackish brown. Colonies on OA reaching 20 mm diam after 7 days of incubation at 25 ± 0.5 °C, circular with filiform margin, floccose, creamy brown with paler margin, in some area covered by white, woolly mycelial masses; reverse dark brown.

Note:The closely related species to Neocamarosporium suaedae are N.chersinae , N.chichastianum , N.halimiones , N. halocnemi , and N. persepolisi ( Fig. 1 ). These species shared 97.7 % sequence identity in the ITS region (428 bp) attributed to 9 SNPs and 1 bp insertion/deletion. A nucleotide comparison of two new species, N. halocnemi and N. suaedae revealed a difference of 1.4% (6/428 bp) in the ITS region and 1.7% (4/236 bp) in tub2. The tub2 and tef1 sequences of other above species are not available to be included in the nucleotide comparison. Some pycnidia in N. halocnemi have 1–2 short necks similar to those of N. chichastianum , but none of other above species has yet been observed to form a distinct neck ( Crous et al., 2014b; Papizadeh et al., 2017; Crous and Groenewald, 2017; Goncalves et al., 2019). Neocamarosporium halimiones was reported to produce only aseptate, globose conidia ( Goncalves et al. 2019). In addition, N. halocnemi differs from N. suaedae by longer ellipsoid and oblong conidia ( Figs. 2 and 3 , ellipsoid conidia: 11 ± 1.7 × 6.8 ± 0.5 µm vs 9.3 ± 1.3 × 6.9 ± 0.5 µm, oblong conidia: 12.4 ± 1.5 × 8.5 ± 0.7 µm vs 11.1 ± 1.09 × 8.6 ± 0.5 µm).

Figures

FIGURE 1. Phylogenetic tree constructed from a maximum likelihood analysis based on the combined ITS, LSU, tef1α and tub2 sequences of Neocamarosporium strains. The tree was rooted to Stemphylium eturmiunum (CPC 38613). Bootstrap values obtained in maximum likelihood (MLBS) and maximum parsimony (MPBS) analyses ≥ 50% and Bayesian posterior probability values (BYPP) ≥ 0.5 are shown at the nodes, respectively.

FIGURE 2. Neocamarosporium halocnemi (IRAN 5255C). a–b. 8-days colony on PDA in top and reverse sides, c–d. Colony on OA after 8 days, respectively, e–f. Pycnidia. g. Section of pycnidia. h. Pycnidial wall and conidiogenous cells (arrows). i. Conidia. Scale bars: f–g = 70 μm, h–i = 20 μm.

FIGURE 3. Neocamarosporium suaedae (IRAN 4955C). a–b. 8-days colony on PDA in top and reverse sides, c–d. Colony on OA after 8 days, respectively, e–f. Pycnidia. g. Section of pycnidia. h. Pycnidial wall and conidiogenous cells (arrows). i. Conidia. Scale bars: f: 70 μm, g–i = 20 μm, h: 7 μm.