Striaticonidium kfriense Rajeshk., O.P. Sruthi, S. K. Ashtamoorthy & K. V. Sankaran, 2024

Rajeshkumar, Kunhiraman C., Paraparath, Sruthi O., Ashtamoorthy, Sreejith K., Robi, Aloor J., Gautam, Ajay Kumar, Verma, Rajnish Kumar, Jeewon, Rajesh, Ansil, Parayelil A., Karunarathna, Samantha C. & Kavileveettil, Sankaran, 2024, Morpho-molecular systematics of Striaticonidium kfriense (Stachybotryaceae), a new synnematous species from the Western Ghats, India, Phytotaxa 675 (3), pp. 233-246 : 238-239

Striaticonidium kfriense Rajeshk., O.P. Sruthi, S. K. Ashtamoorthy & K. V. Sankaran sp. nov. (Figures 3,4)

Index Fungorum number: IF 902552

Etymology:— The specific epithet kfriense , named after the Kerala Forest Research Institute (KFRI), Kerala, on the occasion of the golden jubilee celebration of the Institution and in recognition of contribution of the institute to the Indian mycology, tropical biodiversity inventory and conservation.

Holotype:— INDIA. Kerala, Karadichola, Vazhachal Forest Division, 10.1739°N, 76.48006°E, on a decaying leaf of Ochlandra travancorica , 23 October 2023, OP Sruthi and KC Rajeshkumar, holotype — AMH 10769 , ex-type culture NFCCI 5854 .

Diagnosis: The synnemata of Striaticonidium kfriense are longer and wider (144–515 × 22–97 µm) compared to the morphologically similar S. synnematum (50–85 × 35–85 μm). The conidiogenous cells were slightly larger and with verrucose apex in S. kfriense (17–36 × 1.5–2 μm) in both in vitro and in vivo conditions than S. synnematum (18–30 × 1–2 μm in vivo and 5–10 × 1–2 μm in vitro). Likewise, conidia were larger and with a prominent truncated base in vitro in S. kfriense (6–12 × 2–4 μm) compared to S. synnematum (7–8 × 2–3 μm).

Saprobic on decaying leaf of Ochlandra travancorica . Sexual morph:Undetermined.Asexual morph: Conidiomata synnematous, solitary, 144–515 × 22–97 µm (x̄ = 337 × 19.8 µm, n = 17); synnemata head 43–97 × 57–115 µm, cylindrical, broadened towards apex, unbranched, consisting of bundles of parallel, longitudinal, closely compacted septate hyphae, terminating in whorls of conidiogenous cells enclosed by marginal thick-walled hyphae in a spirally twisted manner. Marginal hyphae 2.2–2.8 µm wide (x̄ = 2.5 µm, n = 30), branched or unbranched, sinuous, hyaline to olivaceous green, verrucose with a curved blunt apex. Stroma well-developed of textura globulosa and textura angularis. Conidiophores terminating in whorls of 2–4 conidiogenous cells. Conidiogenous cells phialidic, cylindrical to subcylindrical, hyaline, smooth or slightly verrucose towards the apex, 17–36 × 1.5–2 μm (x̄ = 25 × 1.9 µm, n = 30), in vivo with conspicuous collarettes and periclinal thickenings. Conidia aseptate, longitudinally striate, hyaline to olivaceous green, fusiform to ellipsoidal, 6–12 × 2–4 μm (x̄ = 8.5 × 3 μm), with a distinct hilum, truncated base is more prominent in conidia formed in vitro.

Culture characteristics: —Colonies on MEA at 25 ± 2 ºC after 7 d fast growing, 28–32 mm diam., initially white (1 A 1), when mature colonies are light grey (1 C 1) to greenish grey (1 B 2) when mature, reverse yellowish white (4 A 2) to white (3 A 1). Margin regular, brownish grey to grey (6D2 to 6 E 1), slightly umbonate at center, greenish grey (1 B 2). Floccose colony with diurnal pattern. Sporulating on media and forming synnemata on the surface of colonies, covered by slimy herbage to olivaceous green conidial masses.

Notes: Phylogenetic analyses delineated S. kfriense as a new lineage sister to S. synnematum with a statistical support of ML-BS = 67% and PP = 0.95, respectively. In addition, PHI of 0.99, indicates no significant genetic recombination between S. kfriense and its allied taxa.

A synopsis of the five species reported under Striaticonidium is shown in Table 2.